Готові списки джерел за темами / Graphene - Photocatalysis

Добірка наукової літератури з теми "Graphene - Photocatalysis"

Автор: Grafiati
Опубліковано: 7 вересня 2023

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Зміст

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Graphene - Photocatalysis".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Graphene - Photocatalysis"

1

Prakash, Jai. "Mechanistic Insights into Graphene Oxide Driven Photocatalysis as Co-Catalyst and Sole Catalyst in Degradation of Organic Dye Pollutants." Photochem 2, no. 3 (August 17, 2022): 651–71. http://dx.doi.org/10.3390/photochem2030043.

Повний текст джерела
Анотація:
Photocatalysis is a promising route to utilize sunlight, which has been potentially used to solve energy as well as environmental problems with an emphasis on fundamental understanding and technological applications in society. Semiconductors are excellent photocatalysts but often show less efficient activities due to the fast recombination of photogenerated charge carriers and very slow kinetics of surface photochemical reactions. However, recent advancements show promising strategies to improve their photocatalytic activities, including surface modifications using suitable co-catalysts and the development of novel efficient photocatalysts. Graphene oxide (GO) is one of such nanomaterials which shows multifarious roles in photocatalysis with a great potential to act as an independent solar-driven sole photocatalyst. In this minireview, the photochemistry of GO has been discussed in view of its multifarious roles/mechanisms in improving the photocatalytic activity of metal oxide semiconductors, plasmonic nanomaterials, and also their nanocomposites. In addition, recent advancements and applications of such GO-based photocatalysts in photocatalytic degradation of organic dye pollutants, including engineering of GO as the sole photocatalyst, have been discussed. Furthermore, the challenges and future prospects for the development of GO-based photocatalysts are discussed.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Chen, De Qiang, Yang Li та Yi Qun Chen. "Preparation of Graphene and γ-Fe2O3 Doped Titanium Dioxide and its Photocatalytic Properties". Applied Mechanics and Materials 295-298 (лютий 2013): 447–51. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.447.

Повний текст джерела
Анотація:
In this paper graphene is used to improve absorption rate of nano-titanium dioxide under visible light, meanwhile titanium dioxide is doped with superparamagnetism nano-powder of γ-Fe2O3 to modify the recovery of the photocatalyst. Gradually the increasing content of grapheme promotes the removal efficiency and correspondingly. Excitation condition is reduced and the photocatalysis property under visible light is improved and recycle rate of the titanium dioxide is effective promoted after the dispose. The effect of photocatalytic degradation of methylene blue is used to evaluate the photocatalytic activity. The methylene blue degradation rate raised from 53.4% to 85.9% with the increasing graphene load from 5% to 20% under visible light. The degradation efficiency of methylene blue decreased to 15% without the graphene load. The recovery rate of the photocatalyst can achieve 95% above. Graphene oxide works as the electron acceptor and photosensitizer to efficiently enhance the dye photodecomposition.
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Nasir, Amara, Sadia Khalid, Tariq Yasin, and Anca Mazare. "A Review on the Progress and Future of TiO2/Graphene Photocatalysts." Energies 15, no. 17 (August 27, 2022): 6248. http://dx.doi.org/10.3390/en15176248.

Повний текст джерела
Анотація:
TiO2 is seen as a low cost, well-known photocatalyst; nevertheless, its sluggish charge kinetics does limit its applications. To overcome this aspect, one of the recent approaches is the use of its composites with graphene to enhance its photoactivity. Graphene-based materials (nanosheets, quantum dots, etc.) allow for attachment with TiO2 nanostructures, resulting in synergistic properties and thus increasing the functionality of the resulting composite. The current review aims to present the marked progress recently achieved in the use of TiO2/graphene composites in the field of photocatalysis. In this respect, we highlight the progress and insights in TiO2 and graphene composites in photocatalysis, including the basic mechanism of photocatalysis, the possible design strategies of the composites and an overview of how to characterize the graphene in the mixed composites. The use of composites in photocatalysis has also been reviewed, in which the recent literature has opened up more questions related to the reliability, potential, repeatability and connection of photocatalytic mechanisms with the resulting composites. TiO2/graphene-based composites can be a green light in the future of photocatalysis, targeting pollution remediation, energy generation, etc.
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Sánchez, Luis A., Brian E. Huayta, Pierre G. Ramos, and Juan M. Rodriguez. "Enhanced Photocatalytic Activity of ZnO Nanorods/(Graphene Oxide, Reduced Graphene Oxide) for Degradation of Methyl Orange Dye." Journal of Physics: Conference Series 2172, no. 1 (February 1, 2022): 012013. http://dx.doi.org/10.1088/1742-6596/2172/1/012013.

Повний текст джерела
Анотація:
Abstract ZnO has been well-known as a significant photocatalyst material due to its high surface area, efficient charge transport, and superior photosensitivity. Even though photocatalysis using bare ZnO NRs is useful in pollutant remediation, two main drawbacks scale down their performance as photocatalysts. First, ZnO NRs absorb mainly the UV light, which compromises a small portion of the solar spectrum, and second, the high recombination rate in the ZnO NRs prevents the path of electron-hole outward and then reduces the photocatalysis efficiency. In this work, ZnO-NRs, ZnO-NRs/Graphene Oxide (GO), and ZnO-NRs/Reduced Graphene Oxide (rGO) array composites were vertically grown on conductive glass substrates of SnO2:F (FTO). The films were synthesized by hydrothermal method using ZnO seed layers deposited by spray pyrolysis technique. The nanosheets of GO and rGO were anchored onto the surface of the as-prepared ZnO-NRs by using the spray deposition technique (SDT). The photocatalytic activity of these materials was studied by analyzing the degradation of methylene orange (MO) in an aqueous solution under ultraviolet light, and we found that the decoration of ZnO-NRs with nanosheets of GO and rGO resulted in a significant enhancement of the photocatalytic degradation efficiency, where ZnO-NRs/rGO are more efficient than ZnO-NRs/GO and the latter better than pure ZnO-NRs.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Albero, Josep, Diego Mateo, and Hermenegildo García. "Graphene-Based Materials as Efficient Photocatalysts for Water Splitting." Molecules 24, no. 5 (March 5, 2019): 906. http://dx.doi.org/10.3390/molecules24050906.

