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Auswahl der wissenschaftlichen Literatur zum Thema „Photocatalysis Self-Cleaning“
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Zeitschriftenartikel zum Thema "Photocatalysis Self-Cleaning"
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Gryparis, Charis, Themis Krasoudaki und Pagona-Noni Maravelaki. „Self-Cleaning Coatings for the Protection of Cementitious Materials: The Effect of Carbon Dot Content on the Enhancement of Catalytic Activity of TiO2“. Coatings 12, Nr. 5 (25.04.2022): 587. http://dx.doi.org/10.3390/coatings12050587.
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The urgent demand for pollution protection of monuments and buildings forced the interest towards specific preservation methods, such as the application of photocatalytic coatings with self-cleaning and protective activity. TiO2 photocatalysts without and with a variety of carbon dots loading (TC0, TC25–75) were synthesized via a green, simple, low cost and large-scale hydrothermal method using citric acid, hydroxylamine and titanium isopropoxide (TTIP) and resulted in uniform anatase phase structures. In photocatalysis experiments, TC25 and TC50 composites with 1:3 and 1:1 mass ratio of C-dots solution to TTIP, respectively, showed the best degradation efficiency for methyl orange (MO) under UV-A light, simulated solar light and sunlight compared to TiO2, commercial Au/TiO2 (TAu) and catalysts with higher C-dot loading (TC62.5 and TC75). Treatment of cement mortars with a mixture of photocatalyst and a consolidant (FX-C) provided self-cleaning activity under UV-A and visible light. This study produced a variety of new, durable, heavy metal-free C-dots/TiO2 photocatalysts that operate well under outdoor weather conditions, evidencing the C-dot dosage-dependent performance. For the building protection against pollution, nanostructured photocatalytic films were proposed with consolidation and self-cleaning ability under solar irradiation, deriving from combined protective silica-based agents and TiO2 photocatalysts free or with low C-dot content.
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Gryparis, Charis, Themis Krasoudaki und Pagona-Noni Maravelaki. „Self-Cleaning Coatings for the Protection of Cementitious Materials: The Effect of Carbon Dot Content on the Enhancement of Catalytic Activity of TiO2“. Coatings 12, Nr. 5 (25.04.2022): 587. http://dx.doi.org/10.3390/coatings12050587.
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The urgent demand for pollution protection of monuments and buildings forced the interest towards specific preservation methods, such as the application of photocatalytic coatings with self-cleaning and protective activity. TiO2 photocatalysts without and with a variety of carbon dots loading (TC0, TC25–75) were synthesized via a green, simple, low cost and large-scale hydrothermal method using citric acid, hydroxylamine and titanium isopropoxide (TTIP) and resulted in uniform anatase phase structures. In photocatalysis experiments, TC25 and TC50 composites with 1:3 and 1:1 mass ratio of C-dots solution to TTIP, respectively, showed the best degradation efficiency for methyl orange (MO) under UV-A light, simulated solar light and sunlight compared to TiO2, commercial Au/TiO2 (TAu) and catalysts with higher C-dot loading (TC62.5 and TC75). Treatment of cement mortars with a mixture of photocatalyst and a consolidant (FX-C) provided self-cleaning activity under UV-A and visible light. This study produced a variety of new, durable, heavy metal-free C-dots/TiO2 photocatalysts that operate well under outdoor weather conditions, evidencing the C-dot dosage-dependent performance. For the building protection against pollution, nanostructured photocatalytic films were proposed with consolidation and self-cleaning ability under solar irradiation, deriving from combined protective silica-based agents and TiO2 photocatalysts free or with low C-dot content.
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Bielan, Zuzanna, Szymon Dudziak, Adam Kubiak und Ewa Kowalska. „Application of Spinel and Hexagonal Ferrites in Heterogeneous Photocatalysis“. Applied Sciences 11, Nr. 21 (29.10.2021): 10160. http://dx.doi.org/10.3390/app112110160.
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Semiconducting materials display unique features that enable their use in a variety of applications, including self-cleaning surfaces, water purification systems, hydrogen generation, solar energy conversion, etc. However, one of the major issues is separation of the used materials from the process suspension. Therefore, chemical compounds with magnetic properties have been proposed as crucial components of photocatalytic composites, facilitating separation and recovery of photocatalysts under magnetic field conditions. This review paper presents the current state of knowledge on the application of spinel and hexagonal ferrites in heterogeneous photocatalysis. The first part focuses on the characterization of magnetic (nano)particles. The next section presents the literature findings on the single-phase magnetic photocatalyst. Finally, the current state of scientific knowledge on the wide variety of magnetic-photocatalytic composites is presented. A key aim of this review is to indicate that spinel and hexagonal ferrites are considered as an important element of heterogeneous photocatalytic systems and are responsible for the effective recycling of the photocatalytic materials.
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Rocha Segundo, Freitas, Landi Jr., Costa und Carneiro. „Smart, Photocatalytic and Self-Cleaning Asphalt Mixtures: A Literature Review“. Coatings 9, Nr. 11 (24.10.2019): 696. http://dx.doi.org/10.3390/coatings9110696.
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Nowadays, there is increasing concern in transportation engineering about the use of techniques less harmful to the environment and also about road safety. Heterogeneous photocatalysis based on the application of semiconductor materials onto asphalt mixtures is a promising technology because it can mitigate air pollution and road accidents. The functionalized asphalt mixtures with photocatalytic capability can degrade pollutants, such as damaging gases and oil/grease adsorbed on their surface, from specific reactions triggered by sunlight photons, providing significant environmental and social benefits. In this article, a review of photocatalysis applied in asphalt mixtures is presented. The most important characteristics related to the functionalization of asphalt mixtures for photocatalytic applications and their corresponding characterization are presented, and the achieved main results are also discussed.
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Singh, Vishvendra Pratap, Rahul Vaish und El Sayed Yousef. „A Review on Cement-Based Composites for Removal of Organic/Heavy Metal Contaminants from Water“. Catalysts 12, Nr. 11 (09.11.2022): 1398. http://dx.doi.org/10.3390/catal12111398.
