• The reusability of this composite was confirmed by five successive recycling runs.
Fabrication of easily recyclable photocatalyst with excellent photocatalytic activity for degradation of organic pollutants in wastewater is highly desirable for practical application. In this study, a novel ternary magnetic photocatalyst BiVO4/Fe3O4/reduced graphene oxide (BiVO4/Fe3O4/rGO) was synthesized via a facile hydrothermal strategy. The BiVO4/Fe3O4 with 0.5 wt% of rGO (BiVO4/Fe3O4/0.5% rGO) exhibited superior activity, degrading greater than 99% Rhodamine B (RhB) after 120 min solar light radiation. The surface morphology and chemical composition of BiVO4/Fe3O4/rGO were studied by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV–visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The free radicals scavenging experiments demonstrated that hole (h+) and superoxide radical (O2•−) were the dominant species for RhB degradation over BiVO4/Fe3O4/rGO under solar light. The reusability of this composite catalyst was also investigated after five successive runs under an external magnetic field. The BiVO4/Fe3O4/rGO composite was easily separated, and the recycled catalyst retained high photocatalytic activity. This study demonstrates that catalyst BiVO4/Fe3O4/rGO possessed high dye removal efficiency in water treatment with excellent recyclability from water after use. The current study provides a possibility for more practical and sustainable photocatalytic process.
T Ahmed, H Zhang, Y Y Gao, H Xu, Y Zhang (2018). Surfactant-free synthesis of m-BiVO4 nanoribbons and enhanced visible-light photocatalytic properties. Materials Research Bulletin, 99: 298–305 https://doi.org/10.1016/j.materresbull.2017.11.029
2
R B N Baig, S Verma, R S Varma, M N Nadagouda (2016). Magnetic Fe@g-C3N4: A photoactive catalyst for the hydrogenation of alkenes and alkynes. ACS Sustainable Chemistry & Engineering, 4(3): 1661–1664 https://doi.org/10.1021/acssuschemeng.5b01610
3
N Bao, Z Yin, Q Zhang, S He, X Hu, X Miao (2016). Synthesis of flower-like monoclinic BiVO4/surface rough TiO2 ceramic fiber with heterostructures and its photocatalytic property. Ceramics International, 42(1 1, Part B): 1791–1800 https://doi.org/10.1016/j.ceramint.2015.09.142
4
M R U D Biswas, K Y Cho, J D Na, W C Oh (2019). Highly electro-conductive graphene-decorated PANI-BiVO4 polymer-semiconductor nanocomposite with outstanding photocatalytic performance. Materials Science and Engineering B, 251: 114469 https://doi.org/10.1016/j.mseb.2019.114469
5
S Chen, Y Yang, M Ji, W Liu (2011). Preparation, characterisation and activity evaluation of CaCO3/ZnO photocatalyst. Journal of Experimental Nanoscience, 6(3): 324–336 https://doi.org/10.1080/17458080.2010.509873
6
Y Chen, B Zhai, Y Liang (2019). Enhanced degradation performance of organic dyes removal by semiconductor/MOF/graphene oxide composites under visible light irradiation. Diamond and Related Materials, 98: 107508 https://doi.org/10.1016/j.diamond.2019.107508
7
S Dong, Y Cui, Y Wang, Y Li, L Hu, J Sun, J Sun (2014). Designing three-dimensional acicular sheaf shaped BiVO4/reduced graphene oxide composites for efficient sunlight-driven photocatalytic degradation of dye wastewater. Chemical Engineering Journal, 249: 102–110 https://doi.org/10.1016/j.cej.2014.03.071
8
