Novel Preparation of Bi/BiVO4 Catalyst Supported by Alkali-Modified Diatomite and its Visible Light-Driven Degradation Performance

NANO ◽  
2021 ◽  
pp. 2150034
Author(s):  
Mingwei Liu ◽  
Linhua Jiang ◽  
Mingxia Shen ◽  
Mingzhi Guo ◽  
Pengfei Zhu ◽  
...  

The manufacture of diatomite-supported composite catalyst with enhanced photocatalytic activity is of great interest for wastewater treatment. In this study, the pretreated diatomite (PD) with 5[Formula: see text]wt.% NaOH solution possessed better pore structure and large specific surface area. A facile hydrothermal-photoreduction method was adopted to prepare Bi/BiVO4/PD composite. The chemical composition, microstructure morphology and pore structure of samples were investigated by means of XRF, XRD, SEM, TEM, EDS, XPS and BET methods. The results showed that the metallic Bi was uniformly deposited on the BiVO4. After loaded on PD, both surface area and total pore volume had a significant increase. In addition, UV-vis diffuse reflectance spectra presented that the absorption capacity of Bi/BiVO4/PD-25% composite in the visible light range was remarkably high due to the surface plasmon resonance (SPR) caused by metallic Bi. From photoluminescence (PL) spectra and transient photocurrents, the heterojunction formed between Bi/BiVO4 and PD helped promoting the separation and migration of photo-generated carriers, which in turn led to higher photocatalytic activity. Compared with Bi/BiVO4, Bi/BiVO4/PD loaded with 25[Formula: see text]wt.% PD showed highest decolorization rate for rhodamine B (RhB), malachite green (MG), methylene blue (MB), methyl orange (MO) and lemon yellow (LY) under visible light irradiation. According to trapping experiments on free radicals, the active species that played a decisive role in RhB degradation were h[Formula: see text] and [Formula: see text]. Findings from this study suggest that Bi/BiVO4/PD-25% composite holds great promise for dye degradation and wastewater treatment.

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3948
Author(s):  
Lingfang Qiu ◽  
Zhiwei Zhou ◽  
Mengfan Ma ◽  
Ping Li ◽  
Jinyong Lu ◽  
...  

Novel visible-light responded aluminosilicophosphate-5 (SAPO-5)/g-C3N4 composite has been easily constructed by thermal polymerization for the mixture of SAPO-5, NH4Cl, and dicyandiamide. The photocatalytic activity of SAPO-5/g-C3N4 is evaluated by degrading RhB (30 mg/L) under visible light illumination (λ > 420 nm). The effects of SAPO-5 incorporation proportion and initial RhB concentration on the photocatalytic performance have been discussed in detail. The optimized SAPO-5/g-C3N4 composite shows promising degradation efficiency which is 40.6% higher than that of pure g-C3N4. The degradation rate improves from 0.007 min−1 to 0.022 min−1, which is a comparable photocatalytic performance compared with other g-C3N4-based heterojunctions for dye degradation. The migration of photo-induced electrons from g-C3N4 to the Al site of SAPO-5 should promote the photo-induced electron-hole pairs separation rate of g-C3N4 efficiently. Furthermore, the redox reactions for RhB degradation occur on the photo-induced holes in the g-C3N4 and Al sites in SAPO-5, respectively. This achievement not only improves the photocatalytic activity of g-C3N4 efficiently, but also broadens the application of SAPOs in the photocatalytic field.


2020 ◽  
Vol 20 (9) ◽  
pp. 5426-5432
Author(s):  
G. Gnanamoorthy ◽  
M. Muthukumaran ◽  
P. Varun Prasath ◽  
V. Karthikeyan ◽  
V. Narayanan ◽  
...  