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Building materials are traditionally known for their mechanical and structural properties. As environmental pollution has risen as a huge global issue, functional building materials with environmental remediation capabilities are the demand for the present time. In this context, cement and concrete with photocatalytic and adsorbent additives were explored for air and water remediation. The usage of functional building materials for self-cleaning and air cleaning is well documented and reviewed in earlier reports. This article gives an overview of the functional building material composites used for water remediation. Numerous different approaches, such as photocatalysis, adsorption, and antimicrobial disinfection, are discussed. Among all, photocatalysis for the degradation of organic compounds and antimicrobial effect has been the most studied method, with TiO2 being the first choice for a photocatalyst. Furthermore, some reports illustrate the impact of photocatalytic filler on hydration and mechanical properties, which is important in case these are used in construction. Adsorption was most preferred for heavy metal removal from the water. This article rationalizes the current status and future scope of cement-based functional composites for water cleaning and discusses their use in water cleaning facilities or regular construction.
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Lavrenčič Štangar, Urška, Marko Kete, Urh Černigoj und Vilma Ducman. „Testing of Photocatalytic Activity of Self-Cleaning Surfaces“. Advances in Science and Technology 68 (Oktober 2010): 126–34. http://dx.doi.org/10.4028/www.scientific.net/ast.68.126.
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Due to relatively successful application of TiO2 photocatalysis in the field of self-cleaning surfaces, a reliable and appropriate quantitative method for determining the self-cleaning efficiency of the products (photocatalyst films on different supports) should be widely recognized and established. Currently, the two standard methods are based on photobleaching of methylene blue aqueous solution in contact with thin solid catalyst layer, and on photodegradation of a solid fatty deposit (e.g. stearic acid) over catalyst layer followed indirectly by water contact angle (CA) measurements. Another method proposed recently is based on the entrapment of an organic dye in a solid polymer matrix deposited over the photocatalyst layer. Upon illumination, the dye (e.g. resazurin) is reduced by the photogenerated electrons to the form of a different colour or to the bleached form. Recently, a new method for determination of self-cleaning activity of photocatalytic surfaces was developed in our laboratory. It is based on the deposition of a transparent solid layer comprising terephthalic acid over the photocatalytic surface. When such a system is irradiated, among the other degradation products also a hydroxyterephthalic acid is formed due to a reaction between photoexcited TiO2 and terephthalic acid. Hydroxyterephthalic acid is a highly fluorescent molecule and can be easily detected by HPLC-FLD or spectrofluorimeter. Many different samples were tested using this method and using the standard method based on photodegradation of a solid fatty deposit over the catalyst layer. Regarding the sample (substrate) type, the focus was given to the self-cleaning ceramic tiles coated with TiO2-SiO2 thin films that were produced in cooperation with the major manufacturer of floor ceramic tiles in Slovenia, Martex d.o.o.. In case of self-cleaning ceramics and some other sample types, the advantages of the new method over standard methods were highlighted and critically evaluated.
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Liu, Hong Quan, Fang Lian, Lin Zhang und Meng Liu. „Photocatalysis Property of Titania-Based Thin Films with Covalent Grafting PANi as Sensitizer“. Advanced Materials Research 549 (Juli 2012): 470–73. http://dx.doi.org/10.4028/www.scientific.net/amr.549.470.
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Polyaniline sensitized titania thin film were fabricated by spin-coating from Ti-precursor containing PEG as surfactant via a sol-gel technique, in which titania-sol was synthesized by hydrolysis of tetrabutyl titanate in water-alcohol solution. The films were characterized by X-ray diffraction, high resolution transmission electron microscopy, field-emission scanning electron microscopy, thermal gravity-differential scanning calorimetry, and tested under self-made photocatalysis instrument. The results showed the synthesized porous films provided the active surfaces for self-polymerization of aniline. Compared with bare TiO2 thin films, the composite films displayed a enhanced photocatalytic activity and could be the potential photocatalyst for indoor air decontamination or self-cleaning films.
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Lavrenčič Štangar, Urška, Minoo Tasbihi, Fernando Fresno, Marko Kete, Alberto Gasparotto, Chiara Maccato und Davide Barreca. „Self-Cleaning and Anti-Fogging Surfaces Based on Nanostructured Metal Oxides“. Advances in Science and Technology 91 (Oktober 2014): 39–47. http://dx.doi.org/10.4028/www.scientific.net/ast.91.39.
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Self-cleaning and anti-fogging technology is already used in a variety of the products today, among which glazing products prevail. Their function is based on the two principles, either hydrophobic (Lotus effect) or photocatalytic hydrophilic principle. In the latter case, self-cleaning action is based on the combination of photocatalysis and photoinduced superhydrophilicity, where dirt removal by uniform spreading of water over the whole surface is improved with photocatalytic decomposition of organic contaminants. There is a big room to play and a huge potential to improve the properties of existing self-cleaning and anti-fogging surfaces by designing and tailoring new nanoarchitectures of the light-activated thin films. In this lecture we report about the latest achievements and relevance of nanostructured metal oxide surfaces for specific application in photocatalytic self-cleaning. The emphasis is given to the preparation and structure-property relationship of nanocomposite materials based on TiO2 (TiO2-SiO2) and ZnO (ZnO/Co3O4). The emphasis is given also to determination of photocatalytic self-cleaning activity by quantitative and sensitive methods such as fluorescence detection of the first degradation product of terephthalic acid.
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TISMANAR, IOANA, und ANCA DUTA. „Vis-active photocatalytic composite thin films for advanced wastewater treatment“. Journal of Engineering Sciences and Innovation 7, Nr. 2 (14.06.2022): 193–202. http://dx.doi.org/10.56958/jesi.2022.7.2.193.