Повний текст джерела
Анотація:
Photocatalysis has been proposed as one of the most promising approaches for solar fuel production. Among the photocatalysts studied for water splitting, graphene and related materials have recently emerged as attractive candidates due to their striking properties and sustainable production when obtained from biomass wastes. In most of the cases reported so far, graphene has been typically used as additive to enhance its photocatalytic activity of semiconductor materials as consequence of the improved charge separation and visible light harvesting. However, graphene-based materials have demonstrated also intrinsic photocatalytic activity towards solar fuels production, and more specifically for water splitting. The photocatalytic activity of graphene derives from defects generated during synthesis or their introduction through post-synthetic treatments. In this short review, we aim to summarize the most representative examples of graphene based photocatalysts and the different approaches carried out in order to improve the photocatalytic activity towards water splitting. It will be presented that the introduction of defects in the graphenic lattice as well as the incorporation of small amounts of metal or metal oxide nanoparticles on the graphene surface improve the photocatalytic activity of graphene. What is more, a simple one-step preparation method has demonstrated to provide crystal orientation to the nanoparticles strongly grafted on graphene resulting in remarkable photocatalytic properties. These two features, crystal orientation and strong grafting, have been identified as a general methodology to further enhance the photocatalytic activity in graphenebased materials for water splitting. Finally, future prospects in this filed will be also commented.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Hong, Xiaodong, Xu Wang, Yang Li, Jiawei Fu, and Bing Liang. "Progress in Graphene/Metal Oxide Composite Photocatalysts for Degradation of Organic Pollutants." Catalysts 10, no. 8 (August 11, 2020): 921. http://dx.doi.org/10.3390/catal10080921.

Повний текст джерела
Анотація:
The sewage discharge of industrial wastewater seriously pollutes the water source and rivers, which is very harmful to the health of humans and wildlife. Among those methods for treating wastewater, photocatalysis is a sustainable and environmental-friendly technique for removing the organic pollutants with no secondary pollution. As a popular photocatalyst, graphene/metal oxide nanocomposites have been widely reported in the photocatalysis field. In this review, the recent progress of graphene/metal oxide composites including binary and ternary composites is summarized in detail. The synthesis, microstructure design, and application performance of graphene/TiO2, graphene/ZnO, graphene/SnO2, graphene/WO3, graphene/Fe2O3, and graphene/Cu2O composites are introduced firstly. Then, the synthesis, the selection of components, and the performance of various ternary composites are summarized specifically, including graphene/TiO2-, graphene/ZnO-, graphene/SnO2-, graphene/Cu2O-, graphene/FexOy-, and graphene/Bi-containing ternary composites. At last, the possible research directions of graphene/metal oxide nanocomposites are put forward. The main purpose is to provide a theoretical guidance for designing high-performance graphene/metal oxide photocatalysts for wastewater treatment.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Johar, Muhammad Ali, Rana Arslan Afzal, Abdulrahman Ali Alazba, and Umair Manzoor. "Photocatalysis and Bandgap Engineering Using ZnO Nanocomposites." Advances in Materials Science and Engineering 2015 (2015): 1–22. http://dx.doi.org/10.1155/2015/934587.

Повний текст джерела
Анотація:
Nanocomposites have a great potential to work as efficient, multifunctional materials for energy conversion and photoelectrochemical reactions. Nanocomposites may reveal more improved photocatalysis by implying the improvements of their electronic and structural properties than pure photocatalyst. This paper presents the recent work carried out on photoelectrochemical reactions using the composite materials of ZnO with CdS, ZnO with SnO2, ZnO with TiO2, ZnO with Ag2S, and ZnO with graphene and graphene oxide. The photocatalytic efficiency mainly depends upon the light harvesting span of a material, lifetime of photogenerated electron-hole pair, and reactive sites available in the photocatalyst. We reviewed the UV-Vis absorption spectrum of nanocomposite and photodegradation reported by the same material and how photodegradation depends upon the factors described above. Finally the improvement in the absorption band edge of nanocomposite material is discussed.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Cai, Tingwei, Ying Ding, and Lihui Xu. "Synthesis of flower-like CuS/graphene aerogels for dye wastewater treatment." Functional Materials Letters 12, no. 02 (April 2019): 1950002. http://dx.doi.org/10.1142/s1793604719500024.

Повний текст джерела
Анотація:
A novel visible-light flower-like CuS/graphene aerogels (CuS/GAs) photocatalyst has been synthesized via two-step solvothermal method. The CuS/GAs show outstanding synergies of adsorption and photocatalysis for anionic–cationic dyes degradation, which is attributed to unique network structure and excellent photoelectric properties of GAs. The high degradation ratio of Methyl orange and Methylene blue by synergy are 92% and 99.36%, which are about 4.1 and 3.2 times of that for pure CuS. The flower-like CuS/graphene aerogels resolve the low adsorption saturation problem of GAs and improve the photocatalytic performance of CuS, indicating CuS/GAs could be a promising photocatalyst for wastewater treatment.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Yang, Zanhe, Siqi Zhou, Xiangyu Feng, Nannan Wang, Oluwafunmilola Ola, and Yanqiu Zhu. "Recent Progress in Multifunctional Graphene-Based Nanocomposites for Photocatalysis and Electrocatalysis Application." Nanomaterials 13, no. 13 (July 7, 2023): 2028. http://dx.doi.org/10.3390/nano13132028.

Повний текст джерела
Анотація:
The global energy shortage and environmental degradation are two major issues of concern in today’s society. The production of renewable energy and the treatment of pollutants are currently the mainstream research directions in the field of photocatalysis. In addition, over the last decade or so, graphene (GR) has been widely used in photocatalysis due to its unique physical and chemical properties, such as its large light-absorption range, high adsorption capacity, large specific surface area, and excellent electronic conductivity. Here, we first introduce the unique properties of graphene, such as its high specific surface area, chemical stability, etc. Then, the basic principles of photocatalytic hydrolysis, pollutant degradation, and the photocatalytic reduction of CO2 are summarized. We then give an overview of the optimization strategies for graphene-based photocatalysis and the latest advances in its application. Finally, we present challenges and perspectives for graphene-based applications in this field in light of recent developments.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Chen, Yanling, and Xue Bai. "A Review on Quantum Dots Modified g-C3N4-Based Photocatalysts with Improved Photocatalytic Activity." Catalysts 10, no. 1 (January 20, 2020): 142. http://dx.doi.org/10.3390/catal10010142.

