Littérature scientifique sur le sujet « N-Doped titania »
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « N-Doped titania ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Articles de revues sur le sujet "N-Doped titania"
1
Noguchi, Shinnosuke, Toru Tokutome et Shinji Iwamoto. « Nitrification of Nb-Modified Titanias Prepared by the Solvothermal Method and their Photocatalytic Activities under Visible-Light Irradiation ». Key Engineering Materials 596 (décembre 2013) : 43–49. http://dx.doi.org/10.4028/www.scientific.net/kem.596.43.
Texte intégralRésumé :
Niobium modified titania samples were prepared by thermal reaction of titanium tetraisopropoxide and niobium pentaethoxide in 1,4-butanediol at 300 °C (solvothermal method), and the products were nitrified in an NH3 flow at 600 °C. The physicochemical property of the thus-obtained N-and Nb-co-doped titanias and visible-light response photocatalytic activity of FeOx-loaded N-and Nb-co-doped titanias were investigated. The N-and Nb-co-doped titanias had larger absorptions in the visible-light range as compared to the only N-doped titania samples. In ESR spectra of the Nb-modified TiO2 samples annealed at 300 °C after the nitrification, signals due to Ti3+ and oxygen vacancies, which accelerate the recombination of the photo-generated electrons and holes, were clearly observed. On the other hand, for the N-and Nb-co-doped titanias annealed at 500 °C, the signals due to Ti3+ and oxygen vacancies decreased significantly. Actually, the FeOx-loaded N-and Nb-co-doped samples annealed at 500 °C exhibited a higher photocatalytic activity for a photocatalytic decomposition of acetaldehyde under visible-light irradiation.
2
Oh, Han Jun. « Synthesis of N Doped Titania Photocatalyst by Using an Electrochemical Oxidation of TiN Layer ». Advanced Materials Research 651 (janvier 2013) : 302–5. http://dx.doi.org/10.4028/www.scientific.net/amr.651.302.
Texte intégralRésumé :
In order to improve the photocatalytic efficiency, the N doped anodic titania film for photocatalyst was synthesized by anodic oxidation of TiN layer in sulfuric electrolyte, and the photocatalytic properties of N doped TiO2layer were investigated. During the oxidation process of the TiN layer, nitrogen was doped into the anodic titania film due to the change of the titanium nitride layer to TiO2layer film. In the evaluation of dye degradation, N doped titania catalyst shows much higher efficiency than non-doped titania film.
3
Guo, Si Yao, Bo Chi, Jin Bing Sun, Feng Lu Wang, Lin Yang, Feng Zhang et Song Han. « Comparison of the Photocatalytic Activity of N-Doped, P-Doped Titania under Solar Light Irradiation ». Advanced Materials Research 113-116 (juin 2010) : 2141–44. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.2141.
Texte intégralRésumé :
P-, N-doped titania were synthesized by the direct hydrothermal method, which phosphorus from phosphoric acid and the following nitridation from urea solution. The resulting materials were characterized by XRD, XPS analysis, and their photocatalytic activities were tested by the solar light irradiation. N-doping titania resulted in the band-gap narrowing with improved photocatalytic activity. However, the phosphated titania exhibited higher photocatalytic activity than the N-doped one, but with larger band-gap energy.
4
Shu, Zhan, Tao Zeng et Hou Juan Liu. « Hydrothermal Treatment and its Influence on the Structure of Nitrogen Doped Titania ». Advanced Materials Research 393-395 (novembre 2011) : 1255–58. http://dx.doi.org/10.4028/www.scientific.net/amr.393-395.1255.
Texte intégralRésumé :
N-doped titania was synthesized by a one step hydrothermal method, which is characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The samples prepared by hydrothermal method demonstrate higher photocatalytic activity toward the degradation of methylene blue under xenon lamp which has similar spectra to solar light, and also is much superior to that of the commercial P25. In addition, the samples prepared by hydrothermal treatment could severely influence the crystal lattice structure. Morever, N-doped titania can further enhacnce the photocatalytic activity effectively, and hydrothermal treatment is a very suitable method for the synthesis of N-doped titania. This excellent performance could endow the as-prepared P-doped titania potential in purifying wastewater.
5
Chen, Guang Sheng, Si Yao Guo, Feng Zhang et Song Han. « Visible-Light-Driven TiO2 Catalysts Doped with Two Different Nonmetal Species by Hydrothermal Method ». Advanced Materials Research 183-185 (janvier 2011) : 591–94. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.591.
Texte intégralRésumé :
The doping TiO2 were prepared by hydrothermal method with two different nonmetal, that is N-doped, and N, S codoped. The resulting materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). According to the test result, nitrogen and sulfur co-doped titania give a higher photocatalytic activity in the degradation of organophosphorus pesticide. It was evidenced that the incorporation N in the anatase titania lattice in the form of O–Ti–N linkages. However, we compared with N-doped and N, S codoped it was no reservation to conclude that N, S codoped titania exhibit the further enhanced photocatalytic activity.
6
Tseng, Yao-Hsuan, Chien-Sheng Kuo, Chia-Hung Huang et Yuan-Yao Li. « Preparation of Visible-Light-Responsive Nitrogen-carbon Co-doped Titania by Chemical Vapor Deposition ». Zeitschrift für Physikalische Chemie 224, no 06 (1 juillet 2010) : 843–56. http://dx.doi.org/10.1524/zpch.2010.5512.