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Conventional wastewater treatment processes are preparing the water for discharge thus it still contains small amounts of pollutants. For re-use, advanced wastewater treatment is required and heterogeneous photocatalysis represent a viable path for removing organic pollutants at very low concentrations but still above the discharge limit. The mostly investigated photocatalyst is TiO2 that is a wide band gap semiconductor that can be activated only using UV radiation. However, for large-scale implementation of advanced wastewater treatment, there are required efficient and affordable processes, thus Vis- or solar-activated photocatalysts. Attempts on extending the photocatalytic response towards Vis are under intensive research including the development of composite structures with TiO2 matrix and various fillers that are discussed through this paper. The latest results involving carbon-based fillers are presented along with the extended use of the composites acting also as self-cleaning coatings.
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Ding, Jun. „Preparation of TiO2 Photocatalysis Antibacterial Ceramics“. Key Engineering Materials 575-576 (September 2013): 302–5. http://dx.doi.org/10.4028/www.scientific.net/kem.575-576.302.
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Among various inorganic antibacterial materials, TiO2 photocatalysis antibacterial materials possess unique properties including long lifespan, nontoxicity, high temperature resistance as well as high physical and chemical stability. More significantly, they are largely involved in many photocatalytic effects such as degradation of organics, purification of air, sewage disposal and self-cleaning.
Dissertationen zum Thema "Photocatalysis Self-Cleaning"
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Topalian, Zareh. „Nanostructured Transition Metal Oxides in Cleantech Application : Gas Sensors, Photocatalysis, Self-cleaning Surfaces Based on TiO2, WO3 and NiO“. Doctoral thesis, Uppsala universitet, Fasta tillståndets fysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-148872.
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This thesis focuses on the application of nanocrystalline transition metal oxide TiO2, WO3 and NiO thin films in new “green” building technologies. Specifically, their physicochemical properties in photocatalytic, self-cleaning and gas sensing applications are studied. There is an intimate connection between comfort issues, health, with connections to energy efficiency, leading to a need for intelligent building materials and green architecture. The importance of good indoor environment is augmented by the fact that modern man in developed countries spends some 90 % of his time inside buildings and vehicles. Poor air quality may lead to discomfort of the person inhabiting a building and in ultimately cause adverse health effects. Thin films of nanocrystalline TiO2 were prepared using reactive DC magnetron sputtering. Crystalline mesoporous films of WO3 and NiO were prepared using advanced gas deposition technique (AGD). The crystal structure, morphology, optical and chemical properties of the films were characterized by using grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy (SEM), UV/Vis spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively. The photocatalytic properties and adsorption of both organic and inorganic molecules on pure and functionalized films were probed by in situ Fourier transform infrared spectroscopy (FTIR). The gas sensing properties of sensors based on TiO2, WO3 and NiO were investigated by conductivity measurements and noise spectroscopy. It was found for the first time that NiO based thin film sensors can be used to detect H2S and NO2 at low temperatures – down to room temperature. Hybrid WO3 sensors functionalized with multiwalled carbon nanotubes (MWCNTs) were used to detect NO2, CO and NH3 gases. These hybrid gas sensors show improved recovery properties compared to unmodified WO3 sensors. TiO2 based gas sensors were able to detect low concentrations of H2S by noise spectroscopy provided that the sensors were irradiated by UV light. Furthermore we show that sulphur is photo-fixated in crystalline TiO2 films upon simultaneous SO2 gas exposure and UV irradiation. Studies of the kinetics and identity of the photo-fixated sulphur complexes show that these are formed by photo-induced reactions between oxygen and SO2 at oxygen surface vacancy sites in TiO2. The sulphur modified TiO2 films show interesting self-cleaning properties compared to the pure films.Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 739
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Ersoz, Tugce Irfan. „Application Of Semi Conductor Films Over Glass/ceramic Surfaces And Their Low Temperature Photocatalytic Activity“. Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610377/index.pdf.
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Semiconductor metal oxides can be induced by light with proper wavelength resulting in oxidation and reduction reactions for the transformation of water and oxygen molecules into active radicals. With this method, it is possible to obtain self-cleaning surfaces and products having antimicrobial properties.
The aim of this study is to develop semiconductor metal oxide thin films for multifunctional glass products and the characterization of photocatalytic self cleaning and antimicrobial properties. As semiconductor metal oxidestitanium dioxide (TiO2), tin oxide (SnO2) and their binary mixtures (TiO2-SnO2) are selected because of their abundancy, non toxic properties, stability and the ability of absorbing light close to visible range. Also the effect of metal dopants such as praseodymium (Pr), palladium (Pd), silver (Ag) and iron (Fe) was examined with these metal oxides. The colloidal solutions were synthesized by using sol-gel method in order to apply the developed method to industrial usage as applying on large surfaces. The glass substrates were coated with the colloidal solutions by dip coating and the dried samples were calcined under air flow. The best calcination condition for pure TiO2 coated thin film was determined as 400oC for 45 minutes. Surface characterization studies were performed by using UV-Visible Spectrophotometer for band gap measurement, CAM for contact angle measurement, SEM for surface morphology and tophology. The methylene blue adsorption tests were carried out and the effective surface area of the samples were predicted by the Langmuir adsorption isotherm of samples. The photocatalytic activities of the coated thin films were measured with the degradation of organic materials as red wine and methylene blue, and with the antimicrobial activity tests as counting the number of viable E.coli cells. 61.2% deactivation of methylene blue stain was achieved over SnO2 coated thin films while this was 22.1% over TiO2 coated thin films after irradiation for 180 minutes. The superior photocatalytic activity was observed with TiO2 samples doped with Pd and Ag ions. The TiO2-SnO2 coated samples performed limited photocatalytic activity which is less than the activity of SnO2 coated samples which was confirmed with surface area measurements as SnO2 coated samples had higher surface area (9.81 cm2/cm2) than TiO2-SnO2 coated samples. Surface area increased with increasing the amount of SnO2 and it was in the following order: SnO2 >
80% SnO2 + 20% TiO2 >
50% SnO2 + 50%TiO2 >
35% SnO2 + 65%TiO2 >
20% SnO2 + 80% TiO2 >
TiO2.
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Stefanov, Bozhidar. „Photocatalytic TiO2 thin films for air cleaning : Effect of facet orientation, chemical functionalization, and reaction conditions“. Doctoral thesis, Uppsala universitet, Fasta tillståndets fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-265056.