Повний текст джерела
Анотація:
In the 21st century, the development of sustainable energy and advanced technologies to cope with energy shortages and environmental pollution has become vital. Semiconductor photocatalysis is a promising technology that can directly convert solar energy to chemical energy and is extensively used for its environmentally-friendly properties. In the field of photocatalysis, graphitic carbon nitride (g-C3N4) has obtained increasing interest due to its unique physicochemical properties. Therefore, numerous researchers have attempted to integrate quantum dots (QDs) with g-C3N4 to optimize the photocatalytic activity. In this review, recent progress in combining g-C3N4 with QDs for synthesizing new photocatalysts was introduced. The methods of QDs/g-C3N4-based photocatalysts synthesis are summarized. Recent studies assessing the application of photocatalytic performance and mechanism of modification of g-C3N4 with carbon quantum dots (CQDs), graphene quantum dots (GQDs), and g-C3N4 QDs are herein discussed. Lastly, challenges and future perspectives of QDs modified g-C3N4-based photocatalysts in photocatalytic applications are discussed. We hope that this review will provide a valuable overview and insight for the promotion of applications of QDs modified g-C3N4 based-photocatalysts.
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Дисертації з теми "Graphene - Photocatalysis"

1

Chalangar, Ebrahim. "Graphene-based nanocomposites for electronics and photocatalysis." Licentiate thesis, Linköpings universitet, Fysik, elektroteknik och matematik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-157095.

Повний текст джерела
Анотація:
The development of future electronics depends on the availability of suitable functional materials. Printed electronics, for example, relies on access to highly conductive, inexpensive and printable materials, while strong light absorption and low carrier recombination rates are demanded in photocatalysis industry. Despite all efforts to develop new materials, it still remains a challenge to have all the desirable aspects in a single material. One possible route towards novel functional materials, with improved and unprecedented physical properties, is to form composites of different selected materials. In this work, we report on hydrothermal growth and characterization of graphene/zinc oxide (GR/ZnO) nanocomposites, suited for electronics and photocatalysis application. For conductive purposes, highly Al-doped ZnO nanorods grown on graphene nanoplates (GNPs) prevent the GNPs from agglomerating and promote conductive paths between the GNPs. The effect of the ZnO nanorod morphology and GR dispersity on the nanocomposite conductivity and GR/ZnO nanorod bonding strength were investigated by conductivity measurements and optical spectroscopy. The inspected samples show that growth in high pH solutions promotes a better graphene dispersity, higher doping and enhanced bonding between the GNPs and the ZnO nanorods. Growth in low pH solutions yield samples characterized by a higher conductivity and a reduced number of surface defects. In addition, different GR/ZnO nanocomposites, decorated with plasmonic silver iodide (AgI) nanoparticles, were synthesized and analyzed for solar-driven photocatalysis. The addition of Ag/AgI generates a strong surface plasmon resonance effect involving metallic Ag0, which redshifts the optical absorption maximum into the visible light region enhancing the photocatalytic performance under solar irradiation. A wide range of characterization techniques including, electron microscopy, photoelectron spectroscopy and x-ray diffraction confirm a successful formation of photocatalysts. Our findings show that the novel proposed GR-based nanocomposites can lead to further development of efficient photocatalyst materials with applications in removal of organic pollutants, or for fabrication of large volumes of inexpensive porous conjugated GR-semiconductor composites.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Sass, Danielle. "Nano silver-Iron-reduced graphene oxide modified titanium dioxide photocatalyst for the remediation of Organic dye in water systems." University of the Western Cape, 2018. http://hdl.handle.net/11394/6274.

Повний текст джерела
Анотація:
Magister Scientiae - MSc (Chemistry)
Drinking water with high concentrations of inorganic and organic contaminants can cause adverse health defects. Specifically methyl orange dye is an organic water contaminant that has been known (along with others like methyl blue etc.) to have an increase in our water systems over the past few years due to increasing demand in industrial processes. It is therefore of utmost importance to remediate organic contaminants and ultimately enable prevention. The contaminants can be removed by photocatalysis. Anatase TiO2 is known for its photocatalytic degradation of environmental pollutants and photoelectro-chemical conversion of solar energy. However its application is limited since it is a wide band gap semiconductor, (Eg = 3.2 eV). The following study deals with the enhancement of the photocatalytic properties of TiO2 for remediation of organic water contaminants. The study was carried out to produce the two nanocomposites AgFe-TiO2 and AgFe-TiO2-rGO photocatalyst which purpose is to be cheap and easy to apply, with improved (fast and effective) photocatalytic degradation of methyl orange. The main objective was to decrease the band gap and to introduce intra-band gap states to absorb visible light. Modification of the TiO2 with small bandgap semiconductor, graphene and Ag- Fe nanoalloy reduced the bandgap energy for visible light absorption and photocatalytic degradation of methyl orange dye. The two composites were synthesised using sonication and chemical synthesis methods. A photocatalytic study (degradation of methyl orange dye) was carried out using a system incorporating an UV lamp source to determine the degradation of methyl orange catalysed by the synthesised photocatalysts AgFe-TiO2-rGO and AgFe-TiO2 along with UV-vis Spectroscopy. Morphological studies were carried out using HRSEM and HRTEM which determined the spherical agglomerated nature of AgFe-TiO2 and the sheet-like nature of AgFe-TiO2-rGO containing spherical agglomerants but that also contained pockets formed by the sheets of the rGO. XRD served as confirmation of the phase of TiO2 in both composites to be anatase. Analysis confirmed the formation and elemental determination of both composites. It was observed that the Band gap of TiO2 degussa decreased from 2.94 eV to 2.77 eV in the composite AgFe-TiO2. The photocatalytic reactivity of AgFe- TiO2 was an improvement from TiO2 and AgFe-TiO2-rGO based on the photocatalytic study. Therefore concluding that AgFe-TiO2 was the best catalyst to convert the dye (Orange II) into free radicals and ultimately remove the contaminant from the water compared to AgFe-TiO2-rGO.
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Hamandi, Marwa. "Élaboration et caractérisation d’oxydes de Titane de Morphologie Contrôlée : application à la Photodégradation de Polluants Organiques." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1077/document.