Texte intégralRésumé :
AbstractNitrogen-doped titania (N-doped TiO2) and nitrogen-carbon co-doped titania (N-C-doped TiO2) were prepared in metal-organic chemical vapor deposition (MOCVD) processes under the controlled reaction atmosphere. The N-doped TiO2 and N-C-doped TiO2 with anatase phase were prepared at 600Â oC under N2-O2-NH3 and N2-NH3 atmospheres respectively. The N-C-doped TiO2 exhibited the high photocatalytic activity for the oxidation of NO under visible-light illuminations. The chamber atmosphere in the MOCVD process plays an important role on the surface lattice structure and nitrogen and carbon content of TiO2. The nitrogen and carbonaceous species on the TiO2 surface, evidenced from X-ray diffractometry (XRD), UV-VIS, and Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), were inferred as important factors for narrowing band gap of titania and enhancement of its visible-light-responsive activity.
7
Guo, Si Yao, Bo Chi, Jin Bing Sun, Feng Lu Wang, Lin Yang et Song Han. « Preparation, Characterization of N, P Codoped TiO2 Nanoparticles with their Excellent Photocatalystic Properties ». Advanced Materials Research 113-116 (juin 2010) : 2162–65. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.2162.
Texte intégralRésumé :
Phosphor and nitrogen co-doped titania were prepared by hydrothermal method with phosphorous acid and ammonia as the P and N sources, respectively. The resulting materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). Phosphor and nitrogen co-doped titania give a higher photocatalytic activity in the degradation of methylene blue (MB) under solar light irradiation. It was evidenced that the incorporation of P and N in the anatase titania lattice in the form of O–Ti–N, O–P–N, and Ti–O–P linkages. After photocatalytic properties studies, we can conclude that N, P codoped titania exhibit the further enhanced photocatalytic activity.
8
Wang, Jia, Chenyao Fan, Zhimin Ren, Xinxin Fu, Guodong Qian et Zhiyu Wang. « N-doped TiO2/C nanocomposites and N-doped TiO2 synthesised at different thermal treatment temperatures with the same hydrothermal precursor ». Dalton Trans. 43, no 36 (2014) : 13783–91. http://dx.doi.org/10.1039/c4dt00924j.
Texte intégral
9
Hu, Yulong, Fu Dong, Hongfang Liu et Xingpeng Guo. « Influence of Pt and Pd Modification on the Visible Light Photocatalytic Activity of N-Doped Titania Photocatalysts ». Journal of Nanoscience and Nanotechnology 16, no 4 (1 avril 2016) : 3570–76. http://dx.doi.org/10.1166/jnn.2016.11874.
Texte intégralRésumé :
Pd and Pt modified N-doped titania nanoparticle powders were prepared by a facile sol–gel method. Nitrogen doping and metal modification were carried out simultaneously during the preparation process. The as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy and X-ray photoelectron spectroscopy (XPS). The visible light photocatalytic activities of the asprepared samples were evaluated by analyzing their effect on the photocatalytic decomposition of methyl orange (MO). The chemical state of the metal is the key factor determining the performance of metal modified N-doped titania. The Pd used to modify the N-doped titania (Pd-NT) in our study was of the PdOx(x≤2) species, which increased the absorbance in the visible light region, decreased the recombination of photo-generated electron–hole pairs, and resulted in a significant enhancement in the visible light photocatalytic activity. The Pt species used to modify the N-doped titania (Pt-NT) was mainly in the metallic state, which resulted in a decrease in the absorbance in the visible light region, and an increase in the recombination of photo-generated electron–hole pairs. Pt modification led to a deterioration in the visible light photocatalytic activity of the material.
10
Zeng, Tao, Hou Juan Liu et Zhan Shu. « Discussion the Mechanism of Sulfur and Phosphorus Doped TiO2 ». Advanced Materials Research 393-395 (novembre 2011) : 1157–60. http://dx.doi.org/10.4028/www.scientific.net/amr.393-395.1157.
Texte intégralRésumé :
Environmental pollution has become one of the most serious problems with the development of the world. TiO2 has caused great concern due to its excellent effort on the environmental purification and solar energy conversion. N, S-doped titania were prepared by a one-pot hydrothermalmethod using urea and sulfourea as precursor of nitrogen and sulfur. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of them was evaluated for the degradation of methylene blue under xenon lamp which has similar spectra to solar light. The preparation methods and doping mechanism of the nitrogen-doped TiO2 are discussed. Morever, N, S-codoped titania can further enhacnce the photocatalytic activity effectively, This excellent performance could endow the as-prepared P-doped titania potential in purifying wastewater.
Thèses sur le sujet "N-Doped titania"
1
Sacco, Olga. « Photocatalytic oxidation of organic pollutants under visible light irradiation : from N-doped tio2 photocatalysts to the design of a continuous fixed bed reactor ». Doctoral thesis, Universita degli studi di Salerno, 2015. http://hdl.handle.net/10556/1939.