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Poor indoor air quality is a source of adverse health effects. TiO2 coatings deposited on well-illuminated surfaces, such as window panes, can be used to fully mineralize indoor air pollutants by photocatalysis. In such applications it is important to ensure stable photocatalytic activity for a wide range of operating conditions, such as relative humidity and temperature, and to avoid deactivation of the catalyst. In this thesis photocatalytic removal of the indoor-pollutant acetaldehyde (CH3CHO) on nanostructured TiO2 films is investigated, and in particular it is proposed how such films can be modified and operated for maximum performance. Catalyst deactivation can be reduced by purposefully changing the surface acidity of TiO2 by covalently attaching SO4 to the surface. Moreover, the overall photocatalytic activity on anatase TiO2 films can be improved by increasing the fraction of exposed reactive {001} surfaces, which otherwise are dominated by {101} surfaces. In the first part of the thesis mode-resolved in-situ FTIR is used to elucidate the reaction kinetics of CH3CHO adsorption and photo-oxidation on the TiO2 and SO4 – modified TiO2 surfaces. Surface concentrations of main products and corresponding reaction rates were determined. Formate is the major reaction product, whose further oxidation limits the complete oxidation to gaseous species, and is responsible for photocatalyst deactivation by site inhibition. The oxidation reaction is characterized by two reaction pathways, which are associated with two types of surface reaction sites. On the sulfate modified TiO2 catalyst fewer intermediates are accumulated, and this catalyst resists deactivation much better than pure TiO2. A hitherto unknown intermediate – surface-bound acetaldehyde dimer with an adsorption band at 1643 cm−1 was discovered, using interplay between FTIR spectroscopy and DFT calculations. The second part of the thesis treats the effect of increasing the relative abundance of exposed {001} facets on the photocatalytic activity of anatase TiO2 films prepared by DC magnetron sputtering. A positive effect was observed both for liquid-phase photo-oxidation of methylene blue, and for gas-phase photocatalytic removal of CH3CHO. In both cases it was found that the exposed {001} surfaces were an order of magnitude more reactive, compared to the {101} ones. Furthermore, it was found that the reactive films were more resilient towards deactivation, and exhibited almost unchanged activity under varying reaction conditions. Finally, a synergetic effect of SO4 – modification and high fraction of exposed {001} surfaces was found, yielding photocatalysts with sustained high activity. The results presented here for facet controlled and chemically modified TiO2 films are of interest for applications in the built environment for indoor air purification and as self-cleaning surfaces.GRINDOOR
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Austria, Gabriela Cortes. „Argamassa autolimpante para revestimento de fachadas : o efeito das propriedades fotocatalíticas do dióxido de titânio (TiO2)“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/131071.
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As fachadas das edificações, ao longo de sua vida útil, sofrem degradação devido a ataques de agentes químicos e à deposição de partículas na sua superfície. Como consequências, há perdas no desempenho de seus materiais e a desfiguração estética das fachadas por meio de manchas, implicando em ações de reparo que envolvem custos elevados. Os produtos atualmente disponíveis no mercado brasileiro com objetivo de evitar o manchamento de fachadas têm baixa eficiência, sendo que os principais deles adotam a técnica do pós-tratamento com hidrofugantes, os quais geralmente alteram a coloração do substrato e podem ser a origem de novas patologias. Usufruindo de novas tecnologias, o dióxido de titânio (TiO2) apresenta-se como material nanométrico amplamente estudado na área científica, sendo potencialmente utilizado como fotocalisador. O presente trabalho verificou a possibilidade de obtenção de superfícies autolimpantes a partir da adição de TiO2 em revestimentos de argamassa branca. Estas, a partir de propriedades fotocatalíticas do TiO2 podem ser tornar autolimpantes sob ação da radiação solar (UV) e da chuva. Foram confeccionadas argamassas de traço 1:2 e 1:3, com adições de 0%, 5% e 10% de TiO2 em relação à massa de cimento, com consistência fixa. As amostras foram aspergidas com diferentes agentes manchantes: azul de metileno, particulado de poluição, produto de corrosão, pichação; e sem manchamento (referência). Após, estas amostras foram expostas nas condições ambientais da cidade de Porto Alegre. Ao longo de 84 dias, foram realizadas leituras com espectrofotômetro portátil para avaliar o efeito autolimpante. Também foram verificadas as propriedades físico-mecânicas das argamassas. Os resultados apontaram que argamassas com adição de TiO2 necessitaram maior quantidade de água, apresentaram maior densidade no estado fresco e menor teor de ar incorporado. Ainda, a resistência à compressão foi elevada para o traço mais rico (1:2) e mantida constante para o traço pobre (1:3). Além disso, se mostraram mais claras/brancas quanto maior a porcentagem de adição. O efeito autolimpante pode ser percebido mais facilmente na mancha de azul de metileno, porém, a limpeza ocorreu tanto em argamassas com adição de TiO2, quanto em argamassas sem a adição. Em manchas que geraram uma película sobre a placa, o efeito autolimpante foi dificultado.The facades of buildings, during their lifespan, suffer degradation due to attacks of chemical agents and due to deposition of particles on their surface. As consequences, there are losses on the performance of their materials and aesthetics disfiguration of the facades by stains, implying repairing actions involving high costs. The products available nowadays on the brasilian market with the purpose to avoid the staining of the facades have low efficiency, and the main products between them adopt the technique of post-treatment with hydrophobing, which generally modify the colour of the substrate and which can originate new pathologies. Taking advantage of new technologies, the titanium dioxide (TiO2) appears as a nanometric material widely studied in the scientific area, being pottentialy used as photocatalyser. The present work has verified the possibility of obtention of self-cleaning surfaces after addition of TiO2 in white mortar coverings. Those, from photocatalyser properties of the TiO2 can become self-cleaning under the action of solar radiation (UV) and rain. There were prepared mortars of trace 1:2 and 1:3, with additions of 0%, 5% and 10% of TiO2 in relation of the cement weight, with steady consistency. The samples were sprinkled with different staining agents: methylene blue, pollution particulates, corrosion product, graffiti; and without stains (reference). After that, these samples were exposed to the ambiental conditions of the city of Porto Alegre. Through 84 days, scannings were made with portable spectrophotometer to evaluate the self-cleaning effect. The physicalmechanical properties of the mortars were also verified. The results point out that mortars with addition of TiO2 required a bigger amount of water, they presented bigger density in the fresh state and smaller contents of incorporated air. Besides, the compression resistance was high to the richest trace (1:2) and remained constant to the poor trace (1:3). Moreover, they have showed themselves more clear/white as bigger was the percentage of addition. The self-cleaning effect can be more easily noticed on the methylene blue stain, however, the cleaning occurred both in mortars with addition of TiO2 and in mortars without the addition. In stains which generate a film above the plate, the self-cleaning effect was hampered.
