Preparation and Photocatalytic Property of WO3-TiO2 /Ti Ceramic Film via Anodic Oxidation Treatment

2008 ◽  
Vol 368-372 ◽  
pp. 1500-1502 ◽  
Author(s):  
Yan Li Jiang ◽  
Hui Ling Liu ◽  
Zhao Hua Jiang ◽  
Zhong Ping Yao
Keyword(s):  
Visible Light ◽  
Anodic Oxidation ◽  
Rhodamine B ◽  
Recombination Rate ◽  
Visible Region ◽  
Photocatalytic Property ◽  
Electron Hole ◽  
Ceramic Film ◽  
High Efficient ◽  
Anodic Oxidation Treatment

The high efficient WO3-TiO2/Ti ceramic film was prepared on the surface of titanium by the approach of anodic oxidation in order to make the absorbable spectrum of catalyst spread to the visible region and restrain the high recombination rate of electron-hole pairs during photoreaction. The surface morphology and the distribution of elements were studied with scanning electron microscopy and energy dispersive spectroscopy. The phase composition of the films was investigated with XRD. The results showed that the main components in the coating were WO3, rutile TiO2 and anatase TiO2. The compound WO3-TiO2/Ti ceramic film enlarged the range of the reacting visible light and increased the absorbing intensity. The rhodamine B was successfully photodegraded under visible light irradiation by WO3-TiO2/Ti catalyst films. It was found that the highest degradation rate of rhodamine B was achieved through an optimal W dosage of 4.2 %(wt %) in WO3-TiO2/Ti ceramic film. It was also confirmed that the recombination rate of electron-hole pairs in WO3-TiO2/Ti ceramic film declined due to the existence of WO3 in TiO2/Ti ceramic film.

scholarly journals Preparation and Photocatalytic Performance for Degradation of Rhodamine B of AgPt/Bi4Ti3O12 Composites

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2206
Author(s):  
Gaoqian Yuan ◽  
Gen Zhang ◽  
Kezhuo Li ◽  
Faliang Li ◽  
Yunbo Cao ◽  
...  
Keyword(s):  
Visible Light ◽  
Noble Metal ◽  
Rhodamine B ◽  
Photocatalytic Performance ◽  
Bimetallic Nanoparticles ◽  
Resonance Effect ◽  
Visible Region ◽  
Photogenerated Electron ◽  
Pt Nanoparticles ◽  
Electron Hole

Loading a noble metal on Bi4Ti3O12 could enable the formation of the Schottky barrier at the interface between the former and the latter, which causes electrons to be trapped and inhibits the recombination of photoelectrons and photoholes. In this paper, AgPt/Bi4Ti3O12 composite photocatalysts were prepared using the photoreduction method, and the effects of the type and content of noble metal on the photocatalytic performance of the catalysts were investigated. The photocatalytic degradation of rhodamine B (RhB) showed that the loading of AgPt bimetallic nanoparticles significantly improved the catalytic performance of Bi4Ti3O12. When 0.10 wt% noble metal was loaded, the degradation rate for RhB of Ag0.7Pt0.3/Bi4Ti3O12 was 0.027 min−1, which was respectively about 2, 1.7 and 3.7 times as that of Ag/Bi4Ti3O12, Pt/Bi3Ti4O12 and Bi4Ti3O12. The reasons may be attributed as follows: (i) the utilization of visible light was enhanced due to the surface plasmon resonance effect of Ag and Pt in the visible region; (ii) Ag nanoparticles mainly acted as electron acceptors to restrain the recombination of photogenerated electron-hole pairs under visible light irradiation; and (iii) Pt nanoparticles acted as electron cocatalysts to further suppress the recombination of photogenerated electron-hole pairs. The photocatalytic performance of Ag0.7Pt0.3/Bi4Ti3O12 was superior to that of Ag/Bi4Ti3O12 and Pt/Bi3Ti4O12 owing to the synergistic effect between Ag and Pt nanoparticles.

