Recent Advances in Synthesis and Applications of Carbon-Doped TiO2 Nanomaterials

Abstract

TiO2 has been widely used as a photocatalyst and an electrode material toward the photodegradation of organic pollutants and electrochemical applications, respectively. However, the properties of TiO2 are not enough up to meet practical needs because of its intrinsic disadvantages such as a wide bandgap and low conductivity. Incorporation of carbon into the TiO2 lattice is a promising tool to overcome these limitations because carbon has metal-like conductivity, high separation efficiency of photogenerated electron/hole pairs, and strong visible-light absorption. This review would describe and discuss a variety of strategies to develop carbon-doped TiO2 with enhanced photoelectrochemical performances in environmental, energy, and catalytic fields. Emphasis is given to highlight current techniques and recent progress in C-doped TiO2-based materials. Meanwhile, how to tackle the challenges we are currently facing is also discussed. This understanding will allow the process to continue to evolve and provide facile and feasible techniques for the design and development of carbon-doped TiO2 materials.

Photocatalysis over N-Doped TiO2 Driven by Visible Light for Pb(II) Removal from Aqueous Media

“…With respect to the photocatalysis process, TiO 2 as a photocatalyst has recently received considerable attention for the removal of persistent organic pollutants (POPs), including phenols [11], tetracycline [12], dyes [13] and linier alkyl benzene sulphonate [14] due to its cost-effective technology, non-toxicity, quick oxidation rate and chemical stability [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. The practical application of TiO 2 is, however, significantly restricted by its low visible absorption due to its wide bandgap energy (Eg) ≈ 3.20 eV [15][16][17][18][19][20][21][22][23][24][25][26] and immediate charge (electron and hole) recombination [19][20][21][22]. With such wide a band gap, TiO 2 can only be excited by photons with wavelengths shorter than 385 nm emerging in UV region [15][16][17][18][19][20][21][22]…”

“…The practical application of TiO 2 is, however, significantly restricted by its low visible absorption due to its wide bandgap energy (Eg) ≈ 3.20 eV [15][16][17][18][19][20][21][22][23][24][25][26] and immediate charge (electron and hole) recombination [19][20][21][22]. With such wide a band gap, TiO 2 can only be excited by photons with wavelengths shorter than 385 nm emerging in UV region [15][16][17][18][19][20][21][22][23][24][25][26]. In fact, UV light only occupies a small portion (about 5%) of the sunlight spectrum [15,[19][20][21]23,24], which limits TiO 2 application under low-cost sunlight or visible irradiation.…”

Development of activated carbon-doped TiO2 nanoparticle thin film for application in dye-sensitized solar cells

“…This may be due to broader absorbance range [22]. Moreover, TiO2 doping with activated carbon also can help to narrow band gap energy and facilitate the separation of photogenerated charge carriers, resulting in its enhanced efficiency [23][24][25][26].…”

Editorial Catalysts: Special Issue on Recent Advances in TiO2 Photocatalysts

“…However, due to the large energy band gap, its activity in the range of natural solar light is quite limited. For this reason, the development of new TiO 2 -based photocatalysts active in the visible range has become a new research trend [1,3,6,13,[15][16][17][18][19]. The effectivity can also be improved by modifying TiO 2 with noble metals [2,13,15] or by Ti 3+ -self-doped TiO 2 modification [11].…”

“…The high potential of TiO 2 -GQD nanocomposites has been shown in the context of the photocatalytic degradation of micropollutants, H 2 production from water splitting, and dye-sensitized solar cells, as well as biomedical applications including drug delivery, biosensing, tissue engineering, and applications as contrasting agents in bioimaging [9]. Assessing improvements in photoelectrochemical performance in environmental, energy, and catalytic applications of carbon-doped TiO 2 was the main goal of Hua and co-workers' review paper [17]. Herein, the synthesis methods, as well as surface characteristics of C-doped TiO 2 -based materials, were presented.…”