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PANZARASA, Guido. „Advances in sensors: the enabling roles of photocatalysis, polymer brushes and exotic characterization approaches“. Doctoral thesis, Università del Piemonte Orientale, 2016. http://hdl.handle.net/11579/80703.
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A transformative advance in the field of sensor technology has been the development of smart sensor systems. One major implication of smart sensor systems is the use of robust and reliable sensing devices. lt could appear to be trivial, but even the most intelligent system is completely useless if its sensing core does not work properly. For this reason, it is of paramount importance to develop highly efficient sensing platforms with self-calibrating, self-healing, self-compensating and selfcleaning properties. This is one of the most challenging and actual field of research, which benefited much from the "nanotechnology revolution", generating high promises especially for the development of miniaturized devices. This broad field crosses many different disciplines ranging from
chemistry to physics to materials science, with a major role played by surface science. The scope of this Thesis is to explore three different, although converging, approaches to develop such kind of sensing platforms. The enabling roles of photocatalysis, polymer brushes and of exotic characterization techniques (such as positron annihilation spectroscopy) to reach this goal are discussed. Theoretical as well as highly applicative results are described, as products of a genuine curiosity-driven approach.
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Treviso, João Pedro Marins. „Avaliação da eficiência de autolimpeza em argamassas e pastas contendo TiO2 expostas ao microclima urbano“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/142697.
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Ao longo do tempo, os revestimentos de fachada permanecem expostos a diversos agentes de degradação, sejam eles associados aos próprios materiais empregados ou a fatores externos. Tal exposição implica em manchas formadas a partir da deposição de partículas poluentes na superfície dos revestimentos, elevando seus custos para limpeza e manutenção. Uma vez que permanecem expostas à radiação solar, as fachadas se mostram atraentes ao uso de materiais fotocatalíticos, os quais catalizam a mineralização de agentes poluentes, transformando-os em produtos inócuos. A adição de dióxido de titânio (TiO2) a argamassas e concretos de cimento branco desenvolve superfícies autolimpantes, reduzindo a formação de manchas e mantendo sua coloração original ao longo do tempo. No entanto, a eficiência e a economia no uso de materiais fotocatalíticos em aplicações reais é fortemente afetada pela disponibilidade da radiação ultravioleta adequada para ativá-los. Portanto, o presente trabalho busca avaliar a capacidade autolimpante de argamassas e coberturas fotocatalíticas de TiO2 expostas a diferentes configurações de posicionamento no microclima urbano da cidade de Porto Alegre. Para isto, foram confeccionadas amostras de argamassa e coberturas de pasta ou argamassa contendo diferentes teores de TiO2, as quais foram manchadas com Rodamina B e lodo de cinzas da queima de eucalipto e, a seguir, expostas sob diferentes condições de posicionamento, voltadas para as orientações norte, sul, leste e oeste, à 0º, 45º e 90º. Ao longo do período de exposição, foram realizadas leituras cromáticas (sistema CIELab) na superfície das amostras, tendo em vista a descoloração dos manchamentos aplicados. Para aquelas manchadas com Rodamina B, a degradação do corante se mostrou mais eficiente nas argamassas com maiores teores de TiO2 e nas configurações de posicionamento que recebem maior incidência de radiação solar. As coberturas de pasta apresentaram valores mais elevados de variação de cor (ΔE) e refletância (L*), na comparação à aplicação do TiO2 como cobertura de argamassa ou incorporado à mistura − métodos os quais se mostraram resultados equivalentes.Building façades are commonly exposed to polluting agents generated by vehicles and industries exhausts, which cause stains on their surfaces and increase efforts and costs both for cleaning and maintenance. Facades are attractive to photocatalytic materials usage, which transform pollutants to innocuous products. The addition of titanium dioxide (TiO2) to white cement mortars and concretes develops self-cleaning surfaces which are capable to reduce stains and maintain their original color along the time. However, efficiency and economy in the use of photocatalytic materials in real applications are strongly affected by the availability of suitable ultraviolet radiation to activate them. This thesis aims to evaluate the self-cleaning ability of TiO2-containing mortars and coatings (paste or mortar) exposed to controlled positioning settings in the urban environment of Porto Alegre, Brazil. Mortars and coatings were prepared containing different additions of TiO2 and then were soiled by Rhodamine B (RhB) or burning ashes of eucalyptus sludge. Samples were exposed under outdoor conditions facing north, south, east and west orientations, 0º, 45º or 90º slopes. During the exposure test, discoloration effect on samples' surface was monitored by colorimetric measurements (CIELab color space) using a portable spectrophotometer. A final analysis was performed at the end of the measurements, including statistical tests. Self-cleaning ability was better seen both for higher additions of TiO2 and settings which receive higher intensities of solar radiation. Cement paste coatings showed higher values both of color change and reflectance when compared to mortar coatings or TiO2 added to the mixture − which performed equivalent results.
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Steinbergerová, Ivana. „Experimentální ověření fotokatalytického působení TiO2 v betonech“. Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-225900.
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This thesis is focused on gathering all available information on the application forms of photocatalytic TiO2 in concretes, especially in the surface layers of precast and monolithic structures. The paper describes in detail the properties of titanium dioxide alone, his special abilities, leading to a substantial improvement of the environment, through photocatalysis. Further verification methods are described photocatalytic activity of titanium dioxide and titanium dioxide application in real projects. The practical part is tested recipes of secondary coatings from the production of company Precheza a.s. Přerov.