FABRICATION OF BIPHASE BiVO4 PARTICLES WITH ENHANCED PHOTOCATALYTIC PERFORMANCE VIA A SURFACTANT-FREE HYDROTHERMAL ROUTE

2016 ◽  
Vol 23 (05) ◽  
pp. 1650032 ◽  
Author(s):  
HONGZHI QIAN ◽  
MIN LAI ◽  
XIAOGU HUANG ◽  
WEI WANG ◽  
CHAOQI XU ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Rhodamine B ◽  
Recombination Rate ◽  
Photocatalytic Performance ◽  
Bismuth Vanadate ◽  
Light Irradiation ◽  
Hydrothermal Route ◽  
Electron Hole

Biphase bismuth vanadate (BiVO4) particles have been synthesized using a surfactant-free hydrothermal strategy. Biphase BiVO4 were formed at [Formula: see text], 5 and 7 with a bandgap between 2.28[Formula: see text]eV and 2.86[Formula: see text]eV, which are those of monoclinic and tetragonal phases, respectively. Photocatalytic tests on the degradation of rhodamine B (RhB) under visible-light irradiation showed that biphase BiVO4 with both monoclinic and tetragonal structures synthesized at [Formula: see text] achieved enhanced photocatalytic performance in comparison with pure monoclinic and tetragonal phases, which was attributed to the heterostructures leading to low recombination rate of electron–hole pairs.

scholarly journals Synthesis and characterization of Z-scheme heterostructure CoWO4/g-C3N4 as a visible-light photocatalyst for removal of organic pollutant

2021 ◽  
Vol 10 (2) ◽  
pp. 59-63
Author(s):  
Hai Pham Viet ◽  
Anh Dao Thi Ngoc ◽  
Viet Nguyen Minh ◽  
Ha Tran Thi Viet ◽  
Dang Do Van ◽  
...  
Keyword(s):  
Visible Light ◽  
Rhodamine B ◽  
High Performance ◽  
Organic Pollutant ◽  
Photogenerated Electron ◽  
Morphological Properties ◽  
Electron Hole ◽  
Visible Light Photocatalyst ◽  
Photocatalytic Activities

In this study, direct Z–scheme heterostructure CoWO4/g-C3N4 was synthesized by a facile hydrothermal method. The structural, morphological properties of the prepared samples were characterised by XRD, SEM, UV–Vis and PL measurements. The as-obtained heterostructure CoWO4/g-C3N4 exhibited enhanced photocatalytic activities toward the degradation of Rhodamine B under visible light irradiation with 92% Rhodamine B removal after 80 minutes irritation, which exceeded pristine g-C3N4 and CoWO4. The enhanced photocatalytic performance ascribed to interfacial contact between g-C3N4 and CoWO4, thus further inhibiting the recombination of photogenerated electron/hole pairs. It is anticipated that the construction of Z–scheme heterostructure CoWO4/g-C3N4 is an effective strategy to develop high-performance photocatalysts for the degradation of organic pollutants in water.

scholarly journals Enhanced Transformation of Atrazine by High Efficient Visible Light-Driven N, S-Codoped TiO2Nanowires Photocatalysts

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yanlin Zhang ◽  
Honghai Wu ◽  
Peihong Liu
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Advanced Oxidation Process ◽  
Light Irradiation ◽  
Solar Irradiation ◽  
Electron Hole ◽  
Toc Removal ◽  
High Efficient ◽  
Endocrine Disrupting ◽  
Visible Light Driven

Advanced oxidation process using titanium dioxide as a photocatalyst under solar irradiation is one of the most attractive technologies to eliminate atrazine, an endocrine disrupting and carcinogen contaminant. The N, S-codoped TiO2nanowires at the calcination of 600°C obtained by a facile hydrothermal method revealed the best photocatalytic performance for the degradation of atrazine under visible light irradiation compared to N, S-codoped TiO2nanoparticles and S-doped TiO2nanowires. TOC removal experiment also exhibited the similar result and achieved 63% of atrazine mineralization within 6 h. The degradation of atrazine was driven mainly by•OH and holes during the photocatalytic process. Reactive species quantities such•OH andO2•-generated by N, S-codoped TiO2nanowires under visible light irradiation were much more than those of S-doped TiO2nanowires and N, S-codoped TiO2nanoparticles. These results were mainly attributed to the synergistic effect of N and S doping in narrowing the band gap, remarkable increase in electron-hole separation, extending the anatase-to-rutile transformation temperature above 600°C, and preferentially exposing high reactive{001}crystal facets of anatase.

