Visible Light-Responsive N-Doped TiO2 Photocatalysis: Synthesis, Characterizations, and Applications

Abstract

Photocatalysis based on semiconductors has recently been receiving considerable research interest because of its extensive applications in environmental remediation and renewable energy generation. Various semiconductor-based materials that are vital to solar energy utilization have been extensively investigated, among which titanium oxide (TiO2) has attracted considerable attention because of its exceptional physicochemical characteristics. However, the sluggish responsiveness to visible light in the solar spectrum and the inefficient separation of photoinduced electron–hole pairs hamper the practical application of TiO2 materials. To overcome the aforementioned serious drawbacks of TiO2, numerous strategies, such as doping with foreign atoms, particularly nitrogen (N), have been improved in the past few decades. This review aims to provide a comprehensive update and description of the recent developments of N-doped TiO2 materials for visible light-responsive photocatalysis, such as (1) the preparation of N-doped/co-doped TiO2 photocatalysts and (2) mechanistic studies on the reasons for visible light response. Furthermore, the most recent and significant advances in the field of solar energy applications of modified N-doped TiO2 are summarized. The analysis indicated the critical need for further development of these types of materials for the solar-to-energy conversion, particularly for water splitting purposes.

Bio-Inspired C/N/TiO2 Hybrid Composite Heterostructure: Enhanced Photocatalytic Activity under Visible Light

“…e photocatalytic mechanism of bio-inspired C/N/TiO 2 hybrid composite heterostructure is a result of the combined effects of the light-induced charge separation at the semiconductor/oxide interface and the electron-transfer reactions between the catalyst and the substrate. In addition, photogenerated electrons and holes can be absorbed by adsorbed oxygen molecules and surface hydroxyl, respectively, both of which result in the creation of highly oxidative hydroxyl radical species (•OH) [12]. Because of their great oxidative capacity, (•OH) molecules attack dye molecules with minimal selectivity and are able to oxidize contaminants because of their high oxidative potential.…”

“…Despite the fact that other photo-catalyst candidates have been investigated, titanium dioxide (TiO 2 ) has been the most thoroughly investigated material, and it is now considered to be the most likely photocatalyst for industrial-scale applications due to its high photoactivity e ciency, long-term stability, nontoxicity, and low price [7][8][9][10][11]. Recent research on the use of TiO 2 as a photocatalyst has concentrated on enhancing the material's photocatalytic activity under visible light and increasing its speci c surface area [12]. is is being done in an e ort to boost the e ciency with which solar energy is converted while simultaneously bringing down the associated costs.…”

“…In the case of metal ion doping, the photocatalytic activity failed due to insu cient interfacial electron transfer rates and charge carrier recombination rates, which resulted in poor photocatalytic activity [19,22,23]. On the other hand, nonmetal anion doping often increases the specific surface area of TiO 2 photocatalysts, limits the growth of crystallite size, and increases the percentage of anatase phase in the photocatalyst [12,19,24,25]. Additionally, nonmetal anions (C/N/ P/S, etc.)…”

Porous Copper Foam‐Based Plasmonic Nanocrystals Modified 3D Semiconductor Nanoflowers for Multifold, Recyclable, and Portable Detection of Environmental Contaminant

“…However, the narrow spectral response range and high carrier recombination rate of TiO 2 severely limit its practical application. [13][14][15] Compared with the powder catalysts with low specific surface area and easy to agglomerate, 1D TiO 2 array can be used as the supported matrix since it possesses uniform nanostructure, [16,17] good recycla bility, large specific surface area, [18] and broaden adsorption ability. [19][20][21] Besides, constructing specific nanoarchitectures such as 1D nanostructures and their 3D arrays, which can effec tively restrain the recombination of charge carriers through shortening the diffusion length of minority carrier to the TiO 2 surface, [22][23][24] has been demonstrated to be a valid approach to design competitive photocatalytic systems.…”

Synthesis of Ag decorated TiO2 nanoneedles for photocatalytic degradation of methylene blue dye

“…Among these applications, TiO 2 has the most promising application in the field of photocatalysts due to its excellent photoactivity, non-toxicity, high stability, water-insoluble properties under most conditions and low cost [36]. Efforts are devoted to the production of effective TiO 2 photocatalysis-based water and air purification technologies [37]. Usually, using this treatment the nonpoisonous inorganic materials could be obtained by oxidizing the poisonous organic composites [38,39].…”