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Garrec, Ronan. „Caractérisation photoélectrochimique de nanoparticules de dioxyede de titane déposées sur verre : application aux vitrages auto-nettoyants“. Grenoble INPG, 2001. http://www.theses.fr/2001INPG0032.
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Actuellement, le marché du bâtiment est demandeur de nouveaux matériaux, et notamment de vitrages, exigeant peu d'entretien. Pour cela les surfaces photoréactives à base de dioxyde de titane sont très bien adaptées ; soumises à un rayonnement ultraviolet, elles peuvent dégrader photocatalytiquement un grand nombre de salissures organiques et l'utilisation de nanoparticules permet d'obtenir un verre optiquement neutre. Le travail présenté porte sur la caractérisation photoélectrochimique de ces surfaces photoréactives constituées de TiO2 sous forme nanoparticulaire entouré d'un liant nécessaire à la tenue mécanique des nanoparticules. Les mesures photoélectrochimiques ont permis de caractériser les propriétés semi-conductrices de ces nanoparticules et d'observer certains comportements inhabituels. De plus, l'analyse combinée des données de photoélectrochimie et de photocatalyse a permis d'élucider le fonctionnement de cet assemblage nanoparticules-liant. Il apparaît que la paire électron-trou se crée dans la nanoparticule semi-conductrice, que le liant permet l'évacuation de l'électron par un positionnement de ses bandes d'énergie adéquat et que l'ensemble peut être contrôler pour produire les vitrages auto-nettoyants à base de nanoparticules de TiO2 les plus performantsNowaday, the building market is looking for new materials, especially glasses with self-cleaning properties which do not need much maintenance. Photoreactive surfaces containing titaniµm dioxide nanoparticles seem to be very well suited to this application. In fact, under an UV radiation, these surfaces are able to degrade, by mean of a photocatalytic process, a wide range of organic residues. This work consists in the photoelectrochemical characterisation of thoses photoreactive surfaces made with TiO2 nanoparticles and a binder. By photoelectrochemistry, it was possible to characterized the semi-conductìng properties of thoses nanoparticles and to observe an unusual behavior. The analysis of all the datas issues of photoelectrochemícal and photocatalytical experiments allowed to elucidate a mechanism involving a co-operation between the nanoparticles and the binder. The electron-hole pair is created in the nanoparticle and the binder supports the evacuation of the electron by an adequate band energy level. Acting on the nanoparticles-binder system, it could be possible to obtain the best performing self-cleaning glasses
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De, La Fuente Garcia Elena Luisa. „Visible Light Photocatalyst for Water Purification and Self-Cleaning Coatings“. Doctoral thesis, Università degli studi di Bergamo, 2018. http://hdl.handle.net/10446/108456.
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Pollution in water and atmosphere is a growing concern in the current society and demands short-term solutions. Conventional purification techniques like biological treatment, direct oxidation, etc. cannot eliminate low concentrations or some of the so-called emerging pollutants (hormones, detergents, pharmaceuticals, etc.) thus calling for the use of advanced oxidation processes (AOP), namely, techniques in which highly oxidising agents (mostly OH radicals) are produced to degrade organics compound, bacteria and viruses, reaching the complete mineralization or, at least, producing nontoxic by-products. One of these techniques is heterogeneous photocatalysis: redox reactions are developed on the surface of a solid catalyst that is activated by light. Nowadays the more employed and studied photocatalyst is titanium dioxide (TiO2). Its commercial applications are very diverse, including self-cleaning materials (cements, paints), antifogging materials (mirrors, glasses) and water and air purification devices. The operating limits of this effective photocatalyst are in the fact that it needs UV radiation to be activated, due to its relatively wide band gap (3.2 eV). This is a significant problem in economic terms, for high energy costs, in healthy terms, since UV radiation is dangerous for sight and skin, and it is a limit to the use of sunlight, as only 4 % of the solar spectrum that reaches the Earth surface is in the UV range. To overcome this problem, investigations are focused on TiO2 modifications to render it active with visible light (doping with metal and non-metal ions, coupling with other semiconductors, etc) as well as on the use of other semiconductors with narrower band gap.
A ceramic material, lanthanum orthoferrite (LaFeO3), with ionic and electronic semiconductor properties, is synthesized in our laboratory since 2008 and it is studied for its application in the combustion cells. Knowing that it also works as photoconductor under visible light [3], it can be considered a good candidate to be used as visible light photocatalyst. Its effectiveness in the degradation of organic dyes and other molecules has been reported.
After the successful degradation of organic compounds in the slurry tests carried up with the LaFeO3 powders, our group started to develop deposition systems in order to avoid filtration problems, such as loss of catalyst and costs, thus rendering the reuse of the photocatalyst easier to achieve a practical applicability. In the present thesis two deposition methods were studied: the preparation of a photocatalytic paint and the deposition of the catalyst over a ceramic foam by dip-coating process.
In the first part of the work, LaFeO3 was added to a commercial water based paint. This innovative photocatalytic paint has been tested to prove two aspects:
• Its self-cleaning performances, following the degradation of an azo dye under visible light irradiation.
• The paint durability, executing accelerated ageing tests in a climatic chamber, and subsequently verifying visible alterations and possible diminution of its self-cleaning performances.
In the second part, the objective was the application of the material for the wastewater treatment. In collaboration with the Universidad de Las Palmas de Gran Canaria a handy and resistant photocatalytic foam was developed, to avoid the vigorous continuous stirring required to keep powder in slurry and the necessary filtration after the reactions to reuse the photocatalyst. The support chosen was a commercial ceramic inert porous material (foam) and the deposition method was the dip-coating technique.
To apply this coating technique high quantities of catalyst had to be used because it required the preparation of a very concentrate solution. For this reason and for a possible scaling up, the production rate of the photocatalyst in our laboratory had to be increased. The quality of the catalyst had been largely tested for low production rates. Theoretically the results of the synthesis must be the same; however, a complete characterization and determination of photocatalytic performances were carried out on three batches of catalyst prepared on a large scale.