X Feng, H Guo, K Patel, H Zhou, X Lou (2014). High performance, recoverable Fe3O4-ZnO nanoparticles for enhanced photocatalytic degradation of phenol. Chemical Engineering Journal, 244: 327–334 https://doi.org/10.1016/j.cej.2014.01.075
9
Z X Gan, X L Wu, M Meng, X B Zhu, L Yang, P K Chu (2014). Photothermal contribution to enhanced photocatalytic performance of graphene-based nanocomposites. ACS Nano, 8(9): 9304–9310 https://doi.org/10.1021/nn503249c
10
N Gao, Z Lu, X Zhao, Z Zhu, Y Wang, D Wang, Z Hua, C Li, P Huo, M Song (2016). Enhanced photocatalytic activity of a double conductive C/Fe3O4/Bi2O3 composite photocatalyst based on biomass. Chemical Engineering Journal, 304: 351–361 https://doi.org/10.1016/j.cej.2016.06.063
11
S Gao, C Guo, J Lv, Q Wang, Y Zhang, S Hou, J Gao, J Xu (2017). A novel 3D hollow magnetic Fe3O4/BiOI heterojunction with enhanced photocatalytic performance for bisphenol A degradation. Chemical Engineering Journal, 307: 1055–1065 https://doi.org/10.1016/j.cej.2016.09.032
12
G Hu, Z Zhang, Z Zhang, X Zhang, T Li (2021). Size and shape effects of MnFe2O4 nanoparticles as catalysts for reductive degradation of dye pollutants. Frontiers of Environmental Science & Engineering, 15(5): 108 https://doi.org/10.1007/s11783-021-1396-4
13
S Huang, J Zhao, C Wu, X Wang, S Fei, Q Zhang, Q Wang, Z Chen, K Uvdal, Z Hu (2019a). ZIF-assisted construction of magnetic multiple core-shell Fe3O4@ZnO@N-doped carbon composites for effective photocatalysis. Chemical Engineering Science, 209: 115185 https://doi.org/10.1016/j.ces.2019.115185
14
Y Huang, Z Guo, H Liu, S Zhang, P Wang, J Lu, Y Tong (2019b). Heterojunction architecture of N-doped WO3 nanobundles with Ce2S3 nanodots hybridized on a carbon textile enables a highly efficient flexible photocatalyst. Advanced Functional Materials, 29(45): 1903490 https://doi.org/10.1002/adfm.201903490
15
J Jiang, H Li, L Z Zhang (2012). New insight into daylight photocatalysis of AgBr@Ag: Synergistic effect between semiconductor photocatalysis and plasmonic photocatalysis. Chemistry (Weinheim an der Bergstrasse, Germany), 18(20): 6360–6369 https://doi.org/10.1002/chem.201102606
16
R Jiang, D Wu, G Lu, Z Yan, J Liu, R Zhou, M Nkoom (2019). Fabrication of Fe3O4 quantum dots modified BiOCl/BiVO4 p-n heterojunction to enhance photocatalytic activity for removing broad-spectrum antibiotics under visible light. Journal of the Taiwan Institute of Chemical Engineers, 96: 681–690 https://doi.org/10.1016/j.jtice.2019.01.010
17
J H Kim, J S Lee (2019). Elaborately modified BiVO4 photoanodes for solar water splitting. Advanced Materials, 31(20): 1806938 https://doi.org/10.1002/adma.201806938
18
K Li, X Lu, Y Zhang, K Liu, Y Huang, H Liu (2020a). Bi3TaO7/Ti3C2 heterojunctions for enhanced photocatalytic removal of water-borne contaminants. Environmental Research, 185: 109409 https://doi.org/10.1016/j.envres.2020.109409
19
W Li, R Yu, M Li, N Guo, H Yu, Y Yu (2019a). Photocatalytical degradation of diclofenac by Ag-BiOI-rGO: Kinetics, mechanisms and pathways. Chemosphere, 218: 966–973 https://doi.org/10.1016/j.chemosphere.2018.11.185
20
X Li, D Wei, L Ye, Z Li (2019b). Fabrication of Cu2O-RGO/BiVO4 nanocomposite for simultaneous photocatalytic CO2 reduction and benzyl alcohol oxidation under visible light. Inorganic Chemistry Communications, 104: 171–177 https://doi.org/10.1016/j.inoche.2019.04.012
21
Y Li, Y Xia, K Liu, K Ye, Q Wang, S Zhang, Y Huang, H Liu (2020b). Constructing Fe-MOF-derived Z-scheme photocatalysts with enhanced charge transport: Nanointerface and carbon sheath synergistic effect. ACS Applied Materials & Interfaces, 12(22): 25494–25502 https://doi.org/10.1021/acsami.0c06601
