scholarly journals Enhancing Photocatalytic Performance through Tuning the Interfacial Process between -Assembled and Pt-Loaded Microspheres

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Jun Zhang ◽  
Liping Li ◽  
Guangshe Li
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Performance ◽  
Lattice Structure ◽  
Pt Nanoparticles ◽  
Photogenerated Electrons ◽  
Excellent Photocatalytic Activity ◽  
Ultraviolet Light Irradiation ◽  
Systematic Sample ◽  
Utility Rate ◽  
High Dielectric

This work reports on a simple two-step approach to rutile TiO2-assembled microspheres loaded by Pt with an aim to tune semiconductor-metal interfacial processes for enhancing the photocatalytic performance. Systematic sample characterizations and structural analysis indicate that Pt loading did not produce any significant influences on the lattice structure of TiO2-assembled microspheres. Instead, upon Pt loading, Schottky barrier was formed in the interfaces between microspheres and Pt nanoparticles, which inhabited efficiently the recombination of photo-generated electron-hole pairs essential for the photocatalytic activities. In addition, TiO2microspheres also showed a capacity of electrons storage and releasing as represented by a high dielectric constant, which increased the utility rate of photogenerated electrons. All these structural advantages contribute to the excellent photocatalytic activity under ultraviolet light irradiation. The interfacial process between microspheres and Pt nanoparticles was further tuned through adjusting the loading Pt content of metal Pt. As a consequence, the best photocatalytic activity on TiO2was obtained at 0.85 wt% Pt loading, above or below which photocatalytic activity was apparently decreased.

A novel cobalt ion implanted pyridylporphyrin/graphene oxide assembly for enhanced photocatalytic hydrogen production

2018 ◽  
Vol 22 (09n10) ◽  
pp. 877-885 ◽  
Author(s):  
Qiang Luo ◽  
Kun Zhu ◽  
Shi-Zhao Kang ◽  
Lixia Qin ◽  
Sheng Han ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Photocatalytic Activity ◽  
Graphene Oxide ◽  
Hydrogen Production ◽  
Hydrogen Evolution ◽  
Electrostatic Interaction ◽  
Strong Interaction ◽  
Photocatalytic Performance ◽  
Coordination Interaction ◽  
Photogenerated Electrons

By facilely pre-implanting Co[Formula: see text] ions in the graphene oxide, a novel 5,15-diphenyl-10,20-di(4-pyridyl)porphyrin pillared graphene oxide was fabricated by means of electrostatic interaction and coordination interaction. It was shown that the morphology and the structure of graphene oxide and pyridylporphyrin nanocomposite were modified by introducing Co[Formula: see text] ions on the interface between graphene oxide and pyridylporphyrin. Furthermore, it was found that the photocatalytic hydrogen evolution activity over the Co[Formula: see text] ions implanted in the graphene oxide and pyridylporphyrin nanocomposite was evidently higher than in the graphene oxide and pyridylporphyrin nanocomposite without Co[Formula: see text]. This confirmed that strong interaction and efficient electron transfer between pyridylporphyrin and graphene oxide are the important reasons for the enhanced photocatalytic activity for hydrogen evolution. Subsequently, this technique will be a simple and efficient approach to optimize the transfer pathway of photogenerated electrons and to improve photocatalytic performance by implanting metal ions in the interface of nanocomposites.

TiO2 composite films on different substrates with enhanced visible light photocatalytic performance

2020 ◽  
Vol 13 (07) ◽  
pp. 2051037
Author(s):  
Ke Han ◽  
Guobao Li ◽  
Fang Li ◽  
Mingming Yao
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Photocatalytic Performance ◽  
Sol Gel ◽  
Composite Films ◽  
Methyl Green ◽  
Photogenerated Electrons

