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

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.

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Titanium Dioxide: From Engineering to Applications

Catalysts ◽

10.3390/catal9020191 ◽

2019 ◽

Vol 9 (2) ◽

pp. 191 ◽

Cited By ~ 62

Author(s):

Xiaolan Kang ◽

Sihang Liu ◽

Zideng Dai ◽

Yunping He ◽

Xuezhi Song ◽

...

Keyword(s):

Titanium Dioxide ◽

Visible Light ◽

Photocatalytic Performance ◽

Environmental Pollutants ◽

Photogenerated Electron ◽

Wide Bandgap ◽

Electron Hole ◽

Crystal Facet ◽

Tio2 Lattice ◽

Tio2 Nanomaterials

Titanium dioxide (TiO2) nanomaterials have garnered extensive scientific interest since 1972 and have been widely used in many areas, such as sustainable energy generation and the removal of environmental pollutants. Although TiO2 possesses the desired performance in utilizing ultraviolet light, its overall solar activity is still very limited because of a wide bandgap (3.0–3.2 eV) that cannot make use of visible light or light of longer wavelength. This phenomenon is a deficiency for TiO2 with respect to its potential application in visible light photocatalysis and photoelectrochemical devices, as well as photovoltaics and sensors. The high overpotential, sluggish migration, and rapid recombination of photogenerated electron/hole pairs are crucial factors that restrict further application of TiO2. Recently, a broad range of research efforts has been devoted to enhancing the optical and electrical properties of TiO2, resulting in improved photocatalytic activity. This review mainly outlines state-of-the-art modification strategies in optimizing the photocatalytic performance of TiO2, including the introduction of intrinsic defects and foreign species into the TiO2 lattice, morphology and crystal facet control, and the development of unique mesocrystal structures. The band structures, electronic properties, and chemical features of the modified TiO2 nanomaterials are clarified in detail along with details regarding their photocatalytic performance and various applications.

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Construction of Ag3PO4/SnO2 Heterojunction on Carbon Cloth with Enhanced Visible Light Photocatalytic Degradation

Applied Sciences ◽

10.3390/app10093238 ◽

2020 ◽

Vol 10 (9) ◽

pp. 3238

Author(s):

Min Liu ◽

Guangxin Wang ◽

Panpan Xu ◽

Yanfeng Zhu ◽

Wuhui Li

Keyword(s):

Visible Light ◽

Photocatalytic Performance ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Carbon Cloth ◽

Electron Hole ◽

Step Process ◽

Photogenerated Electrons ◽

Rapid Transfer ◽

Visible Light Photocatalytic

In this study, the Ag3PO4/SnO2 heterojunction on carbon cloth (Ag3PO4/SnO2/CC) was successfully fabricated via a facile two-step process. The results showed that the Ag3PO4/SnO2/CC heterojunction exhibited a remarkable photocatalytic performance for the degradation of Rhodamine B (RhB) and methylene blue (MB), under visible light irradiation. The calculated k values for the degradation of RhB and MB over Ag3PO4/SnO2/CC are 0.04716 min−1 and 0.04916 min−1, which are higher than those calculated for the reactions over Ag3PO4/SnO2, Ag3PO4/CC and SnO2/CC, respectively. The enhanced photocatalytic activity could mainly be attributed to the improved separation efficiency of photogenerated electron-hole pairs, after the formation of the Ag3PO4/SnO2/CC heterojunction. Moreover, carbon cloth with a large specific surface area and excellent conductivity was used as the substrate, which helped to increase the contact area of dye solution with photocatalysts and the rapid transfer of photogenerated electrons. Notably, when compared with the powder catalyst, the catalysts supported on carbon cloth are easier to quickly recycle from the pollutant solution, thereby reducing the probability of recontamination.

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Fabrication, characterization and photocatalytic activity of g-C3N4 coupled with FeVO4 nanorods

RSC Advances ◽

10.1039/c5ra01484k ◽

2015 ◽

Vol 5 (35) ◽

pp. 27933-27939 ◽

Cited By ~ 28

Author(s):

Qingyan Nong ◽

Min Cui ◽

Hongjun Lin ◽

Leihong Zhao ◽

Yiming He

Keyword(s):

Photocatalytic Activity ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Electron Hole

The coupling of FeVO4 nanorods with g-C3N4 promotes the separation efficiency of photogenerated electron–hole pairs, and subsequently enhances its photocatalytic activity in rhodamine photodegradation.