Texte intégralRésumé :
2013 - 2014As a consequence of the rapid growth of population in urban areas, water use and reuse has become a major concern, leading to an urgent imperative of developing effective and affordable technologies for the treatment of water and wastewater. Traditional methods for water treatment are usually based on physical and biological processes but, unfortunately, some organic pollutants, classified as bio-recalcitrant, are not biodegradable. In this way heterogeneous photocatalysis may become an effective water treatment technology to remove organic pollutants hardly oxidised by conventional techniques. Photocatalysis represents one of the main challenges in the field of treatment and decontamination of water and air, because it is able to work at ambient temperature and atmospheric pressure. Heterogeneous photocatalysis is a catalytic process that uses the energy associated to a light source to activate a catalyst with semiconducting properties. The most common used photocatalyst is titanium dioxide (TiO2), which is able to oxidize a wide range of toxic organic compounds to harmless compounds such as CO2 and H2O. However, the following major factors limit both photocatalytic efficiency and activity of TiO2: a) the band gap of anatase TiO2 is 3.2 eV, i.e. it absorbs light in the UV region, so that only a small portion (5%) of sunlight can be used for a photocatalytic process. This is a great limitation in its use as photocatalyst for the conversion of solar into chemical energy; b) as in all semiconductors, photogenerated electron-hole couples undergo fast recombination in competition with charge transfer to adsorbed species on the catalyst surface; c) the use of slurry reactors limits the industrial applications of photocatalysis, since the necessary separation of catalyst powders after liquid phase reactions is troublesome and expensive. In this context, during this PhD project different routes have been explored to go beyond these limitations: 1. With respect to the use of visible light irradiation, doping with anions belonging to the p-block was investigated in recent years to sensitize TiO2 towards visible light, either by introducing newly created mid-gap energy states, or by narrowing the band gap itself. However, the role of titania dopants such as N, C, B, S, P, I and F is still not completely understood. The insertion of dopants in the crystalline structure of TiO2 may induce light absorption in the visible region, but also increases the rate of the undesired recombination of photogenerated charge carriers. This effect becomes relatively lower if the crystallinity of the oxide structure is higher... [edited by Author]
XIII n.s.
2
Moreira, Elizabeth Lima. « Síntese e caracterização de TiO2 puro e modificado para aplicações ambientais ». Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=6519.
Texte intégralRésumé :
Fotocatalisadores baseados em nanopartículas de dióxido de titânio modificados fornecem soluções em potencial para a mineralização de poluentes orgânicos em meio aquoso. Agentes modificadores têm sido amplamente investigados com o objetivo de promover a fotoativação pela luz visível. Foram estudadas a nível fundamental até aqui, as modificações estruturais, texturais e óticas causadas pela introdução de silício e nitrogênio na rede da titânia. Titânias puras (TiO2) e modificadas nanoestruturadas, particularmente titânias modificadas com silício (TiO2-SiO2), com razões atômicas Si/Ti de 0,1, 0,2 e 0,3 foram sintetizadas pelo método sol-gel a partir da hidrólise ácida de isopropóxido de titânio(IV) e tetraetoxisilano. As metodolo-gias sintéticas desenvolvidas tentaram aderir aos princípios da Química Verde, dispensando o uso de atmosfera inerte e temperatura e pressão elevadas, o que foi alcançado utilizando-se, principalmente, a agitação ultrassônica. Titânias modificadas com silício e dopadas com ni-trogênio (TiO2-SiO2-N) foram obtidas a partir do pré-tratamento de TiO2-SiO2 a 500 C ao ar e então submetidas ao fluxo de amônia (NH3) a 600 C por 1-3 h e, após resfriamento, foram recozidas a 400 C ao ar. Amostras distintas foram caracterizadas, na forma de pó seco e após calcinação entre 400600 C, por difração de raios X, adsorção de nitrogênio, microscopia eletrônica de varredura e espectroscopia de refletância difusa no UV-Visível. As titânias pu-ras, obtidas principalmente variando-se a razão de hidrólise, foram cristalizadas na forma de anatásio como fase predominante até 600 C, além de traços de brookita presente até 500 C. O rutilo foi identificado a partir de 600 C como fase minoritária, embora apresentando tama-nhos de cristal significativamente maiores que os estimados para o cristal de anatásio. As titâ-nias modificadas com até 20% de silício apresentaram notável estabilidade térmica, evidenci-ada pela presença exclusiva de anatásio até 900 C. Foi também observado o aparecimento de macroporos com diâmetro médio em torno de 55 nm após calcinação a 400 C, diferentemente do que se observou nas amostras em geral. A introdução de baixo teor de silício assegurou às titânias calcinadas valores elevados de área específica, atribuído ao efeito de contenção acentuada na taxa de crescimento do cristal. As titânias modificadas com silício e as titânias puras obtidas com taxa de hidrólise 25:1 para a razão H2O : Ti apresentaram mesoporos com diâmetros médios de mesma dimensão do cristal. As titânias modificadas com silício e dopa-das com nitrogênio apresentaram absorção na região visível entre 400-480 nm, com discreta redução da energia de band gap para as transições eletrônicas consideradas. Titânias calcina-das a 300−400 C apresentaram desempenho fotocatalítico semelhante ao TiO2 P25 da De-gussa