Study on the Heterojunction Photocatalyst Nb2WO8/ZnO Prepared by Ball Milling Method

2011 ◽  
Vol 399-401 ◽  
pp. 1241-1245
Author(s):  
Jin Feng Zhang ◽  
Xiao Ling Yu ◽  
Wei Liu ◽  
Shi Fu Chen
Keyword(s):  
Photocatalytic Activity ◽  
Ball Milling ◽  
Photocatalytic Oxidation ◽  
Diffuse Reflectance Spectroscopy ◽  
Fluorescence Emission ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Activity Effect ◽  
Transmission Electron ◽  
Milling Method

Orthorhombic Nb2WO8 was synthesized by solid state reaction in Nb2O5-WO3 system. Heterojunction photocatalyst Nb2WO8/ZnO was prepared by ball milling. The structural and optical properties of the photocatalyst were characterized by X-ray powder diffraction, transmission electron microscopy, UV–vis diffuse reflectance spectroscopy, and fluorescence emission spectroscopy.The photocatalytic activity was evaluated by photocatalytic oxidation of rhodamine B and reduction of Cr6+. The results showed that the photocatalytic activity of the Nb2WO8/ZnO was higher than that of ZnO. When the amount of doped Nb2WO8 was 10 wt.% and the sample was ball milled for 9 h, the Nb2WO8/ZnO showed the optimal photocatalytic activity. Effect of ball milling time on the photocatalytic activity was also investigated. The mechanisms of the increase in the photocatalytic activity were discussed by the valence band principle.

scholarly journals Preparation, Characterization, and Activity Evaluation of CuO/F-TiO2Photocatalyst

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Zhang Jinfeng ◽  
Yang Yunguang ◽  
Liu Wei
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Ball Milling ◽  
Photocatalytic Oxidation ◽  
Diffuse Reflectance ◽  
Milling Time ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray ◽  
Transmission Electron ◽  
Ball Milling Time

CuO/F-TiO2nanoparticle photocatalyst was prepared by ball milling. The photocatalyst was characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy, and photoluminescence emission spectroscopy. The photocatalytic activity was evaluated by photocatalytic oxidation of rhodamine B and reduction of Cr2O7 2−. The results showed that, for F-TiO2photocatalyst, the photooxidation activity increases remarkably with the increasing amount of NH4F up to 1.0 g, and the photoreduction activity decreases gradually with the increase in the amounts of NH4F. For the CuO/F-TiO2photocatalyst, the photoreduction activity increases greatly with the increase in the amount of doped p-CuO up to 1.0 wt.%, and the photooxidation activity decreases rapidly with the increase in the amounts of doped p-CuO. Compared with pure TiO2, the photoabsorption wavelength range of the CuO/F-TiO2and F-TiO2photocatalysts red shifts and improves the utilization of the total spectrum. The effect of ball milling time on the photocatalytic activity of the photocatalysts was also investigated. The mechanisms of influence on the photocatalytic activity of the photocatalysts were also discussed.

scholarly journals Hydrothermal Synthesis of Iodine-Doped Nanoplates with Enhanced Visible and Ultraviolet-Induced Photocatalytic Activities

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Jiang Zhang ◽  
Zheng-Hong Huang ◽  
Yong Xu ◽  
Feiyu Kang
Keyword(s):  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Oxygen Vacancies ◽  
Diffuse Reflectance Spectroscopy ◽  
Synergetic Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Photocatalytic Activities

The iodine-doped Bi2WO6(I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (<400 nm) irradiation. The results of DRS analysis showed that the I-BWO and I2-BWO catalysts had narrower band gaps. XPS analysis proved that the multivalent iodine species including I0and were coadsorbed on the defect surface of Bi2WO6in I-BWO. The enhanced PL intensity revealed that a large number of defects of oxygen vacancies were formed by the doping of iodine. The enhanced photocatalytic activity of I-BWO for degradation of RhB was caused by the synergetic effect of a small crystalline size, a narrow band gap, and plenty of oxygen vacancies.

scholarly journals Photocatalytic Degradation of Estriol Using Iron-Doped TiO2 under High and Low UV-Irradiation

2018 ◽  
Author(s):  
Irwing M. Ramírez-Sánchez ◽  
Erick R. Bandala
Keyword(s):  
Photocatalytic Activity ◽  
Electron Microscope ◽  
Uv Irradiation ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Bet Surface Area ◽  
Doped Tio2 ◽  
X Ray ◽  
Transmission Electron ◽  
Iron Doped