Повний текст джерела
Анотація:
Ce travail se résume en deux objectifs principaux. Le premier concerne l'élaboration de matériaux nanohybrides de dioxyde de titane (sous forme sphérique ou tubulaire) décoré par des allotropes de carbone (fullerène fonctionnalisé ou graphène). Le deuxième objectif consiste à l'évaluation de ces différents nanomatériaux dans la photodégradation de l'acide formique (AF) sous irradiation UV. Un effet bénéfique des allotropes de carbone sur l'activité photocatalytique des nanohybrides a été observé suite à l'augmentation de la durée de vie des paires électron-trou photogénérées. Dans un premier temps, la méthode d'élaboration et la teneur en fullerène fonctionnalisé ont été optimisées conduisant ainsi à l'élaboration de nanomatériaux révélant des propriétés photocatalytiques améliorées par rapport au TiO2 nanotube seul. Une corrélation entre les propriétés texturales, les propriétés photoélectriques et la constante de vitesse de dégradation de l'AF a été établie afin d'élucider les causes de l'amélioration de l'activité photocatalytique. Dans un second temps, une étude détaillée portant sur l'élaboration d'une nouvelle génération de nanocomposites combinant nanotubes de TiO2 et oxyde de graphène (OG) a été menée. Le degré de réduction de l'oxyde de graphène influence fortement l'activité photocatalytique. Ainsi, l'addition d'OG ou OG réduit aux nanotubes de TiO2 influence positivement les performances intrinsèques en photodégradation de l'acide formique en facilitant le transfert de photoélectrons de la bande de conduction du TiO2 vers l'oxyde de graphène. Finalement, l'étude des matériaux composites combinant l'oxyde de graphène et diverses compositions anatase/rutile a permis de mettre en évidence une synergie entre le OG et les deux phases TiO2
Two main objectives were achieved in the present work. The first objective concerns the elaboration of nanohybrid materials formed by combining titanium dioxide (in spherical or tubular form) with carbon allotropes (functionalized fullerene or graphene). The second objective consists in evaluating these different nanomaterials in the photodegradation of formic acid (FA) under UV irradiation. A beneficial effect of the different carbon allotropes on the photocatalytic activity of the resulting nanohybrids was observed and ascribed to an increased lifetime of photogenerated electron-hole pairs. In a first step, the elaboration method of functionalized fullerenes and their content were optimized leading to the development of nanomaterials showing improved photocatalytic properties compared to TiO2 nanotube alone. Textural properties, photoelectric properties and the FA degradation rate constant were correlated in order to determine the reasons for the photocatalytic activity improvement. In a second step, a detailed study about the development of a new generation of nanocomposites combining TiO2 nanotubes and graphene oxide (GO) was carried out. The degree of reduction of GO strongly influences the photocatalytic activity. Thus, the addition of reduced GO or GO to TiO2 nanotubes improves the intrinsic photodegradation performance of formic acid by facilitating the transfer of photoelectrons from the conduction band of TiO2 to graphene oxide. Finally, composite materials combining graphene oxide and various anatase/rutile compositions were analyzed showing a synergy between GO and the two TiO2 phases
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Tomarchio, Flavia. "Nanomaterials-based inks for flexible electronics, energy and photocatalytic applications." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/275888.

Повний текст джерела
Анотація:
Due to the combination of their electronic, optical and mechanical properties, graphene and other layered materials (GRMs) have great potential for applications such as flexible optoelectronics and energy storage. Given that GRMs can be dispersed in solvents, solution processing is a particularly interesting approach that allows large volume production with tailored properties according to the targeted applications. \par In this dissertation I investigate liquid phase exfoliation and formulation of GRMs-based inks for flexible (opto) electronics, energy and photocatalysis. First I develop a protocol for the characterization of graphene inks, based on the statistical analysis of their Raman spectra. Such a tool is essential because of the scattering of characteristics in liquid-phase exfoliated material. I then report two novel processing techniques. The first consists on the exfoliation of graphene in organic solvents by the means of $\alpha$-functionalized alkanes as stabilising agents, which allows yield by weight ($Y_W$) of $\sim 100\%$. The second is based on exfoliation of graphite by microfluidization, where the material is stabilised in aqueous solution, with concentrations up to 100g/L. Such inks are successfully deposited by blade coating, leading to films of conductivity $\sim$ 2$\cdot$10$^4$ S/m at 25$\mu$m. I then investigate the use of graphene inks in optoelectronics and energy applications: First, I investigate inkjet printed graphene as hole injection layer (HTL). The cells with graphene HTL show high long-term stability, retaining 85$\%$ of the initial fill factor after 900 hrs in damp heat conditions. I then demonstrate flexible displays with graphene-SWNTs as pixel electrode. A 4x4 inch$^2$ demonstrator is realised integrating the ink into 12,700 pixels. I investigate graphene/MoO$_3$ electrode for supercapacitors with a specific capacitance of 342 F/cm$^3$. The electrode shows high cyclic stability, preserving $\sim$96$\%$ of the initial capacitance after 10,000 cycles. I finally report the production of TiO$_2$/exfoliated graphite as efficient photocatalytic composite able to degrade $\sim$100$\%$ more model pollutant with respect to TiO$_2$.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Sass, Danielle Thandi. "Nano silver-iron-reduced graphene oxide modified titanium dioxide photocatalyst for the remediation of organic dye in water systems." University of the Western Cape, 2018. http://hdl.handle.net/11394/6410.

Повний текст джерела
Анотація:
Magister Scientiae - MSc (Chemistry)
Drinking water with high concentrations of inorganic and organic contaminants can cause adverse health defects. Specifically methyl orange dye is an organic water contaminant that has been known (along with others like methyl blue etc.) to have an increase in our water systems over the past few years due to increasing demand in industrial processes. It is therefore of utmost importance to remediate organic contaminants and ultimately enable prevention. The contaminants can be removed by photocatalysis. Anatase TiO2 is known for its photocatalytic degradation of environmental pollutants and photoelectro-chemical conversion of solar energy. However its application is limited since it is a wide band gap semiconductor, (Eg = 3.2 eV). The following study deals with the enhancement of the photocatalytic properties of TiO2 for remediation of organic water contaminants.
2021-12-31
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Papa, Letizia. "Synthesis of hybrid nanosheets of graphene oxide, titania and gold and palladium nanoparticles for catalytic applications." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-19062017-083751/.