sob irradiação UV, na degradação do azo corante Reactive Yellow 145 em soluções a-quosas em pH 5 a 20 1CPhotocatalysts based on modified titanium dioxide nanoparticles yield potential solutions for the mineralization of organic pollutants in aqueous media. Modifiers agents have been exten-sively investigated with the aim of promoting photoactivation by visible light. In a fundamen-tal level so far, structural, textural, and optic modifications caused by inserting silicon and nitrogen in the titania lattice, were studied. Nanostructured pure and modified titania (TiO2), mainly modified titania with silicon (TiO2-SiO2), with atomic ratios, Si/Ti, of 0.1, 0.2, and 0.3, were synthesized by the sol-gel method acid hydrolysis of titanium(IV) isopropoxide and tetraoxisilane. The developed synthetic methodologies tried to adhere to the Green Chemistry principles, not being necessary the use of inert atmosphere and elevated temperature and pressure; that was achieved, mainly, by the use of sonication. Silicon-modified titania doped with nitrogen (TiO2-SiO2-N) were obtained by pre-treating TiO2-SiO2 at 500 C in a air stream, then at 600 C in an ammonia (NH3) stream for 1-3 h and, after cooling, annealing at 400 C in a air stream. Distinct samples were characterized as a dry powder, after calcination at 400600 C, by X-ray diffraction, nitrogen adsorption, scanning electronic microscopy, and UV-Visible diffuse reflectance spectroscopy. Pure titania, primarily obtained by varying the hydrolysis ratio, were predominantly crystallized as anatase up to 600 C with traces of broo-kite present up to 500 C. Rutile was identified over 600 C as a minor phase, but presenting crystal sizes significatively larger than the estimated ones for anatase crystals. Silicon-modified titania up to 20% silicon showed a remarkable thermal stability, highlighted by the sole presence of anatase up to 900 C. It was also observed the formation of macropores with an average diameter of 55 nm after calcination at 400 C, unlike the other samples. Small contents of silicon promoted high surface areas in the calcinated titania, probably due to the a pronounced containment of the crystals growth rate. Pure and silicon-modified titania ob-tained with a hydrolysis ratio (H2O:Ti) of 25:1 presented medium mesopores with the same size of the crystals. Silicon-modified titania doped with nitrogen showed visible absorption in the 400-480 nm range, and a slight decrease of the band gap energy for the electronic transi-tions considered. Titania calcinated at 300-400 C presented a photocatalytic performance similar to Degussas P25 under UV irradiation, in the degradation of the azo dye Reactive Yellow 145 in aqueous solutions at pH 5 and 201C
3
Upadhyaya, Ashraya. « Nitrogen Doped Titanium Dioxide in the Photocatalytic Degradation of Methylene Blue ». ScholarWorks@UNO, 2018. https://scholarworks.uno.edu/honors_theses/120.
Texte intégralRésumé :
Titanium dioxide(TiO2) is a stable, effective and well-known photocatalyst for degradation of pollutants. However, its practical applications are limited due to the need for energy higher than 3.2 eV, or a wavelength lower than 390 nm (high frequency waves, ultraviolet and above) hindering its ability to effectively work in the visible light region (about 400 nm to 700 nm). Nitrogen-doped TiO2 (N-TiO2) has garnered some attention as a photocatalyst as it appears to work even in the visible light region. This could allow the utilization of a larger part of the solar spectrum. This thesis presents the results of photocatalytic degradation of methylene blue (MB) carried out under simulated visible light by using TiO2 and N-TiO2(doped in the lab) to evaluate and compare their efficiencies under similar conditions.
4
Liu, Yu-Ting, et 劉宇庭. « Photocatalytic study of nanocrystalline N-doped titania under the visible light ». Thesis, 2006. http://ndltd.ncl.edu.tw/handle/2sa2q5.
Texte intégralRésumé :
碩士國立臺北科技大學
環境規劃與管理研究所
94
Photochemical reactions catalyzed by semiconductors have been investigated extensively in the degradation of toxic organic pollutants, in organic synthesis and in energy conversion and storage. Titania is a semi-conducting photocatalyst. It can decompose the organic pollutant by irradiation under UV light. This study is divided to prepare TiO2-xNx by calcined Degussa P-25 and NH4Cl. The final propose is decreased the bandgap of TiO2, and let it can be catalyzed in the visible light. This study demonstrates a simple route for the preparation of nanocrystalline N-doped titania by calcined with ammonia chloride. This study have two important parameters: calcined temperature(T) and the ratio of TiO2 to NH4Cl(R). The N-doped titania we made was characterized by ESCA, XRD, BET and TEM etc. The wavelength of absorption of N-doped we prepared by calcination with ammonia chloride was shifted to the range of visible light.The ESCA measurement showed that nitrogen was surely doped in the titanium oxide, and the highest nitrogen content in TiO2-xNx is 11.83%. the sample is RT-1:6-400. The XRD measurement showed that Anatase phase easily transformed to Rutile phase at 500℃ and above. The crystalline transformed rate become higher by the higher calcined temperature and higher ratio of TiO2 to NH4Cl. The best photocatalytic activity in the degradation of methylene blue is obtained at the N loading about 11.83at%. The film exhibits the degradation of methylene blue with a rate-constant(k) about 0.0512 h-1 and decrease 150 hours to remove the methylene blue. Final, the RT-1:6-400 have the best efficiency photacatalisis is. It is sure the the NH4Cl is a nice material to be the N source by HCl(g) produce in the high calcined temperature with TiO2 and NH4Cl.