22
Y Li, X Y Xiao, Z H Ye (2018). Facile fabrication of tetragonal scheelite (t-s) BiVO4/g-C3N4 composites with enhanced photocatalytic performance. Ceramics International, 44(6): 7067–7076 https://doi.org/10.1016/j.ceramint.2018.01.143
23
Y Li, H Zhang, P Liu, D Wang, Y Li, H Zhao (2013). Cross-linked g-C3N4/rGO nanocomposites with tunable band structure and enhanced visible light photocatalytic activity. Small, 9(19): 3336–3344 https://doi.org/10.1002/smll.201203135
24
Y Luo, G Tan, G Dong, H Ren, A Xia (2016). A comprehensive investigation of tetragonal Gd-doped BiVO4 with enhanced photocatalytic performance under sun-light. Applied Surface Science, 364: 156–165 https://doi.org/10.1016/j.apsusc.2015.12.100
25
Y Luo, G Tan, G Dong, L Zhang, J Huang, W Yang, C Zhao, H Ren (2015). Structural transformation of Sm3+ doped BiVO4 with high photocatalytic activity under simulated sun-light. Applied Surface Science, 324: 505–511 https://doi.org/10.1016/j.apsusc.2014.10.168
26
Y X Ma, P Q La, W J Lei, C P Lu, X Y Du (2016). Adsorption of Hg (II) from aqueous solution using amino-functionalized graphite nanosheets decorated with Fe3O4 nanoparticles. Desalination and Water Treatment, 57(11): 5004–5012 https://doi.org/10.1080/19443994.2014.998292
27
A Malathi, J Madhavan, M Ashokkumar, P Arunachalam (2018). A review on BiVO4 photocatalyst: Activity enhancement methods for solar photocatalytic applications. Applied Catalysis A, General, 555: 47–74 https://doi.org/10.1016/j.apcata.2018.02.010
28
W Mao, L Zhang, T Wang, Y Bai, Y Guan (2021). Fabrication of highly efficient Bi2WO6/CuS composite for visible-light photocatalytic removal of organic pollutants and Cr(VI) from wastewater. Frontiers of Environmental Science & Engineering, 15(4): 52 https://doi.org/10.1007/s11783-020-1344-8
29
A Mclaren, T Valdes-Solis, G Li, S C Tsang (2009). Shape and size effects of ZnO nanocrystals on photocatalytic activity. Journal of the American Chemical Society, 131(35): 12540–12541 https://doi.org/10.1021/ja9052703
30
J Meng, J Pei, Z He, S Wu, Q Lin, X Wei, J Li, Z Zhang (2017). Facile synthesis of g-C3N4 nanosheets loaded with WO3 nanoparticles with enhanced photocatalytic performance under visible light irradiation. RSC Advances, 7(39): 24097–24104 https://doi.org/10.1039/C7RA02297B
31
X C Meng, Z Z Li, Z S Zhang (2018). Palladium nanoparticles and rGO co-modified BiVO4 with greatly improved visible light-induced photocatalytic activity. Chemosphere, 198: 1–12 https://doi.org/10.1016/j.chemosphere.2018.01.070
32
K Nakata, A Fujishima (2012). TiO2 photocatalysis: Design and applications. Journal of Photochemistry and Photobiology C, Photochemistry Reviews, 13(3): 169–189 https://doi.org/10.1016/j.jphotochemrev.2012.06.001
33
T D Nguyen-Phan, V H Pham, E W Shin, H D Pham, S Kim, J S Chung, E J Kim, S H Hur (2011). The role of graphene oxide content on the adsorption-enhanced photocatalysis of titanium dioxide/graphene oxide composites. Chemical Engineering Journal, 170(1): 226–232 https://doi.org/10.1016/j.cej.2011.03.060
34
S Nikam, S Joshi (2016). Irreversible phase transition in BiVO4 nanostructures synthesized by a polyol method and enhancement in photo degradation of methylene blue. RSC Advances, 6(109): 107463–107474 https://doi.org/10.1039/C6RA14700C
35