Повний текст джерела
Анотація:
Nanocatalysis has emerged in the last decades as an interface between homogeneous and heterogeneous catalysis, offering simple solutions to problems that conventional materials have not been able to solve. In fact, nanocatalyst design permits to obtain structures with high superficial area, reactivity and stability, and at the same time presenting good selectivity and facility of separation from reaction mixtures. In this work, we prepared hybrid structures comprising gold, palladium and silver nanoparticles (Au, Pd and Ag NPs), titanate nanosheets (TixO2), graphene oxide (GO), and partially reduced graphene oxide (prGO). We focused on bi- and tri-components hybrids, namely TixO2, M/(pr)GO and M/TixO2/(pr)GO (M = Au, Pd or Ag) and developed facile, versatile and environment-friendly preparation methods with an emphasis on control over physicochemical features such as size, shape and composition. In order to exploit the catalytic applications, we employed the reduction of 4-nitrophenol as a model reaction, followed by visible-light assisted oxidation of p-aminothiophenol (PATP). With these tests, we unraveled metal-support interactions and cooperative effects that render hybrid structures superior to their individual counterparts.
A nanocatálise surgiu nas últimas décadas como uma interface entre catálise homogênea e heterogênea, oferecendo soluções simples a problemas que os materiais convencionais não conseguiram resolver. De fato, o design de nanocatalisadores permite obter estruturas com grande área superficial, reatividade e estabilidade, e ao mesmo tempo apresentando boa seletividade e facilidade de separação de misturas reacionais. Neste trabalho apresentamos a preparação de estruturas híbridas compostas por nanopartículas de ouro, paládio e prata (Au, Pd e Ag NPs), nanofolhas de titanato (TixO2), óxido de grafeno (GO) e óxido de grafeno parcialmente reduzido (prGO). Focamos em híbridos do tipo M/TixO2, M/(pr)GO e M/TixO2/(pr)GO (M = Au, Pd ou Ag) e desenvolvemos métodos de preparação simples, versáteis e ambientalmente amigáveis, com ênfase no controle sobre tamanho, forma e composição. Para explorar as potencialidades catalíticas utilizamos a redução do 4-nitrofenol como reação modelo, e em seguida a oxidação assistida por luz do p-aminotiofenol (PATP). Com esses testes, investigamos interações metal-suporte e efeitos cooperativos que tornam as estruturas hibridas superiores a cada um dos materiais que as compõem.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Moussa, Hatem. "Influence de l’association de quantum dots ZnO avec des ions Cu²+ sur leur (photo)toxicité. Nouveaux matériaux ZnO/rGO pour la photocatalyse solaire." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0036/document.

Повний текст джерела
Анотація:
Ces dernières années, les énormes progrès réalisés en nanotechnologie ainsi qu’en science des matériaux ont conduit à la préparation de nombreuses nouvelles nanoparticules sans réellement connaître l’ensemble des propriétés associées à leurs dimensions. La première partie de notre travail vise à évaluer les risques et les problèmes associés aux nanomatériaux, en termes de toxicité, en utilisant des nanoparticules de ZnO. Nous avons tout d’abord étudié la capacité de ces nanoparticules à générer des espèces réactives d’oxygènes (EROs) sous irradiation UV en utilisant trois types des quantum dots (QDs) comme modèles, ZnO, ZnO dopé avec des ions Cu2+ et ZnO avec des ions Cu2+ adsorbés à sa surface. Les trois types des QDs ont montré une forte capacité à générer des EROs mais ceux modifiés par les ions Cu2+ en périphérie sont les plus producteurs. Ces QDs inhibent également le plus fortement la croissance de la bactérie E. coli. La toxicité n’est cependant pas dépendante des EROs photo-produits ni du zinc (+2) libéré par les QDs et montre qu’un mécanisme plus complexe doit être considéré. Dans une second partie, nous avons tenté d’améliorer l’activité photocatalytique de nanobâtonnets de ZnO en les associant à de l’oxyde de graphène réduit (rGO). Des nanocomposites ZnO/rGO ont été préparés par voie solvothermale et utilisés pour la phototodégradation du colorant Orange II comme modèle de polluant. Les résultats obtenus montrent que le photocatalyseur ZnO/rGO est très efficace sous irradiation solaire ou visible et qu’il est peu sensible à des variations de pH ou à la présence de perturbateurs dans le milieu. Finalement, le photocatalyseur est très stable et peut être réutilisé plus de dix fois sans perte notable d’activité
In recent years, tremendous advances in nanotechnology and materials science have led to the synthesis of many new nanoparticles without really knowing all the properties associated with their dimensions. The first part of our work aims to evaluate the risks and problems associated with nanomaterials, in terms of toxicity, using ZnO nanoparticles. We first studied the ability of these nanoparticles to produce reactive oxygen species (ROS) under UV irradiation using three ZnO-based quantum dots (QDs) as models, ZnO, ZnO doped with Cu2+ ions and ZnO with chimisorbed Cu2+ ions at their periphery. The three QDs have a strong capacity of generating ROS but those modified with Cu2+ at their surface were found the be the highest producers. These dots were also found to inhibit more markedly the growth of the E. coli bacteria. The toxicity does neither depend on the amount of photo-generated ROS nor on the amount of Zn(+2) leaked by the QDs, thus indicating that a more complex mechanism should be considered. In a second part, we tried to improve the photocatalytic efficiency of ZnO nanorods by associating these nanomaterials with reduced graphene oxide (rGO). ZnO/rGO composites were prepared by a solvothermal method and applied for the photodegradation of Orange II used as model pollutant. Results obtained demonstrate that the ZnO/rGO photocatalyst is highly efficient under solar and under visible light irradiation and weakly sensitive to pH changes and to the presence of perturbators in the reaction medium. Finally, the photocatalyst is stable and can be reused up to ten times without significant loss of catalytic activity
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Nasr, Maryline. "Elaboration of oxides membranes by electrospinning for photocatalytic applications." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT210/document.