5
Li, Yan-Chan, et 李彥志. « Photocatalytic study of nanocrystalline Fe N co-doped titania under the visible light ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/7es7c4.
Texte intégralRésumé :
碩士國立臺北科技大學
環境工程與管理研究所
97
Photochemical reactions catalyzed by semiconductors have been investigated extensively in the degradation of toxic organic pollutants, in organic synthesis and in energy conversion and storage. Titania is a semi-conducting photocatalyst. It can decompose the organic pollutant by irradiation under UV light. This study is divided to prepare TiO2-xNx by calcined Degussa P-25 and NH4Cl. The final propose is decreased the bandgap of TiO2, and let it can be catalyzed in the visible light. This study demonstrates a simple route for the preparation of nanocrystalline N-doped titania by calcined with ammonia chloride. This study have two important parameters: calcined temperature(T) and the ratio of TiO2 to NH4Cl(R). The N-doped titania we made was characterized by ESCA, XRD, BET and TEM etc. The wavelength of absorption of N-doped we prepared by calcination with ammonia chloride was shifted to the range of visible light.The ESCA measurement showed that nitrogen was surely doped in the titanium oxide, and the highest nitrogen content in TiO2-xNx is 11.83%. the sample is RT-1:6-400. The XRD measurement showed that Anatase phase easily transformed to Rutile phase at 500℃ and above. The crystalline transformed rate become higher by the higher calcined temperature and higher ratio of TiO2 to NH4Cl. The best photocatalytic activity in the degradation of methylene blue is obtained at the N loading about 11.83at%. The film exhibits the degradation of methylene blue with a rate-constant(k) about 0.0512 h-1 and decrease 150 hours to remove the methylene blue. Final, the RT-1:6-400 have the best efficiency photacatalisis is. It is sure the the NH4Cl is a nice material to be the N source by HCl(g) produce in the high calcined temperature with TiO2 and NH4Cl.
6
Chang, Hsin-chieh, et 張歆杰. « Growth of N-F co-doped titania nanoparticle and applied on dye-sensitized solar cell ». Thesis, 2008. http://ndltd.ncl.edu.tw/handle/b675w5.
Texte intégralRésumé :
碩士國立中山大學
電機工程學系研究所
96
Using liquid phase deposition (LPD) fluorine nitrogen altogether doping porous titanium dioxide nanoparticle, general has not doped the titanium dioxide to be able the step to be 3~3.2eV, is opposite to the absorption spectrum for ultraviolet ray 380nm about, but sunlight energy only then 6% in ultraviolet ray, but the visible light has occupied about 52% energy, because grows the titanium dioxide which comes out mainly is applies in the light catalyst and the solar cell, all hoped may enhance to the luminous energy absorption, therefore only then dopes the fluorine, the nitrogen in the titanium dioxide, the goal is in order to adjust the titanium dioxide the light to absorb the boundary (optical absorption edge), at present dopes the method can dope the impurity only then minority produces the key with the titanium dioxide to binding thus result not well, penetrates ammonium hexafluorotitanate and the boric acid by the liquid phase sedimentation mixes under 40 degrees grows ammonium oxofluorotitanate discoid crystal, in the middle of this forerunner fills the very many fluorine nitrogen, after annealing and then produces the titanium dioxide to penetrate the fluorine nitrogen which the ESCA analysis contains compared to, again applies in the solar cell when can observe the annealing temperature differently when remains the fluorine nitrogen which and the key ties to the solar cell efficiency. At present the titanium dioxide light absorbs the boundary to be possible to reach the blue light region, applies the porous titanium dioxide in the dye sensitization solar cell anode, present fill factor may reach about 29.6%.
7
Chen, Chun-Wei, et 陳俊瑋. « Visible light photocatalysis and bactericidal activity of silver containing N-doped titania films by reactive sputtering ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/g3zuac.
Texte intégralRésumé :
碩士國立東華大學
材料科學與工程學系
100
In this study, a reactive magnetron sputtering system was used to deposit TiO2 and various silver and nitrogen/TiO2 multilayered films. Subsequently the films were annealed in N2 at 500oC for 1 hour. The structure and crystallinity of the Ag and TiOxNy multilayered films were determined by XRD. The morphology and thickness of the films were observed by FE-SEM. The XPS was used to measure the concentration of silver and nitrogen in the films. The absorption spectra of the films were analyzed by the UV-vis spectrotometer. The photocatalytic efficiency properties of the films under visible-light illumination were evaluated by measuring the decomposition rate of methylene blue in aqueous solution. Escherichia coli (E-coli) was chosen for in-vitro anti-bacterial analyses. Reactive magnetron sputtered films of TiO2 , TiOxNy and various Ag and TiOxNy nanocomposites were studied. Upon annealing, Ag nanoparticles precipitated and emerged on the TiOxNy film surface, which increased the overall surface area. The Ag/TiO2 films containing over 1.1 at% Ag possess good antibacterial rate. The films containing ~4.2 at% of nitrogen can effectively enhance its photocatalytic activity under visible light, but too much nitrogen content will deteriorate its anatase phase, which results in poor photocatalytic activity. From the performance of TiOxNywith and without Ag , silver not only increase absorption of visible light but plays the role of electron capture to reduce the electron-hole pair recombination, and enhance the photocatalytic activity. The best photocatalytic activity is obtained at the largest nitrogen and silver loading about 4.16 and 1.1 at % , then annealed in N2 at 500oC for 1 hour . The film exhibits the degradation of methylene blue with a rate-constant (k) about 0.055 h-1 and retaining 22.5o water contact angle on the surface under visible light illumination and good antibacterial rate over 80%. TiO2 film can protect the silver nanoparticle and achieve reuse effect.
