Highly visible-light-responsive Cu₂O/rGO decorated with Fe₃O₄@SiO₂ nanoparticles as a magnetically recyclable photocatalyst

Abstract

The rhombic dodecahedral cuprous oxide-reduced graphene oxide/core-shell FeO@SiO composites (denoted as rCuO-rGO/FeO@SiO) are successfully synthesized facilely via a wet-chemical route. The resulting rCuO-rGO/FeO@SiO combines the unique structure of CuO, electronic characteristics of reduced graphene oxide (rGO) and magnetic property of FeO@SiO to be an effective and recoverable photocatalyst for the degradation of methyl orange (MO). The obtained results show that rCuO-rGO/FeO@SiO is capable of completely degrading MO in the presence of a very low catalyst concentration (0.125 g l) within a short time (60 min) under visible light compared to the reported catalysts. The observations may be due to the distinctive interfacial structures of rhombic dodecahedral CuO nanoparticles connected to rGO sheets that can enhance the separation of photogenerated electron-hole pairs, stabilize the CuO and increase MO adsorption, as evidenced by a variety of spectroscopic analyses (transmission electron microscopy, x-ray photoelectron spectroscopy and photoluminescence). More importantly, these efficient photocatalysts can easily be recovered under a magnetic field and remain highly photoactive towards the degradation of MO after cyclic tests, and may be promising photocatalysts for practical applications in the solar-energy purification of wastewater.

Dynamic growth of rhombic dodecahedral Cu2O crystals controlled by reaction temperature and their size-dependent photocatalytic performance

“…1 Various experiments regarding visible-light photodegradation of different categories of organic dyes have been reported. 2 Cuprous oxide (Cu 2 O) 3,4 and its complexes (such as heterostructures [5][6][7][8][9] and plasmonic [10][11][12][13] forms) represent important visible-light photocatalysts, and have been widely applied in photocatalytic degradation of organic pollutants.…”

3D laminated graphitic carbon nitride decorating with 2D / 2D Bi 2 WO 6 / rGO nanosheets for selective photoreduction of CO 2 to CO

“…31 Also, the decoration of 2D sp 2 -structured reduced graphene oxide (rGO) with high charge mobility into heterojunction can further hinder the electron-hole recombination. 36,37 In this work, a microwave-assisted hydrothermal route is used to prepare Bi 2 WO 6 /rGO/3D-GCN with 2D/2D/3D heterojunction. The prepared photocatalysts are thoroughly characterized by a series of spectroscopies and analytical tools.…”

“…Among the aforementioned heterojuncted components, the 2D Bi 2 WO 6 is one of promising semiconductors which exhibit unique properties such as high chemical stability, narrow band gap, and suitable conduction and valance band potentials for the heterojunction with GCN 31 . Also, the decoration of 2D sp 2 ‐structured reduced graphene oxide (rGO) with high charge mobility into heterojunction can further hinder the electron‐hole recombination 36,37 …”

Effect of bandgap alignment on the photoreduction of CO2 into methane based on Cu2O-decorated CuO microspheres

“…Zhou et al [10] reported that Cu 2 O@Cu nanorods had a good photocatalytic activity for CO 2 reduction into solar fuels under visible light irradiation. Cu 2 O and CuO decorated with reduced graphene oxide exhibited an improved catalytic activities [15,16], which were explained as the decreased energy barrier for the transfer of photogenerated electrons to the surface. And N doped CuO-TiO 2 photocatalysts under UVA lamp irradiation in gas phase CO 2 reduction exhibited a maximal conversion of CO 2 to CH 4 with a value of 0.14 µmol CH 4 /g [17].…”