Photocatalysis

About: Photocatalysis is a research topic. Over the lifetime, 67088 publications have been published within this topic receiving 2145233 citations. The topic is also known as: photocatalyst.

Photocatalytic Activity Improvement and Application of UV-TiO2 Photocatalysis in Textile Wastewater Treatment: A Review

Abstract: Treatment of textile wastewater using titanium dioxide (TiO2) photocatalysis has been started from the last decade and reached attention to the researchers because of its versatile application. The variety of applications of TiO2 as a photocatalyst has been taken place because of low operating temperature, biologically inert nature, low energy consumption, water insolubility, ease availability and photoactivity, less toxicity, high chemical stability, suitable flat band potential, narrow band gap and environmentally benign. The successful and efficient application of photocatalysis depends on quality of photocatalyst, nature of pollutants, and source of light, which should be in close contact with each other. The TiO2 photocatalyst is used for the effluent treatment of textile wastewater in the presence of ultraviolet (UV) irradiation. Heterogeneous UV-TiO2 photocatalysis is capable to remove organic pollutants from textile wastewater, which has been widely studied and the technology also being commercialized in many developing countries in the world. This review focuses on the mechanism of UV-TiO2 photocatalysis, modification of TiO2 photocatalyst, and application of doping and co-doping in order to improve the photocatalytic activity in wastewater treatment. In addition, the review conveys comprehensive and fundamental assessments of the photocatalytic activity for the removal of organic dyes and phenolic compounds from textile wastewater.

Relationship between photocatalytic activity, hydrophilicity and self-cleaning effect of TiO2/SiO2 films

Abstract: Self-cleaning glass can be realized utilizing photo-induced hydrophilicity of titanium dioxide. In order to understand the photo-induced hydrophilic self-cleaning effect, it is necessary to understand the relationship between the mutual effect of photohydrophlicity and photocatalysis. In this paper, the relationship between hydrophilicity, photocatalysis and the self-cleaning effect is investigated. It is found that the TiO2/SiO2 surface can have more hydrophilic activity and less photocatalytic activity, or vice versa by adding different amount of SiO2. It is the synergetic effect of hydrophilicity and photocatalysis that improves and maintains the self-cleaning effect. SiO2 addition increases the acidity which results in the increase of the hydroxyl content in the composite films, with the consequence that the hydrophilicity and photocatalytic activity are increased during UV irradiation thus enhances the self-cleaning effect.

Dramatic visible photocatalytic degradation performances due to synergetic effect of TiO2 with PANI.

Abstract: The dramatic visible light photocatalytic activity was obtained for the degradation of Methylene Blue (MB) and Rhodamine B (RhB) under visible light irradiation (λ > 450 nm) after TiO2 photocatalysts were modified with monolayer dispersed polyaniline (PANI ) via a facile chemisorption approach. Under visible light irradiation, PANI generated π−π* transition, delivering the excited electrons into the conduction band of TiO2, and then the electrons transferred to an adsorbed electron acceptor to yield oxygenous radicals to degrade pollutants. Also, the ultraviolet photocatalytic performance was enhanced to about two times compared with that of P-25 TiO2 photocatalyst. The high photocatalytic activity came from the synergetic effect between PANI and TiO2, which promoted the migration efficiency of photogenerated carriers on the interface of PANI and TiO2. Under ultraviolet light irradiation, photoinduced holes in TiO2 valence band could transfer into HOMO orbital of PANI and then emigrate to the photocatalys...

Recent advances in photocatalysis for environmental applications

Abstract: Advanced Oxidation technologies (AOTs) are gaining attention as an effective waste water treatment methodology capable of degrading diverse spectrum of recalcitrant organic contaminants and microbes. Undoubtedly, photocatalysis is a promising AOT to alleviate the problem of water pollution. Despite recent research into other photocatalysts (e.g. ZnO, ZnS, Semiconductor-Graphene composites, perovskites, MoS2, WO3 and Fe2O3), titanium dioxide (TiO2) remains the most popular photocatalyst due to its low cost, nontoxicity and high oxidising ability. Moreover, titania photocatalysts can easily be immobilized on various surfaces and be scaled up for large scale water treatment. The current review aims to highlight recent advancements in photocatalytic AOTs with main emphasis on TiO2 photocatalysis. This review also discusses the use of TiO2 photocatalysis for water and waste treatment, treating contaminants of emerging concern (CECs), pesticides, endocrine disrupters (EDs) and bacteria using both UV and visible light irradiations. It was concluded that with efficient photoreactor configuration and further studies on the photocatalyst regeneration, TiO2 photocatalysis is a viable option for the reclamation of agricultural/irrigational waste water. Novel doped photocatalysts such as ZnS-CuS-CdS, carbon spheres/CdS, g-C3N4-Au-CdS, ZnS-WS2-CdS, C3N4-CdS and Pd-Cr2O3-CdS have also been discussed. Finally, the advances in the actively studied metal organic framework based photocatalysts that are emerging as effective alternate for metal oxide based photocatalysts is also discussed in detail.