O Quiroz-Cardoso, S Oros Ruiz, A Solis Gomez, R Lopez, R Gomez (2019). Enhanced photocatalytic hydrogen production by CdS nanofibers modified with graphene oxide and nickel nanoparticles under visible light. Fuel, 237: 227–235 https://doi.org/10.1016/j.fuel.2018.10.013
36
X Ren, T Yan, D Wu, R Feng, Q Wei (2014). An excellent-responding ethanol sensor with quasi p-n heterojunction based on the composite material of Fe3O4 and Cu2O. Journal of Molecular Liquids, 198: 388–391 https://doi.org/10.1016/j.molliq.2014.07.040
37
A Roy, P Majumdar, P Sengupta, S Kundu, S Shinde, A Jha, K Pramanik, H Saha (2020). A photoelectrochemical supercapacitor based on a single BiVO4-RGO bilayer photocapacitive electrode. Electrochimica Acta, 329: 135170 https://doi.org/10.1016/j.electacta.2019.135170
38
D Sánchez-Martínez, D B Hernández Uresti, L M Torres Martinez, S Mejia-Rosales (2015). Photocatalytic properties of BiVO4 synthesized by microwave-assisted hydrothermal method under simulated sunlight irradiation. Research on Chemical Intermediates, 41(11): 8839–8854 https://doi.org/10.1007/s11164-015-1932-6
39
Y Sang, Z Zhao, J Tian, P Hao, H Jiang, H Liu, J P Claverie (2014). Enhanced photocatalytic property of reduced graphene oxide/TiO2 nanobelt surface heterostructures constructed by an in situ photochemical reduction method. Small, 10(18): 3775–3782 https://doi.org/10.1002/smll.201303489
40
L J Song, Y Y Pang, Y J Zheng, C F Chen, L Ge (2017). Design, preparation and enhanced photocatalytic activity of porous BiOCl/BiVO4 microspheres via a coprecipitation-hydrothermal method. Journal of Alloys and Compounds, 710: 375–382 https://doi.org/10.1016/j.jallcom.2017.03.283
41
S Stankovich, D A Dikin, G H B Dommett, K M Kohlhaas, E J Zimney, E A Stach, R D Piner, S B T Nguyen, R S Ruoff (2006). Graphene-based composite materials. Nature, 442(7100): 282–286 https://doi.org/10.1038/nature04969
42
S Stankovich, D A Dikin, R D Piner, K A Kohlhaas, A Kleinhammes, Y Jia, Y Wu, S T Nguyen, R S Ruoff (2007). Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide. Carbon, 45(7): 1558–1565 https://doi.org/10.1016/j.carbon.2007.02.034
43
J Tauc (1970). Absorption edge and internal electric fields in amorphous semiconductors. Materials Research Bulletin, 5(8): 721–729 https://doi.org/10.1016/0025-5408(70)90112-1
44
W Tu, Y Zhou, Z Zou (2013). Versatile graphene-promoting photocatalytic performance of semiconductors: basic principles, synthesis, solar energy conversion, and environmental applications. Advanced Functional Materials, 23(40): 4996–5008 https://doi.org/10.1002/adfm.201203547
45
J Wang, Y Song, J Hu, Y Li, Z Wang, P Yang, G Wang, Q Ma, Q Che, Y Dai, B Huang (2019). Photocatalytic hydrogen evolution on P-type tetragonal zircon BiVO4. Applied Catalysis B: Environmental, 251: 94–101 https://doi.org/10.1016/j.apcatb.2019.03.049
46
X J Wang, H L Liu, X L Wan, J R Wang, L L Chang (2013). Additive-free solvothermal synthesis of peanut-like BiVO4 powders with enhanced photocatalysis activity. Crystal Research and Technology, 48(12): 1066–1072 https://doi.org/10.1002/crat.201300198
47
X Xing, Y Ma, J Li, G Fan, H Ding, X Ma, L Yang, G Xi (2014). Facile one-pot synthesis and photocatalytic properties of hierarchically structural BiVO4 with different morphologies. CrystEngComm, 16(44): 10218–10226 https://doi.org/10.1039/C4CE01198H
48
