scholarly journals A CeO2 Semiconductor as a Photocatalytic and Photoelectrocatalytic Material for the Remediation of Pollutants in Industrial Wastewater: A Review

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1435
Author(s):  
Elzbieta Kusmierek
Keyword(s):  
Photocatalytic Activity ◽  
Industrial Wastewater ◽  
Green Technology ◽  
Experimental Conditions ◽  
Oxide Semiconductors ◽  
Composite Photocatalyst ◽  
Conduction Bands ◽  
Photoelectrocatalytic Degradation ◽  
Valence Bands ◽  
Photocatalytic Reactions

The direct discharge of industrial wastewater into the environment results in serious contamination. Photocatalytic treatment with the application of sunlight and its enhancement by coupling with electrocatalytic degradation offers an inexpensive and green technology enabling the total removal of refractory pollutants such as surfactants, pharmaceuticals, pesticides, textile dyes, and heavy metals, from industrial wastewater. Among metal oxide—semiconductors, cerium dioxide (CeO2) is one of the photocatalysts most commonly applied in pollutant degradation. CeO2 exhibits promising photocatalytic activity. Nonetheless, the position of conduction bands (CB) and valence bands (VB) in CeO2 limits its application as an efficient photocatalyst utilizing solar energy. Its photocatalytic activity in wastewater treatment can be improved by various modification techniques, including changes in morphology, doping with metal cation dopants and non-metal dopants, coupling with other semiconductors, and combining it with carbon supporting materials. This paper presents a general overview of CeO2 application as a single or composite photocatalyst in the treatment of various pollutants. The photocatalytic characteristics of CeO2 and its composites are described. The main photocatalytic reactions with the participation of CeO2 under UV and VIS irradiation are presented. This review summarizes the existing knowledge, with a particular focus on the main experimental conditions employed in the photocatalytic and photoelectrocatalytic degradation of various pollutants with the application of CeO2 as a single and composite photocatalyst.

scholarly journals Copper oxide supported on graphene for phodegradation of rhodamine B

2015 ◽  
Vol 11 (4) ◽  
Author(s):  
Nurul Sahida Hassan ◽  
Nurul Jamilah Roslani ◽  
Aishah Abdul Jalil ◽  
Sugeng Triwahyono ◽  
Nur Fatien Salleh ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Copper Oxide ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Industrial Wastewater ◽  
Water Contamination ◽  
X Ray Diffraction ◽  
Composite Photocatalyst ◽  
X Ray ◽  
First Order

In recent years, dyes are one of the major sources of the water contamination that lead to environmental problems. For instance, Rhodamine B (RhB) which was extensively used as a colorant in textile industries is toxic and carcinogenic. Among many techniques, photocatalytic degradation become the promising one to remove those dyes from industrial wastewater. Recently, graphene has shown outstanding performance in this application due to its intrinsic electron delocalisation which promotes electron transport between composite photocatalyst and pollutant molecules. While, copper oxide (CuO) is well-known has a lower bandgap energies compared to other semiconductors. Therefore, in this study, copper oxide supported on graphene (CuO/G) was prepared and its photocatalytic activity was tested on degradation of RhB. The catalysts were characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) Spectroscopy. The results showed that the interaction between copper and graphene support could enhance the photocatalytic activity. The 5 wt% CuO/G was found to give the highest degradation (95%) of 10 mg L-1 of RhB solution at pH 7 using 1 g L-1 catalyst after 4 hours under visible light irradiation. The photodegradation followed the pseudo first-order Langmuir-Hinshelwood kinetic model. This study demonstrated that the CuO/G has a potential to be used in photocatalytic degradation of various organic pollutants.

scholarly journals Preparation of Multicycle GO/TiO2 Composite Photocatalyst and Study on Degradation of Methylene Blue Synthetic Wastewater

2019 ◽  
Vol 9 (16) ◽  
pp. 3282 ◽  
Author(s):  
Zhongtian Fu ◽  
Song Zhang ◽  
Zhongxue Fu
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Raw Materials ◽  
Anatase Phase ◽  
Pure Tio2 ◽  
Synthetic Wastewater ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Composite Photocatalyst ◽  
Initial Ph