scholarly journals Hydrothermal Preparation of Visible-Light-Driven N-Br-CodopedTiO2Photocatalysts

2008 ◽  
Vol 2008 ◽  
pp. 1-7 ◽  
Author(s):  
Yonggang Sheng ◽  
Yao Xu ◽  
Dong Jiang ◽  
Liping Liang ◽  
Dong Wu ◽  
...  
Keyword(s):  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Synergetic Effect ◽  
Visible Region ◽  
Charge Compensation ◽  
Direct Reaction ◽  
Hydrothermal Preparation ◽  
Electron Hole ◽  
Visible Light Driven ◽  
Hole Recombination

Using a facile hydrothermal method, N-Br-codopedTiO2photocatalyst that had intense absorption in visible region was prepared at low temperature (100°C), through a direct reaction between nanocrystalline anataseTiO2solution and cetyltrimethylammonium bromide (CTAB). The results of X-ray photoelectron spectroscopy (XPS) showed the existence of N-Ti-N, O-Ti-N-R,Ti3+(attribute to the doped Br atoms by charge compensation), andTiOxNyspecies, indicating the successful codoping of N and Br atoms, which were substituted for lattice oxygen without any influence on the crystalline phase ofTiO2. In contrast to the N-doped sample, the N-Br-codopedTiO2photocatalyst could more readily photodegrade methylene blue (MB) under visible-light irradiation. The visible-light catalytic activity of thus-prepared photocatalyst resulted from the synergetic effect of the doped nitrogen and bromine, which not only gave high absorbance in the visible-light range, but also reduced electron-hole recombination rate.

scholarly journals GQD/Bi2O3 Composite for high-efficient photocatalysts

2020 ◽  
Vol 213 ◽  
pp. 02037
Author(s):  
Chengli Tang ◽  
Limei Zhang
Keyword(s):  
Visible Light ◽  
Active Sites ◽  
Minority Carrier ◽  
Diffusion Length ◽  
Graphene Quantum Dots ◽  
Photocatalytic Efficiency ◽  
Electron Hole ◽  
Minority Carrier Diffusion Length ◽  
High Efficient ◽  
Visible Light Photocatalytic

Bismuth oxide (Bi2O3) is one of the potential visible-light photocatalytic materials, however, due to low electron mobility and short minority carrier diffusion length, the photocatalytic activity of Bi2O3 is restricted. The GQD/Bi2O3 composites were synthesized stably depositing single-crystalline graphene quantum dots (GQDs) with absorption edge at ~10nm, prepared by using a top-down method. The GQDBi2O3 heterojunctions were successfully established, the photo-generated electrons transfer from the Bi2O3 to the GQDs at the interface of the GQD-Bi2O3 heterojunctions, result in efficient electron-hole pairs separation and higher photocatalytic efficiency. The optimum visible performance is achieved at GQD content of 1.0 wt %, the RhB dye was nearly completely decoloured after 90 min of visible-light irradiation, and then decrease at higher doping levels due to the thicker GQD layer will cover the active sites of Bi2O3, thus leading to the greatly reduced catalytic activity.