The photocatalytic foam and the different batches in slurry were tested in the degradation of 4-Nitrophenol. A comparison between the slurry test and the fixed bed test is presented.
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Králová, Marcela. „Samočistící vlastnosti tenkých tištěných vrstev oxidu titaničitého“. Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-233352.
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Tenké vrstvy oxidu titaničitého byly imobilizovány na sodnovápenatá skla a skelný uhlík použitím jak techniky materiálového tisku tak metodou chemického napařování. Pro přípravu titaničitých solů byly použity metody sol-gelu a nebo hydrotermální syntézy. Struktura připravených vrstev byla zkoumána rastrovací elektronovou mikroskopií a mikroskopií atomárních sil. Krystalická struktura připravených TiO2 byla analyzovány pomocí XRD metody. Fotoindukováná superhidrofility pripravených vzorků byla charakterizována měřením kontaktních úhlů. Fotokatalytická aktivity připravených vzorků byla testována na fotokatalytické oxidaci 2,6-dichlorindofenolu a kyseliny mravenčí. V případě sol-gel vrstev byl zkoumán vliv množství naneseného TiO2 a množství PEG, který byl do solu přidán jako praskliny potlačující činidlo. V případě hydrotermálních vrstev byl zkoumán vliv času a teploty syntézy a množství vrstev na výslednou účinnost vzorku. U chemicky napařených vzorků byl zjišťován vliv intenzity záření. Byla porovnána fotokatalitická aktivita vrstev připravených materiálovým tiskem a chemickým napařováním a byl vyhodnocen nejaktivnější vzorek.
Buchteile zum Thema "Photocatalysis Self-Cleaning"
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Ramirez, Anibal Maury, und Nele De Belie. „Application of TiO2 Photocatalysis to Cementitious Materials for Self-Cleaning Purposes“. In Applications of Titanium Dioxide Photocatalysis to Construction Materials, 11–15. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-1297-3_3.
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Saeki, Yoshimitsu. „Application of Antibacterial and Self-Cleaning Effects to Noncementitious Construction Materials“. In Applications of Titanium Dioxide Photocatalysis to Construction Materials, 17–22. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-1297-3_4.
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Kamegawa, Takashi, und Hiromi Yamashita. „Chapter 4. Superhydrophilic and Superhydrophobic Thin Film Type of Photocatalysts with Self-cleaning Properties“. In Self-cleaning Coatings, 86–104. Cambridge: Royal Society of Chemistry, 2016. http://dx.doi.org/10.1039/9781782623991-00086.
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Ong, Jun Hui, Guangxu Yan, Niroj Maharjan und Zhong Chen. „Development of Photocatalytic Self-cleaning 316 Stainless Steel Surface“. In Lecture Notes in Mechanical Engineering, 423–34. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-8643-9_49.
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Benny, Geethu, und Gayathri Krishna Kumar. „Experimental Study of Self-cleaning Concrete by Using Various Photocatalysts“. In Lecture Notes in Civil Engineering, 241–49. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-55115-5_23.
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Thakur, Naveen, S. B. Singh und Anshuman. „Use of Photocatalyst in Self-Cleaning Constructions Material: A Review“. In Advances in Sustainable Materials and Resilient Infrastructure, 117–32. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-9744-9_8.
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Saini, Anil, und Jatinder Kumar Ratan. „A Review on Titanium Dioxide Based Photocatalytic Cement: Self-cleaning Cement“. In Advances in Chemical, Bio and Environmental Engineering, 239–73. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-96554-9_18.
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Storozhenko, D., O. Dryuchko, T. Jesionowski und I. Ivanytska. „Some Physicochemical Aspects of the Preparatory Stages in the Formation of Self-cleaning Photocatalytic Active Coatings for Building Construction Materials“. In Lecture Notes in Civil Engineering, 285–301. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-42939-3_30.
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Punnoli Ammed, Saeed, Anupama R. Prasad und Sanjay Gopal Ullattil. „Chapter 5 Self-Cleaning Surfaces: Experimental Advances and Surface Model Controversies“. In Photocatalysis, 135–62. De Gruyter, 2021. http://dx.doi.org/10.1515/9783110668483-005.
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Panwar, Kamlesh, Neelam Vyas, Roopali Rai und Shreedhar Bhat. „Self-Cleaning Surfaces of Polyurethanes“. In Nature-Inspired Self-Cleaning Surfaces in Nanotechnology Era [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.111929.
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In this urbanized world, people have limited time and access to labors to clean the items one is associated with. Self-cleaning of the items which humans use every day or occasional is more sustainable for long term and is also one of the most important functionalities for improved esthetics, performance, hygiene, and satisfaction. Various approaches have been widely explored to impart self-cleaning properties to different substrates using different chemistries of surface modifications. The current chapter gives an overview of the various mechanisms for self-cleaning including super-hydrophobicity, super-hydrophilicity and photocatalysis with more emphasis on polyurethane origin. Polyurethanes have been widely explored for self-cleaning properties by introducing super-hydrophobicity via incorporation of nano-roughness or low energy functionalities or by introducing photocatalytic property by incorporating photocatalytic nanoparticles. The chapter also provides a connect to the applications of such polyurethane surfaces. Thus, these self-cleaning polyurethanes may find applications in the fields of anti-fogging, anti-icing, anti-reflection, corrosion resistance, drag reduction, sensors, solar cells, and textiles.
Konferenzberichte zum Thema "Photocatalysis Self-Cleaning"
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Rasponi, Marco, Tania Ullah, Richard Gilbert, Gianfranco B. Fiore und Todd Thorsen. „A Microfluidic Device for Flow-Through Blood Oxygenation by Photocatalytic Action“. In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206652.