8
Pelaschi, Mohammad Ali. « Synthesis and characterization of nitrogen-doped titanium oxide nanoparticles for visible-light photocatalytic wastewater treatment ». Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/10140.
Texte intégralRésumé :
TiO2 nanoparticles are one of the most suitable materials for photocatalysis, specifically for water and air treatment and removal of a wide variety of organic pollutants such as dyes, aromatic compounds, and chlorinated aromatic compounds. Methods of synthesis of TiO2 are generally categorized in two main classes of wet chemical, and dry methods. Wet chemical methods generally provide a better control over size, size distribution, and shape; all of which significantly affect photocatalytic performance of the produced nanoparticles. Despite its advantages over other semiconductor photocatalysts, wide band-gap of titania restrains its photocatalytic activity to only UV light, which only makes up to 5% of the light reaching surface of the earth. To induce visible-light activity, titania has been doped by different dopants, including transition metal-dopants such as Fe, and Co and non-metal dopants such as N, and C. Nitrogen has been shown to be a better dopant, providing a suitably placed energy state within the band-gap of TiO2, and not suffering from issues related to transition-metal dopants such as low thermal and physical stability and high electron-hole recombination rates. To dope titania with nitrogen, one could add the nitrogen source together with other precursors during synthesis, referred to as wet chemical doping methods, or anneal the synthesized titania nanoparticles under a flow of ammonia at high temperatures, referred to as dry doping methods. While different doping methods have been studied individually, the author maintains that there has been an absence of research comparing the effectiveness of these methods, on photocatalytic performance of N-doped TiO2 within a consistent experiment. In this research TiO2 nanoparticles were synthesized by a facile, inexpensive sol-gel method, and doping was done by wet chemical methods, dry methods, and a combination of both these methods. Visible-light photocatalytic activity of these nanoparticles was evaluated by their efficiency in degradation of methyl orange. The results show wet doping methods increase the efficiency of titania nanoparticles more than dry doping, or combination of both. Further investigation showed that the main reason for higher activity of wet chemically doped nanoparticles is due to their higher available surface area of 131.7 m2.g-1. After normalizing the available surface area, measured by the BET method, it was shown that a combination of wet chemical doping, and dry doping at 600 °C result in the most active nanoparticles, but high temperature dry doping severely decreases the surface area, lowering the overall efficiency of the product. Additionally, N-doped TiO2 nanoparticles were synthesized using a simple hydrothermal method, in which the nitrogen source was used not only to dope, but also to control shape, size, size distribution, and morphology of the titania nanoparticles, and to induce aqueous colloidal stability. It was shown that addition of triethylamine during the synthesis, results in ultra-small, colloidally stable, cubic TiO2 nanoparticles, while using triethanolamine results in formation of TiO2 pallets, assembled into spherical, rose-like structures. The synthesized nanoparticles show impressive efficiency in visible-light removal of phenol, 4-chlorophenol, and pentachlorophenol, achieving 100% degradation of a 100-ppm phenol solution in 90 min, more than 98% degradation of a 20-ppm 4-chlorophenol solution in 90 min, and 97% degradation of a 10-ppm pentachlorophenol in 180 min with 500 ppm loading of the catalyst in all cases. Moreover, synthesized nanoparticles showed no sign of deactivation after 5 consecutive runs, removing 4-chlorophenol, showing their reusability.Graduate
9
Lai, Chih-Hao, et 賴志豪. « Preparation of N Doped Indium Titanium Composite and the Evaluation of Photocatalytic Properties ». Thesis, 2013. http://ndltd.ncl.edu.tw/handle/12484182030343658954.
Texte intégralRésumé :
碩士國立高雄應用科技大學
化學工程與材料工程系博碩士班
101
This study synthesized indium titanium composite (TiO2-In2O3) nanoparticles via sol-gel method. TiO2-In2O3 was modified by urea and TiO2-In2O3/N was formed. The decolorization percentage of C.I. Reactive Red 2 (RR2) was used to determine the photocatalytic activity of TiO2-In2O3 and TiO2-In2O3/N systems. The prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) specific surface area analysis, UV–vis spectroscopy (UV–vis), zeta potential, thermal gravity analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The effects of the Ti/In ratio, Ti/N ratio, calcination temperature, photocatalyst dose, RR2 concentration and light wavelength on RR2 decolorization by TiO2-In2O3 and TiO2-In2O3/N were evaluated. The phases of prepared photocatalysts were mainly rutile. Further, the lower Ti/In ratio in TiO2-In2O3 generated the higher anatase phase percentage. Compared with undoped TiO2-In2O3, spectra show that the absorption edge shifted to a longer wavelength after N doping. Adding urea reduced the surface area of the photocatalyst and increased the size of indium titania composite particles. The XPS characterization confirmed the Ti-O and In-O in the TiO2-In2O3 and TiO2-In2O3/N systems and in the TiO2-In2O3/N forming the Ti-N-O. The pyrolysis temperature of TiO2-In2O3/N was 753 K and the molar ratio N/Ti was determined as 0.35. The isoelectric point of TiO2, In2O3, TiO2-In2O3 and TiO2-In2O3/N was 4.74, 6.54, 4.90 and 4.75, respectively. The RR2 decolorization efficiency followed the order of 254 nm > 410 nm in all tested systems. Moreover, the RR2 decolorization rate reduced as RR2 concentration increased; conversely, RR2 decolorization rate increased as the photocatalyst dose increased. The TiO2-In2O3 and TiO2-In2O3/N was photoexcited by UV and visible-light irradiation; however, TiO2-In2O3 was only photoexcited by UV irradiation. The efficiency of TiO2-In2O3/N was better than TiO2-In2O3.