Iron Doped TiO2 nanoparticles (Fe-TiO2) were synthesized and photocatalitically investigated under high and low fluence values of UV-radiation. The Fe-TiO2 physical characterization was performed using X-ray Powder Diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Diffuse Reflectance Spectroscopy (DRS), and X-Ray Photoelectron Spectroscopy (XPS) technique. The XPS evidenced that ferric ion (Fe3+) was in the lattice of TiO2 and co-dopants no intentionally added were also present due to the precursors of the synthetic method. The Fe3+ concentration played a key role in the photocatalytic generation of hydroxyl radical (&bull;OH) and estriol (E3) degradation. Fe-TiO2 materials accomplished E3 degradation, and it was found that the catalyst with 0.3 at. % content of Fe (0.3 Fe-TiO2) enhanced the photocatalytic activity under low UV-irradiation compared with no intentionally Fe-added TiO2 (zero-iron TiO2) and Aeroxide&reg; TiO2 P25. Furthermore, the enhanced photocatalytic activity of 0.3 Fe-TiO2 under low UV-irradiation may have applications when radiation intensity must be controlled, as in medical applications, or when strong UV absorbing species are present in water.

scholarly journals Defective TiO2 Core-Shell Magnetic Photocatalyst Modified with Plasmonic Nanoparticles for Visible Light-Induced Photocatalytic Activity

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 672 ◽  
Author(s):  
Zuzanna Bielan ◽  
Agnieszka Sulowska ◽  
Szymon Dudziak ◽  
Katarzyna Siuzdak ◽  
Jacek Ryl ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Phenol Degradation ◽  
Magnetic Core ◽  
Magnetic Photocatalyst ◽  
X Ray ◽  
Transmission Electron ◽  
First Time

In the presented work, for the first time, the metal-modified defective titanium(IV) oxide nanoparticles with well-defined titanium vacancies, was successfully obtained. Introducing platinum and copper nanoparticles (NPs) as surface modifiers of defective d-TiO2 significantly increased the photocatalytic activity in both UV-Vis and Vis light ranges. Moreover, metal NPs deposition on the magnetic core allowed for the effective separation and reuse of the nanometer-sized photocatalyst from the suspension after the treatment process. The obtained Fe3O4@SiO2/d-TiO2-Pt/Cu photocatalysts were characterized by X-ray diffractometry (XRD) and specific surface area (BET) measurements, UV-Vis diffuse reflectance spectroscopy (DR-UV/Vis), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Further, the mechanism of phenol degradation and the role of four oxidative species (h+, e−, •OH, and •O2−) in the studied photocatalytic process were investigated.

Synthesis of CeO2/e-HTiNbO5 Nanocomposite and Its Application for Photocatalytic Oxidation Desulfurization

NANO ◽  
2016 ◽  
Vol 11 (02) ◽  
pp. 1650018 ◽  
Author(s):  
Yuanjiao Zhang ◽  
Ningning Wang ◽  
Jie He ◽  
Liangguo Da ◽  
Zhong Li
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Oxidation ◽  
Diffuse Reflectance Spectroscopy ◽  
Proton Exchange ◽  
Light Irradiation ◽  
Laser Raman Spectroscopy ◽  
Natural Light ◽  
X Ray Diffraction ◽  
Laser Raman ◽  
Transmission Electron

Nanoscaled CeO2/e-HTiNbO5 composite was assembled by a facile process using colloidal TiNbO[Formula: see text] (e-HTiNbO5) nanosheet and CeO2 colloid as precursors at room temperature. The nanosheet e-HTiNbO5 was obtained through proton-exchange and exfoliation process from its parent KTiNbO5. The microstructures and properties of the as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Laser Raman spectroscopy (LRS), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS), etc. The photocatalytic activity of the obtained nanocomposite is evaluated by the adsorption and photocatalytic oxidation of ethyl mercaptan (EM) under natural light irradiation. The results show that CeO2 nanoparticles are dispersed uniformly on the surface of e-HTiNbO5 and the layered structure of e-HTiNbO5 nanosheet maintains integrity. The interaction between dispersed CeO2 particles and e-HTiNbO5 results in lower bandgap compared to its precursors, and the photocatalytic activity of CeO2/e-HTiNbO5 are enhanced under natural light irradiation.

scholarly journals Improved Visible Light Photocatalytic Activity for TiO2Nanomaterials by Codoping with Zinc and Sulfur

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Qianzhi Xu ◽  
Xiuying Wang ◽  
Xiaoli Dong ◽  
Chun Ma ◽  
Xiufang Zhang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Sunlight Irradiation ◽  
X Ray ◽  
Transmission Electron ◽  
Photoinduced Charge

S/Zn codoped TiO2nanomaterials were synthesized by a sol-gel method. X-ray diffraction, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy, photoluminescence spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the morphology, structure, and optical properties of the prepared samples. The introduction of Zn and S resulted in significant red shift of absorption edge for TiO2-based nanomaterials. The photocatalytic activity was evaluated by degrading reactive brilliant red X-3B solution under simulated sunlight irradiation. The results showed S/Zn codoped TiO2exhibited higher photocatalytic activity than pure TiO2and commercial P25, due to the photosynergistic effect of obvious visible light absorption, efficient separation of photoinduced charge carriers, and large surface area. Moreover, the content of Zn and S in the composites played important roles in photocatalytic activity of TiO2-based nanomaterials.