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Synthesis of Er-doped Bi2WO6 and enhancement in photocatalytic activity induced by visible light

RSC Advances ◽

10.1039/c5ra19164e ◽

2015 ◽

Vol 5 (115) ◽

pp. 94887-94894 ◽

Cited By ~ 25

Author(s):

Meng Wang ◽

Ziyu Qiao ◽

Minghao Fang ◽

Zhaohui Huang ◽

Yan'gai Liu ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Electron Hole ◽

Er Doped

1.5% Bi2WO6:Er3+ exhibited highest photocatalytic activity as the separation efficiency of the photogenerated electron–hole pairs is enhanced.

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Ag3PO4 Deposited on CuBi2O4 to Construct Z-Scheme Photocatalyst with Excellent Visible-Light Catalytic Performance Toward the Degradation of Diclofenac Sodium

Nanomaterials ◽

10.3390/nano9070959 ◽

2019 ◽

Vol 9 (7) ◽

pp. 959 ◽

Cited By ~ 7

Author(s):

Xiaojuan Chen ◽

Chunmu Yu ◽

Runliang Zhu ◽

Ning Li ◽

Jieming Chen ◽

...

Keyword(s):

Degradation Rate ◽

Performance Enhancement ◽

Separation Efficiency ◽

Diclofenac Sodium ◽

Sodium Stearate ◽

Photogenerated Electron ◽

Catalytic Performance ◽

Electron Hole ◽

In Situ Deposition

CuBi2O4/Ag3PO4 was synthesized through a combination of hydrothermal synthesis and an in situ deposition method with sodium stearate as additives, and their textures were characterized with XRD, XPS, SEM/HRTEM, EDS, UV-Vis, and PL. Then, the photodegradation performance of CuBi2O4/Ag3PO4 toward the degradation of diclofenac sodium (DS) was investigated, and the results indicate that the degradation rate of DS in a CuBi2O4/Ag3PO4 (1:1) system is 0.0143 min−1, which is 3.6 times that in the blank irradiation system. Finally, the photocatalytic mechanism of CuBi2O4/Ag3PO4 was discussed, which follows the Z-Scheme theory, and the performance enhancement of CuBi2O4/Ag3PO4 was attributed to the improved separation efficiency of photogenerated electron–hole pairs.

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Tunable Synthesis of Ultrathin BiOCl 2D Nanosheets for Efficient Photocatalytic Degradation of Carbamazepine upon Visible-Light Irradiation

Journal of Chemistry ◽

10.1155/2020/1950645 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Shuo Xu ◽

Xiaoya Gao ◽

Wenfeng Xu ◽

Pengfei Jin ◽

Yongmei Kuang

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Light Irradiation ◽

Electron Hole ◽

Magnetic Stirring ◽

Degradation Activity

A series of ultrathin BiOCl 2D nanosheet photocatalysts were prepared by the TBAOH-assisted hydrolysis method in water. The effects of tetrabutylammonium hydroxide (TBAOH) dosages, chlorine source, preparation pH value, ultrasonic treatment, and magnetic stirring on the photocatalytic degradation dynamics of carbamazepine were examined under visible-light irradiation to optimize the preparation parameters. It was found that ultrathin BiOCl prepared with TBAOH dosages of 1 mmol and chlorine source of NaCl in the pH of 2 upon magnetic stirring of 6 h displayed the highest photocatalytic degradation rate constant (0.0038 min−1) of carbamazepine, which is 7.6 times higher than that with the ordinary BiOCl (without TBAOH). To clarify the mechanism on the outstanding photocatalytic activity of ultrathin BiOCl, the elemental composition/state, micromorphology, and separation efficiency of photogenerated electron-hole pairs were investigated by X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and photoluminescence (PL). Results showed that the presence of oxygen vacancy, ultrathin nanosheet structure, and improved separation efficiency of photogenerated electron-hole pairs contributed to the excellent photocatalytic degradation activity of ultrathin BiOCl. The obtained result provides a novel method to fabricate ultrathin BiOCl with excellent photocatalytic degradation activity of carbamazepine under visible-light irradiation.

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Synthesis and Characterization of Amorphous Molybdenum Sulfide (MoSx)/CdIn2S4 Composite Photocatalyst: Co-Catalyst Using in the Hydrogen Evolution Reaction

Catalysts ◽

10.3390/catal10121455 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1455

Author(s):

Qi Li ◽

Wanli Liu ◽

Xuejian Xie ◽

Xianglong Yang ◽

Xiufang Chen ◽

...