For the sake of improving the photocatalytic performance of TiO2, we prepared the B/Ag/Fe tridoped TiO2 films on common glass and stone substrates by the sol–gel method. In this work, the optical absorption, recombination of photogenerated electrons (e−) and holes (h[Formula: see text]), crystal types, thermal stability, composition, specific surface area and photocatalytic activity of the modified TiO2 films were investigated. The results indicated that B/Ag/Fe tridoping not only enhanced the absorption of visible light by TiO2, but inhibited the recombination of electron–hole (e−/h[Formula: see text]) pairs. The tridoping also promoted the formation of anatase and prevented the transformation of anatase to rutile at high temperature. The composite TiO2 has a large specific surface area, about three times that of pure TiO2. The photocatalytic activity of the TiO2 films were evaluated by methyl green (MG) and formaldehyde degradation. In all samples, the B/Ag/Fe tridoped TiO2 film exhibited the highest degradation rate of MG under both ultraviolet and visible light irradiation. The improvement of photocatalytic performance of TiO2 films is due to the synergistic effect of the B/Ag/Fe tridoping, which enhances the absorption of visible light and prolongs the lifetime of e−/h[Formula: see text] pairs and facilitates transfer of interface charge.

Characterization and Photocatalytic Activity of Microspheres ZnO by Hydrothermal Method

2019 ◽  
Vol 814 ◽  
pp. 487-492
Author(s):  
Xi Hao Lin ◽  
Pei Song Tang ◽  
Bei Bei Wang ◽  
Hai Qiang Tang
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Hydrothermal Method ◽  
Diffuse Reflectance Spectroscopy ◽  
Raw Materials ◽  
Average Diameter ◽  
High Photocatalytic Activity ◽  
X Ray Diffraction ◽  
Excellent Photocatalytic Activity ◽  
Ultraviolet Light Irradiation

Using zinc acetate, glycerol alcohol and sodium hydroxide as principal raw materials, the ZnO microspheres were prepared by hydrothermal method at 200°C. The samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and diffuse reflectance spectroscopy (DRS). Using methyl orange as the degradation object, the photocatalytic activities and recycling stability of ZnO were characterized. The results show that ZnO samples are spherical and the average diameter is approximately 3-4μm. Moreover, the bandgap width is 3.1eV. Under ultraviolet light irradiation, it is testified that ZnO shows a excellent photocatalytic activity for the degradation of methyl orange. From experience, we can draw a conclusion that the ZnO samples were in line with first-order kinetics, with an apparent rate constant of 0.016min-1. At the same time, ZnO showed excellent recycling performance. Although the samples have been recycled three times, it still maintained high photocatalytic activity.

Characteristic and photocatalytic performance of magnetic photocatalyst β-Bi2O3/MnxZn1−xFe2O4 synthesized by hydrothermal and calcination method

2021 ◽  
Author(s):  
Qiyuan Zhang ◽  
Yahan Yang ◽  
Yong Cheng ◽  
Longjun Xu ◽  
Chenglun Liu
Keyword(s):  
Magnetic Field ◽  
Photocatalytic Activity ◽  
Degradation Rate ◽  
Photocatalytic Performance ◽  
Photocatalytic Efficiency ◽  
Magnetic Photocatalyst ◽  
Magnetization Saturation ◽  
Excellent Photocatalytic Activity ◽  
Calcination Method ◽  
Optimum Sample

A magnetic photocatalyst [Formula: see text]-Bi2O3/Mn[Formula: see text]Zn[Formula: see text]Fe2O4 (Bi2O3/MZF) was fabricated by hydrothermal and calcination method, and characterized by XRD, FTIR, XPS and SEM, BET and VSM. The photocatalytic efficiency was measured by the degradation experiment of Rhodamine B (RhB). The degradation rate of the optimum sample Bi2O3/MZF (10 wt.%) could reach 96.8% after 3 h under visible light, and was improved significantly compared with pure [Formula: see text]-Bi2O3 due to the larger pore size (11.76 nm) and specific surface area (17.87 m2 ⋅ g[Formula: see text]. Meanwhile, the Bi2O3/MZF (10 wt.%) could be recovered under the external magnetic field due to its high magnetization saturation (9.22 emu ⋅ g[Formula: see text]. After reusing three times, the Bi2O3/MZF could still maintain the excellent photocatalytic activity and structural stability.