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The breakthrough work of Fujishima and Honda in 1972 [1], in which they achieved ultraviolet light-induced water cleavage with the use of titanium dioxide (TiO2) in an electrochemical cell, has drawn considerable attention in recent years to the “acceleration of a photoreaction by the presence of a catalyst” [2] or photocatalysis. Research on photocatalysis has explored the decomposition of organic pollutants and microorganisms, the superhydrophilic self-cleaning properties of surfaces, and the photosplitting of water, among other applications. Semiconductors can act as photocatalysts because of their electronic structure and TiO2, in particular, has been a popular choice. It is non-toxic and mechanically stable, can be fabricated at low-cost, and the anatase phase of TiO2 has a bandgap of approximately 3.2 eV, ideal for excitation by light in the ultraviolet range.
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Tota-Maharaj, Kiran, und Nichola Coleman. „Developing Novel Photocatalytic Cementitious Permeable Pavements for Depollution of Contaminants and Impurities in Urban Cities“. In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.053.
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Photocatalyst such as Titanium Dioxide (TiO2) has been recently introduced as a nanoparticle into cementitious permeable pavements. Combining photocatalytic compounds within concrete permeable pavements can aid with depollution of several contaminants found in urban water streams and air impurities. This paper presents research carried out at the University of Greenwich, UK using photocatalytic concrete with varying percentages of TiO2 (0 %, 1% and 5%) to assess the levels depollution which can be achieved. Concrete samples were testing against the degradation of 2, 4-Dichlorophenoxyacetic Acid, a harmful chemical found in herbicides. This advanced oxidation process can aid in the reduction of urban pollution from an air and water perspective, improving sustainability for urban cities. Self-cleaning benefits of photocatalytic concrete permeable pavements can be used to keep urban infrastructure cleaner and more aesthetically pleasing. Experimental tests were carried out on the characterisation of inorganics through X-Ray diffraction and Fourier Transform Infrared Spectroscopy to ensure that the structures of the concrete samples were not altered by addition of the nanoparticles (photocatalyst). Experimental results were compared to that found in previous literature and confirmed that the addition of 5% TiO2 did not affect the structure of the concrete samples and can be a viable option used in urban infrastructure such as permeable pavements.
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FUJISHIMA, AKIRA. „PHOTOCATALYTIC AND SELF-CLEANING FUNCTIONS OF TiO2 COATINGS“. In Proceedings of the Third Asia-Pacific Conference. WORLD SCIENTIFIC, 2000. http://dx.doi.org/10.1142/9789812791924_0001.
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BÍBOVÁ, Hana, Jan ŠUBRT, Eva PLIŽINGROVÁ, Michaela JAKUBÍČKOVÁ, Tereza SÁZAVSKÁ, Pavel DOHNÁLEK, Lenka HYKRDOVÁ und Jaromír JIRKOVSKÝ. „PHOTOCATALYTIC CONCRETE SCREEDS WITH SELF-CLEANING AND ANTIMICROBIAL FUNCTION“. In NANOCON 2019. TANGER Ltd., 2020. http://dx.doi.org/10.37904/nanocon.2019.8515.
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MASAR, Milan, Hassan ALI, Muhammad YASIR, Jakub SEVCIK, Michal URBANEK, Tomas SOPIK, Michal MACHOVSKY und Ivo KURITKA. „ZnO/Cu2O heterojunctions treated glass surface for photocatalytic and self-cleaning applications“. In NANOCON 2022. TANGER Ltd., 2022. http://dx.doi.org/10.37904/nanocon.2022.4598.
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Nakagawa, Hirotoshi, Kouhei Mathuoka und Hironobu Yonemori. „A study about the self-cleaning of a PV module surface using photocatalyst“. In 2014 IEEE Region 10 Humanitarian Technology Conference (R10-HTC). IEEE, 2014. http://dx.doi.org/10.1109/r10-htc.2014.7026325.
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Hawkins, A., D. Guo, A. Steeves, F. Variola und B. Jodoin. „Production of Titanium Dioxide with Optimum Heterojunctions and Coating Production via Cold Spray“. In ITSC2022. DVS Media GmbH, 2022. http://dx.doi.org/10.31399/asm.cp.itsc2022p0483.
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Abstract Titanium dioxide (TiO2) coatings possess high appeal due to self-cleaning properties that can accelerate decomposition of organic pollutants. The global objective is to develop a cold sprayable feedstock powder with an outer titanium dioxide shell that maximises anatase-rutile heterojunctions for enhanced photocatalytic activity under ultraviolet light and the development of cold spray process parameters for successful deposition of this powder into thin photocatalytic coatings. The objective of this reported first step of our global research effort to produce superior photocatalytic TiO2 coatings by cold spray is to successfully engineer anatase and rutile nanostructure heterojunction shells on pure titanium (CP-Ti) powder known to be easily sprayable by cold spray and then verify its photocatalytic properties through exposure to an organic pollutant, methylene blue (MB). Anatase and rutile heterojunctions are desired due to high activity, stability and broadened bandwidth as opposed to each singular nanostructure. The resulting powder coming out of this first step was characterized using Raman spectroscopy to verify the presence of the desired heterojunctions. The photocatalytic reactivity was tested and evaluated through the degradation of methylene blue upon contact with the TiO2 powder. Results of this first step showed growth of desired heterojunctions and high reactivity of the produced powder.
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Chirila, Laura, Marcela Corina Rosu, Sabina Olaru, Cristian Tudoran, Dragos-Viorel Cosma, Alexandra Urda, Alice-Ortansa Mateescu, Gheorghe Mateescu und 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.
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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.
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Lu, Y. S., Y. C. Lin, L. W. Lai, S. C. Hong und D. S. Liu. „Packaging organic Light Emitting Diode with surface self-cleaning using a highly active amorphous titanium oxide photocatalytic thin film“. In 2012 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2012. http://dx.doi.org/10.7567/ssdm.2012.ps-8-8.
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Motohashi, K. „Performance Evaluation of Self-Cleaning Effect for Photocatalyst-Applied Exterior Finishing Materials through Outdoor Exposure Test and Laboratory Test“. In RILEM International Symposium on Environment-Conscious Materials and Systems for Sustainable Development. RILEM Publications SARL, 2005. http://dx.doi.org/10.1617/2912143640.003.
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