A series of composite photocatalysts were prepared by using graphene oxide (GO) prepared by modified Hummers method and TiO2 hydrogel prepared by using butyl titanate as raw materials. The composite photocatalyst was characterized through scanning electron microscope（SEM）, x ray diffraction （XRD）, and Raman spectroscopy, and the degradation effect of pure TiO2 and composite photocatalyst on methylene blue (MB) dye wastewater under different experimental conditions was studied. The results showed that TiO2 in composite photocatalyst was mainly anatase phase and its photocatalytic activity was better than pure TiO2. When the addition of GO reached 15 wt%, the photocatalytic activity was the highest. When 200 mg composite photocatalyst was added to 200 mL synthetic wastewater with a concentration of 10 mg/L and an initial pH of about 8, the degradation rate could reach 95.8% after 2.5 h. It is presumed that the photogenerated charges of GO/TiO2 composite photocatalyst may directly destroy the luminescent groups in the MB molecule and thus decolorize the wastewater, and no other new luminescent groups are generated during the treatment.

Experimental Research of Visible Light-Induced Photocatalytic Oxidation Effects of SO2 by N-Doping Nano-TiO2

2012 ◽  
Vol 486 ◽  
pp. 12-17
Author(s):  
Shu Qin Wang ◽  
Yin Tao Wang ◽  
Yan Dong Liu
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Oxidation ◽  
Sol Gel ◽  
Particle Diameter ◽  
Experimental Conditions ◽  
N Doping ◽  
Photocatalytic Reactions ◽  
Oxidation Mechanisms ◽  
Lamp Illumination

N-doping nanoTiO2 was prepared by sol-gel method. The TEM,XRD,XPS,BET and UV techniques were used to characterize the crystalline structure.The photocatalytic oxidation effects of SO2 were studied with the fluorescence lamp illumination under the different conditions. The visible light-induced photocatalytic oxidation mechanisms of SO2 were discussed. The results showed that N-doping nanoTiO2 increase the visible-light responsive photocatalytic activity because of the increase of the surface area, O2 lacuna and small particle diameter. There are the optima of the dosage and amount of O2. The removal efficiency of SO2 was greater than 95% under the experimental conditions. The photocatalytic reactions of SO2 included two parts-adsorption and oxidation. The results provide some references for the SO2 control and further application of nanoTiO2.

scholarly journals Semiconductor Electrode Materials Applied in Photoelectrocatalytic Wastewater Treatment—an Overview

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 439 ◽  
Author(s):  
Elzbieta Kusmierek
Keyword(s):  
Industrial Wastewater ◽  
Electrode Materials ◽  
Raw Materials ◽  
Sewage Treatment ◽  
High Energy ◽  
Inorganic Pollutants ◽  
Experimental Conditions ◽  
Treatment Processes ◽  
Photoelectrocatalytic Degradation ◽  
High Energy Consumption

Industrial sources of environmental pollution generate huge amounts of industrial wastewater containing various recalcitrant organic and inorganic pollutants that are hazardous to the environment. On the other hand, industrial wastewater can be regarded as a prospective source of fresh water, energy, and valuable raw materials. Conventional sewage treatment systems are often not efficient enough for the complete degradation of pollutants and they are characterized by high energy consumption. Moreover, the chemical energy that is stored in the wastewater is wasted. A solution to these problems is an application of photoelectrocatalytic treatment methods, especially when they are coupled with energy generation. The paper presents a general overview of the semiconductor materials applied as photoelectrodes in the treatment of various pollutants. The fundamentals of photoelectrocatalytic reactions and the mechanism of pollutants treatment as well as parameters affecting the treatment process are presented. Examples of different semiconductor photoelectrodes that are applied in treatment processes are described in order to present the strengths and weaknesses of the photoelectrocatalytic treatment of industrial wastewater. This overview is an addition to the existing knowledge with a particular focus on the main experimental conditions employed in the photoelectrocatalytic degradation of various pollutants with the application of semiconductor photoelectrodes.