Photocatalytic Performance of BiOCl Nanosheets Composite with Graphene

2014 ◽  
Vol 496-500 ◽  
pp. 297-300 ◽  
Author(s):  
Bi Tao Liu ◽  
Liang Liang Tian ◽  
Ling Ling Peng
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Photocatalytic Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
Hydrothermal Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
One Step ◽  
High Migration

A series of composites of the high photoactivity of {001} facets exposed BiOCl and grapheme sheets (GS) were synthesized via a one-step hydrothermal reaction. The obtained BiOCl/GS photocatalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy, transmission electron microscopy (TEM), Ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy. The as-prepared BiOCl/GS photocatalyst showed enhanced photocatalytic activity for the degradation of methyl orange (MO) under UV and visible light (λ > 400 nm). The enhanced photocatalytic activity could be attributed to oxygen vacancies of the {001} facets of BiOCl/GS and the high migration efficiency of photo-induced electrons, which could suppress the charge recombination effectively.

scholarly journals Enhancement of Photocatalytic Activity of ZnO/SiO2by Nanosized Pt for Photocatalytic Degradation of Phenol in Wastewater

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
R. M. Mohamed ◽  
M. A. Barakat
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Surface Area ◽  
Diffuse Reflectance Spectroscopy ◽  
Sol Gel ◽  
Phenol Degradation ◽  
Synthetic Wastewater ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

ZnO- nanoparticles were synthesized by a sol-gel technique from and tetraethyl orthosilicate (TEOS). The synthesized samples were further modified by nanosized Pt from H2PtCl6solution through photoassisted deposition (PAD) and impregnation (Img) routes. The obtained samples were characterized by a series of techniques including X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy, N2adsorption, extended X-ray absorption fine structure (EXAFS), and transmission electron microscopy (TEM). The photocatalytic activity of the Pt-ZnO/ was evaluated by photocatalytic degradation of phenol in synthetic wastewater under UV-irradiation. Results obtained revealed that the surface area and the photocatalytic activity of the prepared samples were increased in the order ZnO/ < PAD: Pt-ZnO/ < img: Pt-ZnO/. The surface area decreased from 480 to 460 and 450 m2/g, while the efficiency of the phenol degradation increased from 80 to 85 and 100%, with the ZnO/, Img: Pt-ZnO-, and PAD: Pt-ZnO- samples, respectively.

scholarly journals AgBr/(Sr0.6Bi0.305)2Bi2O7 Heterostructured Composites: Fabrication, Characterization, and Significantly Enhanced Photocatalytic Activity

Catalysts ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 394 ◽  
Author(s):  
Xinling Wang ◽  
Di Zhu ◽  
Yan Zhong ◽  
Dianhui Wang ◽  
Chaohao Hu
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Photocatalytic Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
Precipitation Method ◽  
Light Illumination ◽  
X Ray ◽  
Transmission Electron ◽  
Pyrochlore Type

The pyrochlore-type (Sr0.6Bi0.305)2Bi2O7 (SBO) containing Bi3+ and Bi5+ mixed valent states was first investigated as a photocatalyst in our very recent work. To further improve the photocatalytic performance, AgBr/SBO heterostructured composites were synthesized by using a deposition-precipitation method. The characterization of phase structure, morphology, microstructure, elemental composition, and optical properties of the obtained products were performed using X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)TEM, X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectroscopy (UV-vis DRS). The photocatalytic activity of samples was evaluated by degrading methylene blue under visible light illumination. AgBr/SBO composites possess high stability and significantly enhanced photocatalytic performance. The improvement of photocatalytic activity is due to the enhanced light absorption and the separation of photoinduced electrons and holes on the interface of AgBr/SBO heterostructured composites.

Synthesis and Characterization of Titanium Dioxide Nanotubes for Photocatalytic Degradation of Aqueous Nitrobenzene in the Presence of Sunlight

2010 ◽  
Vol 657 ◽  
pp. 62-74 ◽  
Author(s):  
Rajesh J. Tayade ◽  
D.L. Key
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Tio2 Nanotubes ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Titanium Dioxide Nanotubes ◽  
X Ray ◽  
Tio2 Anatase ◽  
Transmission Electron

TiO2 derived nanotubes were prepared by hydrothermal treatment of TiO2 (anatase) powder in 10 M NaOH aqueous solution. The crystalline structure, band gap, and morphology of the TiO2 nanotubes were determined by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), Transmission Electron microscopy (TEM) and N2 adsorption (BET) at 77 K, respectively. It was observed that the surface area of the nanotubes was increased twelve times compared with TiO2 (anatase) powder. The results demonstrated that the photocatalytic activity of TiO2 nanotubes was higher than that of TiO2 (anatase) powder. The photocatalytic activity of the nanotubes was evaluated in presence of sunlight by degradation of aqueous nitrobenzene. Complete degradation of nitrobenzene was obtained in 4 hours using TiO2 nanotubes whereas 85% degradation was observed in case of TiO2 (anatase).

Sign in / Sign up

Export Citation Format

Share Document