Повний текст джерела
Анотація:
De nos jours, les produits chimiques toxiques industriels ne sont pas toujours traités proprement, et leurs contaminants peuvent directement affecter la sécurité de l'eau potable. La photocatalyse, «une technologie verte» est une approche efficace et économique qui joue un rôle important dans la conversion de l'énergie solaire et la dégradation des polluants organiques. Ce manuscrit de thèse rapporte sur le développement des matériaux avancés (basés sur TiO2 et ZnO) susceptibles d'exploiter l'énergie solaire renouvelable pour résoudre les problèmes de pollution environnementale. Une partie de ce travail a été consacrée pour l’amélioration de l’activité photocatalytique du TiO2 sous lumière UV et visible. Par conséquent, les nanofibres composites de rGO/TiO2, BN/TiO2 et BN-Ag/TiO2 ont été élaborées en utilisant la technique d'électrofilage (electrospinning). La deuxième partie porte sur le ZnO, ainsi que les nanotubes multi co-centriques de ZnO/ZnAl2O4 et les nanotubes de ZnO dopés Al2O3 qui ont été synthétisés en combinant les deux techniques : dépôt de couche atomique (ALD) et electrospinning. Les propriétés morphologiques, structurelles et optiques de toutes les nanostructures synthétisées ont été étudiées par différentes techniques de caractérisations. Les résultats ont montré que les propriétés chimiques et physiques ont un effet très important sur les propriétés photocatalytiques des matériaux synthétisés. En outre, il a été constaté que l'effet de dopage conduit à une séparation de charge efficace dans le photocatalyseur, ce qui rend l’activité photocatalytique plus efficace. De plus, le méthyle orange et le bleu de méthylène ont été utilisés comme modèle de référence. Une amélioration significative et une stabilité à long terme de l’activité photocatalytique ont été observées avec les matériaux dopés comparés aux matériaux non-dopés sous lumière UV et visible. Des tests antibactériens contre Escherichia coli ont été également effectués; les résultats indiquent que BN-Ag/TiO2 présente à la fois des propriétés photocatalytiques intéressantes pour la dégradation des composés organiques et pour l'élimination des bactéries
Nowadays, industrial toxic chemicals are still not properly treated and these contaminants may directly impact the safety of drinking water. Photocatalysis “a green technology” is an effective and economical approach and plays an important role in solar energy conversion and degradation of organic pollutants. This thesis manuscript reports on developing advanced materials (based on TiO2 and ZnO) being capable of exploiting renewable solar energy for solving the environmental pollution problems. A part of this work was dedicated to improve the UV and visible light TiO2 photoresponse. Therefore, rGO/TiO2, BN/TiO2 and BN-Ag/TiO2 composties nanofibers were successfully elaborated using the electrospinning technique. The second part focused on ZnO. Novel structures of ZnO/ZnAl2O4 multi co-centric nanotubes and Al2O3 doped ZnO nanotubes were designed by combining the two techniques of atomic layer deposition (ALD) and electrospinning. The morphological, structural and optical properties of all synthesized nanostructures were investigated by several characterization techniques. The results show that the chemical and physical properties have a high impact on the photocatalytic properties of the synthesized materials. Moreover, it was found that the doping effect lead to a more efficient charge separation in the photocatalyst, which is an advantage for photocatalytic activities. In addition, methyl orange and methylene blue were used as model reference. A significant enhancement and a long-term stability in the photocatalytic activity were observed with the doped materials compared to the non-doped ones under both UV and visible light. Antibacterial tests against Escherichia coli have also been performed; the results indicate that BN-Ag/TiO2 present interesting photocatalytic properties for both organic compound degradation and bacterial removal
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Herring, Natalie. "Formation Mechanisms and Photocatalytic Properties of ZnO-Based Nanomaterials." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/494.

Повний текст джерела
Анотація:
Zinc Oxide (ZnO) is one of the most extensively studied semiconductors because of its unique properties, namely, its wide band gap (3.37 eV) and high excitation binding energy (60 meV). These properties make ZnO a promising material for uses in a broad range of applications including sensors, catalysis and optoelectronic devices. The presented research covers a broad spectrum of these interesting nanomaterials, from their synthesis and characterization to their use as photocatalyts. A new synthetic approach for producing morphology controlled ZnO nanostructures was developed using microwave irradiation (MWI). The rapid decomposition of zinc acetate in the presence of a mixture of oleic acid (OAC) and oleylamine (OAM) results in the formation of hexagonal ZnO nanopyramids and ZnO rods of varying aspect ratios. The factors that influence the morphology of these ZnO nanostructures were investigated. Using ligand exchange, the ZnO nanostructures can be dispersed in aqueous medium, thus allowing their use as photocatalysts for the degradation of malachite green dye in water. Photocatalytic activity is studied as a function of morphology; and, the ZnO nanorods show enhanced photocatalytic activity for the degradation of the dye compared to hexagonal ZnO nanopyramids. After demonstrating the catalytic activity of these ZnO nanostructures, various ways to enhance photocatalytic activity were studied by modification of this MWI method. Photocatalytic activity is enhanced through band gap modulation and the reduction of electron-hole recombination. Several approaches were studied, which included the incorporation of Au nanoparticles, N-doping of ZnO, supporting ZnO nanostructures on reduced graphene oxide (RGO), and supporting N-doped ZnO on N-doped RGO. ZnO-based nanostructures were studied systematically through the entire process from synthesis and characterization to their use as photocatalysis. This allows for a thorough understanding of the parameters that impact these processes and their unique photocatalytic properties.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

He, Jijiang. "Preparation and photocatalysis of graphite carbon nitride based photocatalysts." Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/521.

Повний текст джерела
Анотація:
The connection between ritual and the interior is interrogated through a theoretical framework integrating Van Gennep’s Rites of Passage Theory and Turner’s Theory of Liminality. A multi-faceted methodological framework is developed from the interrogation of the disciplinary edges of multiple methodologies, addressing the experiential, cultural and subjective dimensions of ritual. This new way of exploring the interior demonstrates how knowledge can be acquired from the body’s immersion in unfolding ritual situations, revealing elements of ritual and interior in relation to one another and the generation of new theories on the interior.
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Книги з теми "Graphene - Photocatalysis"

1

Graphene Oxide-Metal Oxide and Other Graphene Oxide-based Composites in Photocatalysis and Electrocatalysis. Elsevier, 2022. http://dx.doi.org/10.1016/c2020-0-01725-1.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Korotcenkov, Ghenadii, Jiaguo Yu, Liuyang Zhang, and Panyong Kuang. Graphene Oxide-Metal Oxide and other Graphene Oxide-Based Composites in Photocatalysis and Electrocatalysis. Elsevier, 2022.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Korotcenkov, Ghenadii, Jiaguo Yu, Liuyang Zhang, and Panyong Kuang. Graphene Oxide-Metal Oxide and Other Graphene Oxide-Based Composites in Photocatalysis and Electrocatalysis. Elsevier, 2022.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Частини книг з теми "Graphene - Photocatalysis"