Study on the Preparation of WO3/TiO2 Composite Photocatalyst and its Photocatalytic Activity

2014 ◽  
Vol 540 ◽  
pp. 60-63
Author(s):  
Tian E Su ◽  
Chao Lin Miao
Keyword(s):  
Acetic Acid ◽  
Photocatalytic Activity ◽  
Sol Gel ◽  
Tetrabutyl Titanate ◽  
Gel Point ◽  
Doping Amount ◽  
Experimental Conditions ◽  
Composite Photocatalyst ◽  
Infrared Spectrometer ◽  
Ft Ir

WO3/TiO2 composite photocatalyst was prepared from tetrabutyl titanate, ammonium tungstate by sol-gel method. The influence of acetic acid and ethanol on the gel point time, and the influence of doping amount of W on the photocatalytic activity was studied. The properties of powders were characterized by Fourier transform infrared spectrometer(FT-IR), and the photocatalytic activity was characterized by probe reaction of methyl orange degradation. The results show that the homogeneous transparent precursor is prepared at the amount of acetic acid =1mL and the amount of ethanol =10mL.When the doping amount of W reached to 0.12%, the best photocatalysis efficiency was obtained. Under the experimental conditions, the infrared absorption band of the W－O was not observed.

scholarly journals Bismuth Oxyhalides for NOx Degradation under Visible Light: The Role of the Chloride Precursor

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 81
Author(s):  
Francesca Tessore ◽  
Federico Galli ◽  
Dalma Schieppati ◽  
Daria C. Boffito ◽  
Alessandro Di Michele ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photogenerated Electron ◽  
Green Technology ◽  
Bandgap Energy ◽  
Visible Radiation ◽  
Bismuth Nanoparticles ◽  
Metallic Bismuth ◽  
Bismuth Oxyhalides ◽  
The Impact

Photocatalysis is a green technology for tackling water and air contamination. A valid alternative to the most exploited photocatalytic material, TiO2, is bismuth oxyhalides, which feature a wider bandgap energy range and use visible radiation to attain photoexcitation. Moreover, their layered structure favors the separation of photogenerated electron–hole pairs, with an enhancement in photocatalytic activity. Controlled doping of bismuth oxyhalides with metallic bismuth nanoparticles allows for further boosting of the performance of the material. In the present work, we synthesized Y%Bi-doped BiO(Cl0.875Br0.125) (Y = 0.85, 1, 2, 10) photocatalysts, using cetyltrimethylammonium bromide as the bromide source and varying the chloride source to assess the impact that both length and branching of the hydrocarbon chain might have on the framing and layering of the material. A change in the amount of the reducing agent NaBH4 allowed tuning of the percentage of metallic bismuth. After a thorough characterization (XRPD, SEM, TEM, UV-DRS, XPS), the photocatalytic activity of the catalysts was tested in the degradation of NOx under visible light, reaching a remarkable 53% conversion after 3 h of illumination for the material prepared using cetylpyridinium chloride.

Impact of Al doping on a hydrothermally synthesized β-Ga2O3 nanostructure for photocatalysis applications

RSC Advances ◽  
2021 ◽  
Vol 11 (13) ◽  
pp. 7338-7346
Author(s):  
Sunjae Kim ◽  
Heejoong Ryou ◽  
In Gyu Lee ◽  
Myunghun Shin ◽  
Byung Jin Cho ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Grain Boundary ◽  
Redox Potential ◽  
Surface Area ◽  
Crystal Defect ◽  
Oxygen Defect ◽  
Al Doping ◽  
Photocatalytic Reactions

The photocatalytic activity is correlated with different parameters affecting the photocatalytic reactions; redox potential (RP), surface area (SA), crystal defect (CD), oxygen defect (OD), and grain-boundary induced defect (GD).

Visible light-driven novel g-C3N4/NiFe-LDH composite photocatalyst with enhanced photocatalytic activity towards water oxidation and reduction reaction

2015 ◽  
Vol 3 (36) ◽  
pp. 18622-18635 ◽  
Author(s):  
Susanginee Nayak ◽  
Lagnamayee Mohapatra ◽  
Kulamani Parida
Keyword(s):  
Photocatalytic Activity ◽  
Composite Materials ◽  
Visible Light ◽  
Water Splitting ◽  
Visible Light Irradiation ◽  
Water Oxidation ◽  
Reduction Reaction ◽  
Light Irradiation ◽  
Composite Photocatalyst ◽  
Visible Light Driven

Dispersion of exfoliated CN over the surface of exfoliated LDH composite materials, and its photocatalytic water splitting under visible-light irradiation.

Sign in / Sign up

Export Citation Format

Share Document