Enhanced photocatalytic activity of biogenically synthesized CuO nanostructures against Xylenol orange and rhodamine B dyes

Aims: In the present study, we investigate the photocatalytic properties of α-Ag2WO4 nanocrystals-modified Palygorskite (PAL) clay synthesized by the impregnation method. The PAL clay was chemically purified and heat-treated (500 ºC for 2 h), which served as an excellent supporting matrix for loading α-Ag2WO4(α-AWO) nanocrystals. Background: Water contamination is one of the most serious problems affecting human health, ecosystem survival, and the economic growth of societies. Industrial effluents, such as textile dyes, when not treated and improperly discharged into water resources are considered the main cause of water pollution. Thus the scientific community has been developing effective remediation technologies based on advanced oxidative processes to reduce the harmful effects of these organic pollutants. Objective: Improve the photocatalytic activity of PAL clay with α-AWO nanocrystals to degradation of Rhodamine B (RhB) dye. Methods: We purify and heat-treated the PAL clay, synthesize nanocrystals ofα-AWO nanocrystals and modify PAL clay with 30% α-AWO nanocrystals by the impregnation method. The modified PAL clay was able to improve RhB dye degradation. The materials were characterized by XRD, RAMAN,FE-SEM, FT-IR, XRF, etc. The samples were used as photocatalysts under UV-C lamps for the degradation of RhB dye in order to analyze its catalytic performances. Results: ThePAL clay modified with 30% α-AWO nanocrystals showed a catalytic efficiency of 79%, and degradation kinetics about 16 times higher when compared to PAL-500 only purified and heat-treated at 500 ºC. In this way, this PAL-modified is an alternative as a low-cost photocatalyst for the degradation of RhB dye. Conclusion: Ultraviolet-Visiblespectra revealed that our materials have opticalband gap energies controlled by indirect and direct electronic transitions and suitable to be activated under ultraviolet illumination. The adequate amount (30 wt.%) of α-Ag2WO4 nanocrystals added to PAL brought significant improvement of photocatalytic activity for the degradation of rhodamine B. Finally, a photocatalytic mechanism was proposed in detail.

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The effects of solvent viscosity on the morphology and photocatalytic activity of BiOBr catalysts

Functional Materials Letters ◽

10.1142/s1793604721430062 ◽

2021 ◽

Author(s):

Fengjuan Ge ◽

Jie Zhu ◽

Yan Xu ◽

Jing Li ◽

Xueyang Zhang

Keyword(s):

Photocatalytic Activity ◽

Surface Area ◽

Rhodamine B ◽

Synthesis Method ◽

Degradation Process ◽

High Viscosity ◽

Precipitation Method ◽

Glycerol Solution ◽

Solvent Viscosity ◽

Degradation Tests

BiOBr photocatalysts were prepared by changing the solvent and synthesis method. SEM, XRD and BET characterization shows that the sample prepared in high-viscosity solution by precipitation method has tremella-like microstructure, with smaller size and higher surface area. Among them, the BiOBr prepared in glycerol solution (GR-P) has the highest surface area of 113.8 m2⋅[Formula: see text]. XRD also indicates that the GR-P has much more exposed (110) facets than other samples. The Rhodamine B degradation tests show that the GR-P has the best activity on both deethylation and aromatic ring destruction steps, indicating that the exposed (110) facets promote the degradation process.

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Novel heterostructured Bi2S3/Bi2Sn2O7 with highly visible light photocatalytic activity for the removal of rhodamine B

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2015.01.040 ◽

2015 ◽

Vol 154 ◽

pp. 30-37 ◽

Cited By ~ 43

Author(s):

Weicheng Xu ◽

Jianzhang Fang ◽

Yunfang Chen ◽

Shaoyou Lu ◽

Guangying Zhou ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Rhodamine B ◽

Visible Light Photocatalytic Activity ◽

Visible Light Photocatalytic

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Copper oxide supported on graphene for phodegradation of rhodamine B

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v11n4.391 ◽

2015 ◽

Vol 11 (4) ◽

Cited By ~ 1

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.

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