Nitrogen-Doped Nano-TiO2 Ceramic Film: Fabrication and Application to Photocatalysis

2010 ◽  
Vol 105-106 ◽  
pp. 746-749
Author(s):  
Yan Li Jiang ◽  
Zhong Ping Yao ◽  
Li Juan Yang ◽  
Yan Liu ◽  
Zhao Hua Jiang ◽  
...  
Keyword(s):  
Visible Region ◽  
Reduction Rate ◽  
Electron Hole ◽  
Surface Appearance ◽  
Tio2 Photocatalysts ◽  
Nitrogen Doped ◽  
Ceramic Film ◽  
Distribution Of Elements ◽  
Film Fabrication ◽  
Main Components

Owing to the defects of the fixed TiO2 photocatalysts, the research employed the approach of anodic oxidation to produce high efficiend N-TiO2/Ti ceramic film oxidized on the surface of titanium, in order to make the absorbable spectrum of light catalyst spread to the visible region and constrain the high recombination rate of electron-hole pairs during photoreaction. The surface appearance and the distribution of elements have been checked with scanning electron microscopy and EPMA. The microcrystal structure of the films has been checked with XRD. The results showed that the main components of nitrogen-doped catalyzer were rutile and anatase, meanwhile, the nitrogen element distributing on the film was fairly uniform. Films of N-TiO2 photocatalysis reduction K2CrO4 revealed that with the amount of N-contained increased, the rate of reduction K2CrO4 decreased under ultraviolet light while that increased under visible light. It was found that the highest reduction rate of K2CrO4 was achieved through an optimal (NH4)2S2O8 dosage of 0.4g/L in ceramic film prepared processes.

In situ bubble template promoted facile preparation of porous g-C3N4 with excellent visible-light photocatalytic performance

RSC Advances ◽  
2015 ◽  
Vol 5 (78) ◽  
pp. 63264-63270 ◽  
Author(s):  
Lei Shi ◽  
Lin Liang ◽  
Fangxiao Wang ◽  
Mengshuai Liu ◽  
Tao Liang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Recombination Rate ◽  
Photocatalytic Performance ◽  
Electron Hole ◽  
Facile Preparation ◽  
Bubble Template ◽  
Splitting Water ◽  
Visible Light Photocatalytic

pg-C3N4 prepared through in situ bubble template showed large surface area and low recombination rate of photoinduced electron–hole pairs, leading to enhanced visible-light photocatalytic activity for degrading pollutants and splitting water to H2.

scholarly journals A Facile Synthesis of Visible-Light Driven Rod-on-Rod like α-FeOOH/α-AgVO3 Nanocomposite as Greatly Enhanced Photocatalyst for Degradation of Rhodamine B

Catalysts ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 392 ◽  
Author(s):  
Meng Sun ◽  
Raja Senthil ◽  
Junqing Pan ◽  
Sedahmed Osman ◽  
Abrar Khan
Keyword(s):  
Electron Microscopy ◽  
Visible Light ◽  
Rhodamine B ◽  
Diffuse Reflectance Spectroscopy ◽  
Hole Pair ◽  
Precipitation Method ◽  
Aqueous Environment ◽  
Electron Hole ◽  
X Ray ◽  
Electron Hole Pair

In this work, we have synthesized the rod-on-rod–like α-FeOOH/α-AgVO3 nanocomposite photocatalysts with the different amounts of solvothermally synthesized α-FeOOH nanorods via a simple co-precipitation method. The as-synthesized photocatalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, UV−Visible diffuse reflectance spectroscopy, scanning electron microscopy (SEM), element mapping, high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS) analysis. The observed SEM images show that both α-AgVO3 and α-FeOOH exhibits the rod-shaped morphology with nano size. Furthermore, the photocatalytic activities of the obtained photocatalysts were evaluated towards the degradation of Rhodamine B (RhB) under visible-light irradiation. It is demonstrated that the 3 mg α-FeOOH added to the α-FeOOH/α-AgVO3 nanocomposite exhibited an enhanced photocatalytic performance as compared with the pure α-AgVO3 and α-FeOOH. This significant improvement can be attributed to the increased photo-excited electron-hole pair separation efficiency, large portion of visible-light absorption ability and the reduced recombination of the electron-hole pair. The recycling test revealed that the optimized nanocomposite exhibited good photostability and reusability properties. In addition, the believable photodegradation mechanism of RhB using α-FeOOH/α-AgVO3 nanocomposite is proposed. Hence, the developed α-FeOOH/α-AgVO3 nanocomposite is a promising material for the degradation of organic pollutants in an aqueous environment.

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