10
WU, JUI-TAI, et 吳瑞泰. « Preparation of C, N and S, N co-doped Indium Titanium Composites and the Evaluation of Photocatalytic Properties ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/17272716987167710304.
Texte intégralRésumé :
博士國立高雄應用科技大學
化學工程與材料工程系博碩士班
105
TiO2 is a good photocatalyst and plays a role in the photodegradation of dyes in industrial wastewater. When TiO2 is doped with In2O3, a TiO2-In2O3 (Ti-In) composite material is formed, which can decrease the band gap in TiO2 and increase its photocatalytic activity. This study employed the sol-gel method to prepare Ti-In composite materials. Ti-In was then co-doped with carbon-nitrogen (C-N) and sulfur-nitrogen (S-N) to form new Ti-In-C-N and Ti-In-S-N composite catalysts, respectively, with the aim of increasing the photocatalytic efficiency of Ti-In. The precursors of TiO2 and In2O3 were titanium tetrachloride and indium chloride, respectively. The sources of the C, N, and S dopants were activated carbon powder, urea, and sodium thiosulfate, respectively. L-cysteine was used as a precursor for the modification of SN. The study employed a 2-step process to prepare the Ti-In-S-N composite catalysts. The first step was to prepare the Ti-In-S, before the Ti-In-S-N was synthesized with urea. During the preparation of the Ti-In-SN catalyst by doping L-cysteine, the Ti-In was modified to Ti-In-SN, in order to compare the photocatalytic activity of the two catalysts (Ti-In-S-N and Ti-In-SN). XRD analysis showed that the anatase crystalline phase ratios in Ti-In-SN, Ti-In-S-N, and Ti-In-C-N were 100 %, 64 %, and 63 %, respectively; they were all higher than Ti-In (30 %). The particle sizes of Ti-In-C-N, Ti-In-S-N, and Ti-In-SN were 33, 33, and 13 nm, respectively, all lower than Ti-In (57 nm). The band gap values of Ti-In, Ti-In-C-N, Ti-In-S-N, and Ti-In-SN were 2.97, 2.86, 2.82, and 2.75 eV, respectively, showing that co-doping Ti-In with C-N, S-N, and SN achieved the aim of decreasing the band gap of Ti-In. SEM images of Ti-In-C-N, Ti-In-S-N, and Ti-In-SN all showed a high tendency to agglomerate and all have a lamellar porous structure. TEM images showed that the particle dimensions of Ti-In-C-N, Ti-In-S-N, and Ti-In-SN were 25-50 nm, 20-50 nm, and 15-80 nm, respectively. The XPS analysis showed that Ti-In-C-N contains Ti-O-N, Ti-N-O, and Ti-O-C bonds; Ti-In-S-N contains Ti-O-N, Ti-N-O, and Ti-O-S bonds; and Ti-In-SN was verified to be formed Ti-N-O, Ti-O-N, and Ti-O-S bonds. A Brunauer-Emmett-Teller (BET) analysis was used to quantitate the specific surface areas of Ti-In, Ti-In-C-N, Ti-In-S-N, and Ti-In-SN. The resulting values were 35.7, 35.6, 42.3, and 48.6 m2/g, respectively. C.I. Reactive red 2 (RR2) was used as a target pollutant for photocatalysis reactions to compare the photocatalytic activity of various catalysts. A 254 nm UV lamp was used as a light source and the experiment was carried out at pH 3 and 25 °C. The photodegradation reactions of the prepared Ti-In, Ti-In-C-N, Ti-In-S-N, and Ti-In-SN composite catalysts were observed to obey pseudo-first-order kinetics, with rate constants of 0.43, 1.68, 1.70, and 0.68 h-1, respectively. The specific oxygen uptake rates of RR2 photodegradation were 4.4, 7.3, and 5.3 mg O2/g-MLVSS-h, respectively. The results showed that the photoactivity of the Ti-In-C-N, Ti-In-S-N, and Ti-In-SN composite catalysts, obtained from the co-doping of Ti-In, were all higher than Ti-In, and the toxicities of the treated effluent were all lower than Ti-In. Although the photocatalytic activity of Ti-In-S-N based on a two-step synthesis was higher than Ti-In-SN, the synthesis process was relatively time-consuming.