S M Xiong, T H Wu, Z H Fan, D Q Zhao, M Du, X Xu (2017). Preparation of a leaf-like BiVO4-Reduced graphene oxide composite and its photocatalytic activity. Journal of Nanomaterials, 2017(12): 1–12 https://doi.org/10.1155/2017/3475248
49
Y Yan, T Ni, J Du, L Li, S Fu, K Li, J Zhou (2018). Green synthesis of balsam pear-shaped BiVO4/BiPO4 nanocomposite for degradation of organic dye and antibiotic metronidazole. Dalton Transactions (Cambridge, England), 47(17): 6089–6101 https://doi.org/10.1039/C8DT00408K
50
R Yang, Z Zhu, C Hu, S Zhong, L Zhang, B Liu, W Wang (2020). One-step preparation (3D/2D/2D) BiVO4/FeVO4@rGO heterojunction composite photocatalyst for the removal of tetracycline and hexavalent chromium ions in water. Chemical Engineering Journal, 390: 124522 https://doi.org/10.1016/j.cej.2020.124522
51
J Yu, A Kudo (2006). Effects of structural variation on the photocatalytic performance of hydrothermally synthesized BiVO4. Advanced Functional Materials, 16(16): 2163–2169 https://doi.org/10.1002/adfm.200500799
52
J Zeng, J Zhong, J Li (2017). Fabrication of CdS modified BiVO4 with enhanced sunlight photocatalytic performance. Inor. Inorganic and Nano-Metal Chemistry, 47(12): 1728–1732 https://doi.org/10.1080/24701556.2017.1357624
53
J Zeng, J Zhong, J Li, Z Xiang, X Liu, J Chen (2014). Improvement of photocatalytic activity under solar light of BiVO4 microcrystals synthesized by surfactant-assisted hydrothermal method. Materials Science in Semiconductor Processing, 27: 41–46 https://doi.org/10.1016/j.mssp.2014.06.014
54
G C Zhang, J L Zhong, M Xu, Y Yang, Y Li, Z X Fang, S F Tang, D L Yuan, B Wen, J M Gu (2019a). Ternary BiVO4/NiS/Au nanocomposites with efficient charge separations for enhanced visible light photocatalytic performance. Chemical Engineering Journal, 375: 122093 https://doi.org/10.1016/j.cej.2019.122093
55
M Zhang, J L Gong, G M Zeng, P Zhang, B Song, W C Cao, H Y Liu, Y Huan (2018). Enhanced degradation performance of organic dyes removal by bismuth vanadate-reduced graphene oxide composites under visible light radiation. Colloids and Surfaces a-Physicochemical and Engineering Aspects, 559: 169–183
56
W Zhang, Y Sun, F Dong, W Zhang, S Duan, Q Zhang (2014). Facile synthesis of organic–inorganic layered nanojunctions of g-C3N4/(BIO)2CO3 as efficient visible light photocatalyst. Dalton Transections, 43(31): 12026–12036 https://doi.org/10.1039/C4DT00513A
57
W Zhang, M Wang, W Zhao, B Wang (2013). Magnetic composite photocatalyst ZnFe2O4/BiVO4: Synthesis, characterization, and visible-light photocatalytic activity. Dalton Transactions (Cambridge, England), 42(43): 15464–15474 https://doi.org/10.1039/c3dt52068d
58
X Zhang, J Zhang, J Yu, Y Zhang, L Yu F, Jia, Y Tan, Y Zhu, B Hou (2019). Enhancement in the photocatalytic antifouling efficiency over cherimoya-like InVO4/BiVO4 with a new vanadium source. Journal of Colloid and Interface Science, 533: 358–368 https://doi.org/10.1016/j.jcis.2018.06.090
59
R Zhu, F Tian, R Yang, J He, J Zhong, B Chen (2019). Z scheme system ZnIn2S4/RGO/BiVO4 for hydrogen generation from water splitting and simultaneous degradation of organic pollutants under visible light. Renewable Energry, 139(AUG): 22–27 https://doi.org/10.1016/j.renene.2019.02.049
60
W Y Zhu, F Q Sun, R Goei, Y Zhou (2017). Facile fabrication of RGO-WO3 composites for effective visible light photocatalytic degradation of sulfamethoxazole. Applied Catalysis B: Environmental, 207: 93–102 https://doi.org/10.1016/j.apcatb.2017.02.012