Fabrication of N-doped Reduced Graphene Oxide/Ag3PO4 Nanocomposite with Excellent Photocatalytic Activity for the Degradation of Organic Pollutants

NANO ◽  
2017 ◽  
Vol 12 (01) ◽  
pp. 1750013 ◽  
Author(s):  
Longhai Feng ◽  
Lirong Kong ◽  
Zhenyuan Ji ◽  
Yi Wang ◽  
Xiaoping Shen ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Photocatalytic Performance ◽  
Organic Pollutant ◽  
Charge Carriers ◽  
Simulated Solar Light ◽  
Solar Light Irradiation ◽  
Reduced Graphene ◽  
Excellent Photocatalytic Activity

An efficient N-doped reduced graphene oxide (N-RGO)/Ag3PO4 nanocomposite with enhanced photocatalytic activity has been prepared through a facile solution-based approach. Since N-RGO could offer more sites for the anchoring of Ag3PO4 nanoparticles, and effectively promote the charge carriers separation and transfer due to its high electrical conductivity, the photocatalytic activity of N-RGO/Ag3PO4 nanocomposite is much higher than bare Ag3PO4 and N-RGO in the degradation of phenol pollutant under simulated solar light irradiation. The mechanism for the photocatalytic process was also investigated. The excellent photocatalytic performance makes the N-RGO/Ag3PO4 nanocomposite a promising photocatalyst for organic pollutant treatment.

Heterostructured g-C3N4/Ag–TiO2 composites with efficient photocatalytic performance under visible-light irradiation

RSC Advances ◽  
2015 ◽  
Vol 5 (69) ◽  
pp. 56136-56144 ◽  
Author(s):  
Mengqiao Zang ◽  
Lei Shi ◽  
Lin Liang ◽  
Defeng Li ◽  
Jianmin Sun
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Photocatalytic Performance ◽  
Synergistic Effects ◽  
High Photocatalytic Activity ◽  
Light Irradiation ◽  
Enhanced Absorption ◽  
Efficient Separation ◽  
Photogenerated Electrons

The heterostructured g-C3N4/Ag–TiO2 composites exhibited high photocatalytic activity, which was attributed to the synergistic effects of the enhanced absorption of visible light and the efficient separation rates for photogenerated electrons-holes.

Tuning of the photocatalytic performance of g-C3N4 by polyoxometalates under visible light

2017 ◽  
Vol 46 (46) ◽  
pp. 16019-16024 ◽  
Author(s):  
Gang Yan ◽  
Xiaojia Feng ◽  
Liguang Xiao ◽  
Wenguang Xi ◽  
Huaqiao Tan ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Performance ◽  
Spatial Separation ◽  
High Photocatalytic Activity ◽  
Electron Traps ◽  
Photogenerated Electrons

Polyoxometalate/g-C3N4 composites were prepared with Keggin POMs and g-C3N4. POMs used as electron traps can efficiently promote the spatial separation of photogenerated electrons and holes of C3N4, which resulted in a high photocatalytic activity towards MO degradation.

Enhanced Photocatalytic Performance of Heterojunction BiOI/BiOIO3 Nanocomposites Under Simulated Solar Light

NANO ◽  
2017 ◽  
Vol 12 (03) ◽  
pp. 1750027 ◽  
Author(s):  
Yi Ling Qi ◽  
Xu Chun Song ◽  
Yi Fan Zheng
Keyword(s):  
Photocatalytic Activity ◽  
Electric Field ◽  
Visible Light ◽  
Rhodamine B ◽  
Room Temperature ◽  
Photocatalytic Performance ◽  
Deposition Method ◽  
Simulated Solar Light ◽  
Photogenerated Electrons ◽  
Light Absorber