Photocatalysts provide excellent potential for the full removal of organic chemical pollutants as an environmentally friendly technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. The Sn6SiO8/rGO nanocomposite was synthesized by a hydrothermal method. The Sn6SiO8 nanoparticles hexagonal phase was confirmed by XRD and functional groups were analyzed by FT-IR spectroscopy. The bandgap of Sn6SiO8 nanoparticles (NPs) and Sn6SiO8/GO composites were found to be 2.7 eV and 2.5 eV, respectively. SEM images of samples showed that the flakes like morphology. This Sn6SiO8/rGO nanocomposite was testing for photocatalytic dye degradation of MG under visible light illumination and excellent response for the catalysts. The enhancement of photocatalytic performance was mainly attributed to the increased light absorption, charge separation efficiency and specific surface area, proved by UV-vis DRS. Further, the radical trapping experiments revealed that holes (h+) and superoxide radicals (·O−2) were the main active species for the degradation of MG, and a possible photocatalytic mechanism was discussed.


2011 ◽  
Vol 335-336 ◽  
pp. 1385-1390 ◽  
Author(s):  
Shuo Wiei Zhao ◽  
Hui Xu ◽  
Hua Ming Li ◽  
Yuan Guo Xu

In order to improve the photocatalytic activity, Co was successfully loaded into Ag3VO4 by using impregnation process. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). The XRD and SEM–EDS analyses revealed that Co ion was dispersed on Ag3VO4. The DRS results indicated that the absorption edge of the Co–Ag3VO4 catalyst shifted to longer wavelength. The enhanced photocatalytic activity of Co–Ag3VO4 for Methylene Blue(MB) dye degradation under visible light irradiation was due to its wider absorption edge and higher separation rate of photo-generated electron and holes. In the experimental conditions, it is demonstrated that the MB was effectively degraded by more than 95% within 40 min when the Co–Ag3VO4 catalyst was calcined at 300°C with 1 wt.% Co content.


2016 ◽  
Vol 45 (43) ◽  
pp. 17521-17529 ◽  
Author(s):  
Shuai-Ru Zhu ◽  
Peng-Fei Liu ◽  
Meng-Ke Wu ◽  
Wen-Na Zhao ◽  
Guo-Chang Li ◽  
...  

BiOBr/NH2-MIL-125(Ti) composite photocatalysts have been prepared by incorporating NH2-MIL-125(Ti) with BiOBr and exhibited improved photocatalytic activity under visible light compared to pristine BiOBr and NH2-MIL-125(Ti).


NANO ◽  
2018 ◽  
Vol 13 (11) ◽  
pp. 1850129 ◽  
Author(s):  
Chujun Chen ◽  
Xia Xin ◽  
Jinniu Zhang ◽  
Gang Li ◽  
Yafeng Zhang ◽  
...  

To improve the high charge carrier recombination rate and low visible light absorption of {001} facets exposed TiO2 [TiO2(001)] nanosheets, few-layered MoS2 nanoparticles were loaded on the surfaces of TiO2(001) nanosheets by a simple photodeposition method. The photocatalytic activities towards Rhodamine B (RhB) were investigated. The results showed that the MoS2–TiO2(001) nanocomposites exhibited much enhanced photocatalytic activities compared with the pure TiO2(001) nanosheets. At an optimal Mo/Ti molar ratio of 25%, the MoS2–TiO2(001) nanocomposites displayed the highest photocatalytic activity, which took only 30[Formula: see text]min to degrade 50[Formula: see text]mL of RhB (50[Formula: see text]mg/L). The active species in the degradation reaction were determined to be h[Formula: see text] and [Formula: see text]OH according to the free radical trapping experiments. The reduced charge carrier recombination rate, enhanced visible light utilization and increased surface areas contributed to the enhanced photocatalytic performances of the 25% MoS2–TiO2(001) nanocomposites.


RSC Advances ◽  
2019 ◽  
Vol 9 (16) ◽  
pp. 8977-8993 ◽  
Author(s):  
Ruchika Tanwar ◽  
Uttam Kumar Mandal

The photocatalytic activity of BiOCl is tuned through heterogeneous decoration with an integrated Ni0.5Zn0.5Fe2O4@polyaniline. The outstanding degradation capacity, effects of parameters on degradation kinetics and a kinetic model using regression analysis is reported.


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