Chapitres de livres sur le sujet "N-Doped titania"
1
Li, Yan Hong, Wen Bin Cao, Fan Yong Ran et Xiao Ning Zhang. « Photocatalytic Degradation of Methylene Blue Aqueous Solution under Visible Light Irradiation by Using N-Doped Titanium Dioxide ». Dans Key Engineering Materials, 1972–75. Stafa : Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-410-3.1972.
Texte intégral
2
Wei, Yi, Rong Liang He et Wen Bin Cao. « Hydrothermal Synthesis of Fe/N Co-Doped Titanium Dioxide and its Sterilization Activity via E. Coli under Visible Light Irradiation ». Dans High-Performance Ceramics V, 1489–92. Stafa : Trans Tech Publications Ltd., 2008. http://dx.doi.org/10.4028/0-87849-473-1.1489.
Texte intégralActes de conférences sur le sujet "N-Doped titania"
1
KUSUMAWARDANI, CAHYORINI, INDRIANA KARTINI et NARSITO. « SYNTHESIS OF VISIBLE LIGHT ACTIVE N-DOPED TITANIA PHOTOCATALYST ». Dans Proceedings of the International Conference on CBEE 2009. WORLD SCIENTIFIC, 2009. http://dx.doi.org/10.1142/9789814295048_0023.
Texte intégral
2
Fick, J., G. Vitrant, S. Pelli, G. C. Righini, M. Guglielmi et A. Martucci. « Measurements of nonlinear properties on semiconductor-doped sol-gel films ». Dans The European Conference on Lasers and Electro-Optics. Washington, D.C. : Optica Publishing Group, 1994. http://dx.doi.org/10.1364/cleo_europe.1994.cthp3.
Texte intégralRésumé :
Thin silica-titania planar waveguides doped with cadmium sulphide have been prepared on fused silica substrates using the sol-gel technique. Tetraethoxisylane (TEOS) and titanium butilate Ti(n-OBu)4 (30%) were used as precursors of the film.1 The semiconductor dopants have been introduced by adding cadmium nitrate and thiourea to the starting solution as precursors of cadmium and sulphur, respectively. The films have been produced by dipping the samples in the solution and withdrawing them at constant speed. Thereafter the samples have been densified at 300°C for 4 hours in nitrogen atmosphere in order to prevent outdiffusion of the dopants. The thickness of the films is typically about 1300 A and their refractive index is 1.63 at 633 nm.
3
Jeon, Sanghyeon, Taehong Ha, Youngwoo Kim, Hyuckchai Jung, Taewoo Lee, Kyupil Lee et Insoo Cho. « A Reduction of Off-Leakage Current of SWD (Sub-WordLine Driver) pMOSFET for NWL-Based Mobile DRAM ». Dans ISTFA 2013. ASM International, 2013. http://dx.doi.org/10.31399/asm.cp.istfa2013p0407.
Texte intégralRésumé :
Abstract We demonstrate an effective way of reducing off-leakage current in sub-wordline driver pMOSFETs with lightly-doped source/drain, where gate-induced drain leakage current is much relaxed, compared with those of asymmetric source/drain. In mobile DRAM, one of key parameters is to achieve an extremely low level of standby current in power consumption. What has been found is that an increase of offleakage current in the pMOSFET is related closely to a contact-formation process, in particular, TiSi2 in p+/n junction. When a direct contact becomes close to a source/drain region, a titanium atom in TiSi2 tends not only to diffuse into a depletion region of p+/n junction but to play a critical role in leakage current. Maximizing a distance between p+ gate and its direct contact should be emphasized in order to control offleakage current in such a pMOSFET.
4
Pangestuti, A. D., et J. Gunlazuardi. « Preparation and characterization of nitrogen-doped highly ordered titanium dioxide nanotubes (N-doped-HOTN) : How far it will improve toward the visible light response and why ? » Dans PROCEEDINGS OF THE 3RD INTERNATIONAL SYMPOSIUM ON CURRENT PROGRESS IN MATHEMATICS AND SCIENCES 2017 (ISCPMS2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5064106.
Texte intégral
5
Ignat, Madalina, Lucretia Miu, Emanuel Hadimbu, Claudiu Sendrea, Maria-Cristina Micu, Simona Maria Paunescu, Iulia Maria Caniola et Elena Badea. « The influence of TiO2 and N-TiO2 nanopowders in natural leather finishing for heritage or modern binding ». Dans 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.v.3.
Texte intégralRésumé :
The methods for processing raw hides over time, have been numerous: smoke, fat, fermented milk, egg, volcanic soils, plants (shells, fruits, leaves) and so on. The books binding with leather has its origins in the Orient and are known various types of goatskin and calfskin, tanned with sumac finished marbled (sapphire), in black (Moroccan), by floating and dyeing in various colors (Cordoba leathers). Preoccupations regarding the assurance of optimal characteristics for the binding leathers, respectively the durability of the leathers for the restoration of the patrimony objects or of the modern binding were of the most topicality in the last decades, abroad and also in our country. The paper describes the finishing of vegetable and alum tanned leather samples that have been functionalized with titanium dioxide (TiO2) or nitrogen-doped titanium dioxide (N-TiO2) nanopowders, in different concentrations. To simulate soiling in real conditions, four types of soiling agents were applied: tea, coffee, beetroot extract and pen paste. The samples were exposed to irradiation in a photoreactor with various light sources for up to 192 hours. The evaluation of the photocatalytic degradation was performed by the CIELab technique.