Novel heterostructure BiOI/BiOIO3 nanocomposites were successfully prepared through a facile deposition method at room temperature. BiOIO3 is a noncentrosymmetric compound that has an internal self-built electric field. BiOI was applied as a visible light absorber to sensitize semiconductors owing to its smallest bandgap. The coupling between BiOIO3 and BiOI can combine their advantages and improve photocatalytic properties. Compared with the single BiOI and BiOIO3, the heterostructure BiOI/BiOIO3 nanocomposites displayed a significantly enhanced photocatalytic activity for the Rhodamine B (RhB) degradation. The enhanced photocatalytic performance is deduced closely related to the formation of BiOI/BiOIO3 heterojunction interface whose presence is regarded to be a favorable factor for the transfer and separation of the photogenerated electrons and holes.

scholarly journals Photocatalytic Reduction of CO2to Methane on Pt/TiO2Nanosheet Porous Film

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Li Qiu-ye ◽  
Zong Lan-lan ◽  
Li Chen ◽  
Cao Yu-hui ◽  
Wang Xiao-dong ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Separation Efficiency ◽  
Pt Nanoparticles ◽  
Porous Film ◽  
Bet Surface Area ◽  
X Ray Diffraction ◽  
Porous Films ◽  
Transmission Electron ◽  
Excellent Photocatalytic Activity ◽  
Average Size

Anatase TiO2nanosheet porous films were prepared by calcination of the orthorhombic titanic acid films at 400°C. They showed an excellent photocatalytic activity for CO2photoreduction to methane, which should be related to their special porous structure and large Brunauer-Emmett-Teller (BET) surface area. In order to further improve the photocatalytic activity, Pt nanoparticles were loaded uniformly with the average size of 3-4 nm on TiO2porous films by the photoreduction method. It was found that the loading of Pt expanded the light absorption ability of the porous film and improved the transformation efficiency of CO2to methane. The conversion yield of CO2to methane on Pt/TiO2film reached 20.51 ppm/h·cm2. The Pt/TiO2nanosheet porous film was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), and ultraviolet-visible light diffuse reflectance spectra (UV-vis DRS). Moreover, the transient photocurrent-time curves showed that the Pt/TiO2nanosheet porous film exhibited higher photocurrent, indicating that the higher separation efficiency of the photogenerated charge carriers was achieved.

scholarly journals Synergistic Effect of Ag and Cu Codoping on the Structural, Optical and Photocatalytic Performance of BiVO4

2021 ◽  
Author(s):  
Maheskumar Velusamy ◽  
Zhenyi Jiang ◽  
Yanming Lin ◽  
Vidhya Bhojan ◽  
Sasikumar S
Keyword(s):  
Photocatalytic Activity ◽  
Synergistic Effect ◽  
Photocatalytic Performance ◽  
Superoxide Radical ◽  
Life Time ◽  
Charge Carriers ◽  
Radical Species ◽  
Excellent Photocatalytic Activity ◽  
Superior Property ◽  
Co Doped

Abstract In this work, Ag or/and Cu doped BiVO 4 samples has been prepared successfully via hydrothermal and photoreduction method. Ag/Cu co-doped BiVO 4 exhibited high photocatalytic degradation efficiency in the degradation of methylene blue (MB) and displayed a significantly superior property compared to pure BiVO 4, as well as only Ag or Cu doped BiVO 4 upon exposure to visible light source. Interestingly, we found that enhanced photocatalytic activity of Ag/Cu co-doped BiVO 4 arises from the synergistic effect between the Ag and Cu co-doped BiVO 4 with smaller crystalline size, improved photocatalytic reaction sites, improved life-time and enhanced separation of photogenerated charge carriers which are confirmed using different characterization techniques. The degradation of MB was mainly indicated by superoxide radical species as confirmed by the trapping experiment. Based on the collective results obtained an excellent photocatalytic activity in Ag/Cu co-doped BiVO 4 has been confirmed.

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