1

Pastrana-Martínez, Luisa M., Sergio Morales-Torres, José L. Figueiredo, Joaquim L. Faria, and Adrián M. T. Silva. "Graphene Derivatives in Photocatalysis." In Graphene-based Energy Devices, 249–76. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527690312.ch8.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Suresh, R., R. V. Mangalaraja, Héctor D. Mansilla, Paola Santander, and Jorge Yáñez. "Reduced Graphene Oxide-Based Photocatalysis." In Environmental Chemistry for a Sustainable World, 145–66. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-15608-4_6.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Hu, Han, Songcan Wang, and Lianzhou Wang. "CHAPTER 5. Functionalization of Chemically Derived Graphene for Photocatalysis." In Chemically Derived Graphene, 128–54. Cambridge: Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788012829-00128.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Xing, Mingyang, Bocheng Qiu, Xiao Li, and Jinlong Zhang. "TiO2/Graphene Composites with Excellent Performance in Photocatalysis." In Nanostructured Photocatalysts, 23–67. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-26079-2_2.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Zheng, Alvin Lim Teik, and Yoshito Andou. "Hybrid Three-Dimensional (3D) Graphene Architectures for Photocatalysis of Noxious Pollutants." In Green Nanoarchitectonics, 47–72. New York: Jenny Stanford Publishing, 2022. http://dx.doi.org/10.1201/9781003318606-3.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Khalid, N. R., M. Bilal Tahir, A. Majid, E. Ahmed, M. Ahmad, Sadia Khalid, and W. Ahmed. "TiO2-Graphene-Based Composites: Synthesis, Characterization, and Application in Photocatalysis of Organic Pollutants." In Micro and Nanomanufacturing Volume II, 95–122. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-67132-1_5.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Melillo, Arianna, Sergio Navalón, José Raúl Herance, and Hermenegildo García. "Chapter 3. Photocatalysis by Graphenes." In Photocatalysis Using 2D Nanomaterials, 150–69. Cambridge: Royal Society of Chemistry, 2022. http://dx.doi.org/10.1039/9781839164620-00150.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Wang, Wanjun, Donald K. L. Chan, and Jimmy C. Yu. "Graphene-Based Photocatalysts for Energy Applications: Progress and Future Prospects." In Graphene-based Energy Devices, 277–94. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527690312.ch9.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Kuvarega, Alex T., Rengaraj Selvaraj, and Bhekie B. Mamba. "Graphene-Based Photocatalytic Materials: An Overview." In Nanostructured Materials for Environmental Applications, 433–54. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-72076-6_17.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Anku, William W., Ephraim M. Kiarii, Rama Sharma, Girish M. Joshi, Sudheesh K. Shukla, and Penny P. Govender. "Photocatalytic Degradation of Pharmaceuticals Using Graphene Based Materials." In A New Generation Material Graphene: Applications in Water Technology, 187–208. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-75484-0_7.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Graphene - Photocatalysis"

1

Chen, Yen-Shin, Bo-Kai Chao, Tadaaki Nagao, and Chun-Hway Hsueh. "Improvement of Photocatalytic Efficiency by Adding Ag Nanoparticles and Reduced Graphene Oxide to TiO2." In JSAP-OSA Joint Symposia. Washington, D.C.: Optica Publishing Group, 2017. http://dx.doi.org/10.1364/jsap.2017.5p_a410_12.

Повний текст джерела
Анотація:
Titanium dioxide (TiO2) is the commonly used photocatalyst. However, because only a small ultraviolet portion of solar spectrum can excite the electron-hole pairs resulting from the large band gap (3.2 eV) [1] and the recombination rate is high, its efficiency is restrained. To overcome this drawback, we added silver nanoparticles and reduced graphene oxide (RGO) to construct the ternary plasmonic catalyst to improve the catalytic performance of TiO2 nanopowder (P25). We prepared three different geometries of Ag nanostructures including sphere, decahedron and prism because the plasmon resonance properties of Ag could be controlled by the morphology of Ag nanoparticle, which shows characteristic strong localized surface plasmon resonance (LSPR) leading to an increase in light absorption [2]. The incorporated RGO inhibited the charge recombination and enhanced the electron-hole separation. In this study, Ag nanodecahedrons/P25/RGO and Ag nano-prisms/P25/RGO hybrid photocatalysts possessed remarkable photocatalytic activity, which displayed over 8 times higher photocatalytic efficiency than the P25 photocatalyst.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Kim, Chang Hyo, Bo-Hye Kim, and Kap Seung Yang. "IT02. TiO2 nanoparticles loaded on graphene/carbon composite nanofibers by electrospinning for increased photocatalysis." In 2015 2nd International Symposium on Physics and Technology of Sensors (ISPTS). IEEE, 2015. http://dx.doi.org/10.1109/ispts.2015.7220142.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Bockute, Kristina. "Photoluminescence and structural defects of ZnO films deposited by reactive magnetron sputtering with unconventional Ar-O2 gas mixture formation." In SurfCoat Korea and Graphene Korea 2021 International Joint Virtual Conferences. Setcor Conferences and Events, 2021. http://dx.doi.org/10.26799/cp-surfcoat-graphene-korea-2021/1.

Повний текст джерела
Анотація:
ZnO is a well-known traditional industrial material which has high potential to become one of the key components for the next generation of future electronics, LED emitters, visible light photocatalysis and others. In its pristine form ZnO has relatively wide band gap of approximately 3.4 eV, but a lot of emerging applications requires some level of electronic structure engineering and structure optimisation. Studies show that ZnO properties strongly depend on the intrinsic defects type and concentrations. Both characteristics usually are depending on the synthesis method. Accordingly, there is great interest to develop new methods which would allow to obtain ZnO with optimised band gap and other properties. In current, study ZnO films were deposited using reactive magnetron sputtering with unconventional Ar-O2 gas mixture supply control: Ar flow was controlled to maintain total gas pressure at 1x10-2 mbar, whereas O2 flow rate was actively adjusted to maintain the selected intensity of optical zinc emission from the working cathode zone. Applying such ZnO formation method it was possible to stabilise reactive magnetron sputtering process over wide range of conditions. Elemental composition analysis by XPS revealed that despite large variations in Zn emission peak intensity within tested experimental conditions all films had nearly identical Zn:O ratios but at the same time their structural and optical properties differed significantly. The colour of the films varied from highly transparent yellowish-greenish, to intense orange, to opaque black. XRD analysis showed that films consisted of single polycrystalline wurtzite phase with varying orientations. PL spectroscopy analysis revealed that films had a lot of various defects including oxygen and zinc vacancies, interstitials and surface defects. Wide variation of ZnO properties obtained by different reactive sputtering conditions demonstrates the potential of the proposed method to control the formation of various intrinsic defects and to tailor their concentration.
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Liu, Qi, and Hucai Zhang. "Effects of the Graphene Photocatalysis Treatment on Microbial Eukaryotic Community Structure in Lake Xingyun, Southwestern China." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.1602.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Islam, Syed Z., Namal Wanninayake, Allen D. Reed, Doo-Young Kim, and Stephen E. Rankin. "Synergistic effects of graphene quantum dot sensitization and nitrogen doping of ordered mesoporous TiO2 thin films for water splitting photocatalysis (Conference Presentation)." In Solar Hydrogen and Nanotechnology XI, edited by Chung-Li Dong. SPIE, 2016. http://dx.doi.org/10.1117/12.2237971.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Aydın, Kemal Bartu, Levent Aydin, and Fethullah Güneş. "Stochastic Optimization of TiO2-Graphene Nanocomposite by Using Neuro-Regression Approach for Maximum Photocatalytic Degradation Rate." In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.044.