Keyword(s):

Hydrogen Production ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Molybdenum Sulfide ◽

Electron Hole ◽

Composite Photocatalyst ◽

Co Catalyst ◽

Pair Separation ◽

Electron Hole Pair

Co-catalyst deposition is used to improve the surface and electrical properties of photocatalysts. In this work, MoSx/CdIn2S4 nanocomposites were prepared by a facile hydrothermal and photodeposition route. The basic crystalline phases and morphology of the as-prepared samples were determined, and these results showed that MoSx was tightly anchored onto CdIn2S4 by sharing the same S atom. In the hydrogen production experiments, MoSx/CdIn2S4-40 displayed the optimal photocatalytic hydrogen production yield in 4 h. The H2 evolution rate reached 2846.73 μmol/g/h, which was 13.6-times higher than that of pure CdIn2S4. Analyzing the photocatalytic enhancement mechanisms revealed that this unique structure had a remarkable photogenerated electron-hole pair separation efficiency, rapid charge carrier transfer channels, and more abundant surface reaction sites. The use of co-catalyst (MoSx) greatly improved the photocatalytic activity of CdIn2S4.

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Synthesis and High Visible Light Photocatalytic Activity of Ternary Brookite-g-C3N4-BiOBr Composite

NANO ◽

10.1142/s1793292020500459 ◽

2020 ◽

Vol 15 (04) ◽

pp. 2050045

Author(s):

Ning Liu ◽

Huidong Xie ◽

Jie Li ◽

Yajuan Zhao ◽

Na Wang

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Rhodamine B ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Photocurrent Density ◽

Electron Hole ◽

Degradation Ratio ◽

Loading Amount ◽

Visible Light Photocatalytic

Brookite TiO2 was synthesized by a hydrothermal method, g-C3N4 was prepared by a pyrolytic method, brookite/g-C3N4 composites were prepared by a calcining method, and brookite/g-C3N4/BiOBr ternary composites were prepared by loading BiOBr on the surface of brookite/g-C3N4. XRD and XPS analysis of the composites confirmed the formation of brookite TiO2/g-C3N4/BiOBr. SEM and TEM results confirmed the as-prepared composites were nanosized. The optimum loading amount of BiOBr was 30%. The photocatalytic results showed that the brookite/g-C3N4/30%BiOBr composites degraded rhodamine B completely under visible light irradiation. The degradation ratio of brookite/g-C3N4/30%BiOBr toward rhodamine B was nearly 100% for 2[Formula: see text]h, which was much higher than that of brookite TiO2 and brookite/g-C3N4 catalysts. The reason for the improvement of photocatalytic activity might be because the composites promoted the formation of superoxide radicals and the separation efficiency of photogenerated electron-hole pairs. The photocurrent density of the brookite/g-C3N4/30%BiOBr was about 10 times higher than that of pure brookite. In addition, the brookite/g-C3N4/BiOBr showed a good repeatablity of photocatalysis.

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The effect of iron doping on the photocatalytic activity of a Bi2WO6–BiVO4composite

RSC Advances ◽

10.1039/c6ra07811g ◽

2016 ◽

Vol 6 (59) ◽

pp. 54060-54068 ◽

Cited By ~ 11

Author(s):

Saranyoo Chaiwichian ◽

Khatcharin Wetchakun ◽

Sukon Phanichphant ◽

Wiyong Kangwansupamonkon ◽

Natda Wetchakun

Keyword(s):

Photocatalytic Activity ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Iron Doping ◽

Electron Hole

The formation of Fe-doped Bi2WO6–BiVO4composites could improve the separation efficiency of photogenerated electron–hole pairs, then increasing its photocatalytic activity.

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Enhancing the photocatalytic activity of ZnSn(OH)6 achieved by gradual sulfur doping tactics

Nanoscale ◽

10.1039/c9nr01103j ◽

2019 ◽

Vol 11 (19) ◽

pp. 9444-9456 ◽

Cited By ~ 3

Author(s):

Xinyi Lian ◽

Zhou Chen ◽

Xiang Yu ◽

Tingting Fan ◽

Yunyun Dong ◽

...

Keyword(s):

Photocatalytic Activity ◽

Optical Absorption ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Electron Hole ◽

Sulfur Doping

A gradual sulfur doping strategy was first proposed here to expand the optical absorption range, improve the separation efficiency of photogenerated electron–hole pairs, and finally enhance the photocatalytic activity.

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