Повний текст джерела
Анотація:
TiO2 is one of the most common materials for photocatalytic applications due to its stability, affordability, and photoactive efficiency. However, it has some drawbacks, such as limited solar radiation response and quick recombination of excitons. Using graphene could be one of the methods to enhance the photocatalytic properties of TiO2. This study intends to optimize the photocatalytic performance of TiO2/Graphene (TiO2/G) nanocomposite by using neuro-regression analysis. In the analysis, the effect of some hydrothermal synthesis parameters, namely, amount of graphene oxide, ethanol/water ratio, and hydrothermal reaction time on the photocatalytic activity of TiO2/G nanocomposite, have been investigated. The parameters were determined from a literature study focused on overcoming the drawbacks of TiO2 by combining it with graphene oxide. Nelder-Mead, Simulated Annealing, Differential Evolution, and Random Search algorithms are used to obtain the optimum synthesis parameters for maximum photocatalytic activity in the optimization process. The results are indicated that all algorithms give the realizable value for design variables and photodegradation rate.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Kanbur, Kürşat, Işıl Birlik, Fatih Sargin, Funda Ak Azem, and Ahmet Türk. "Optimization of Oxidation Time During Graphene Oxide Production." In 7th International Students Science Congress. Izmir International guest Students Association, 2023. http://dx.doi.org/10.52460/issc.2023.045.

Повний текст джерела
Анотація:
Graphene oxide (GO) consists of one or several stacked graphene structures equipped with various functional groups. It has applications in many areas such as biomaterials, energy storage. sensors and photocatalytic degradation thanks to its high surface area, adjustable band gap and dispersibility in various solvents. Although there are various production techniques for GO synthesis, Improved Hummer’s Method stands out with its high efficiency and controllable production parameters. In this method, graphite is oxidized after intercalation with various acids and GO is obtained by exfoliation in the next stages. The effects of production parameters such as oxidation time, oxidant type, oxidant amount, drying processes are generally investigated in Hummer's method. In this study, the effect of oxidation time on GO structure was investigated. In this context, GO was synthesized with various oxidation times by using Modified Hummer's Method. Then, the structural and optical properties of GO were investigated by X-Ray diffraction (XRD), Fourier-Transform infrared spectroscopy (FTIR) and UV-Visible Light spectrophotometer (UV-Vis). The results showed that there is an optimum oxidation time for the oxidation degree of GO structure.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Kanbur, Kürşat, Işıl Birlik, Fatih Sargin, Funda Ak Azem, and Ahmet Türk. "Optimization of Oxidation Time During Graphene Oxide Production." In 7th International Students Science Congress. Izmir International guest Students Association, 2023. http://dx.doi.org/10.52460/issc.2023.045.

Повний текст джерела
Анотація:
Graphene oxide (GO) consists of one or several stacked graphene structures equipped with various functional groups. It has applications in many areas such as biomaterials, energy storage. sensors and photocatalytic degradation thanks to its high surface area, adjustable band gap and dispersibility in various solvents. Although there are various production techniques for GO synthesis, Improved Hummer’s Method stands out with its high efficiency and controllable production parameters. In this method, graphite is oxidized after intercalation with various acids and GO is obtained by exfoliation in the next stages. The effects of production parameters such as oxidation time, oxidant type, oxidant amount, drying processes are generally investigated in Hummer's method. In this study, the effect of oxidation time on GO structure was investigated. In this context, GO was synthesized with various oxidation times by using Modified Hummer's Method. Then, the structural and optical properties of GO were investigated by X-Ray diffraction (XRD), Fourier-Transform infrared spectroscopy (FTIR) and UV-Visible Light spectrophotometer (UV-Vis). The results showed that there is an optimum oxidation time for the oxidation degree of GO structure.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Chirila, Laura, Marcela Corina Rosu, Sabina Olaru, Cristian Tudoran, Dragos-Viorel Cosma, Alexandra Urda, Alice-Ortansa Mateescu, Gheorghe Mateescu, and Georgiana Vasile. "Cotton fabrics coated with Ag-TiO2 and Ag-TiO2/reduced graphene oxide nanocomposites." In The 8th International Conference on Advanced Materials and Systems. INCDTP - Leather and Footwear Research Institute (ICPI), Bucharest, Romania, 2020. http://dx.doi.org/10.24264/icams-2020.i.6.

Повний текст джерела
Анотація:
Ag-TiO2 and Ag-TiO2/reduced graphene oxide nanopowders were deposited onto 100% cotton fabrics via electrostatic spraying method. The surface of cotton fabrics was pre-treated by plasma at atmospheric pressure using argon and nitrogen mixture. The as-prepared cotton fabrics were characterized in terms of structural and optical properties by X-ray diffraction (XRD) and optical reflectance measurements. The photocatalytic self-cleaning ability of Ag-TiO2 and Ag-TiO2/reduced graphene oxide coated cotton fabrics was evaluated by the photo-discoloration of methylene blue and berries juice stains, under 6 h simulated visible light irradiation. The combined functionalized coating on cotton fabrics demonstrated an improved photocatalytic effect compared with untreated cotton fabrics. The antimicrobial activity of Ag-TiO2 and Ag-TiO2/reduced graphene oxide coated cotton fabrics was tested against the Staphylococcus aureus and Candida albicans test strains as model microorganism of skin bacteria and fungi, respectively. An antimicrobial effect against the Staphylococcus aureus is observed even if the inhibition zone is not present. Untreated fabrics showed no antibacterial activity. No inhibitory effect on fungi colony growth was observed.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Wang, Wentai, Gabriel Levi, Moses O.Tade, and Qin Li. "Evaluation of Photocatalytic Activity of Co3O4/Graphene Composite." In 2015 International Conference on Materials, Environmental and Biological Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/mebe-15.2015.129.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Також вас можуть зацікавити розширені добірки на тему "Graphene - Photocatalysis" для конкретних типів джерел:
Статті в журналах Дисертації
Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!

До бібліографії