Lead bismuth oxybromide/graphene oxide: Synthesis, characterization, and photocatalytic activity for removal of carbon dioxide, crystal violet dye, and 2-hydroxybenzoic acid

A novel lead bismuth oxybromide/graphene oxide (PbBiO2Br/GO) composite photocatalyst were prepared using a controlled and nontemplate hydrothermal technique with PbBiO2Br and GO as the starting material. The heterojunction photocatalysts were characterized through XRD, FE-SEM-EDS, HR-TEM, XPS, DR-UV-vis, BET, PL, EPR, and UPS. Under the optimal synthesis conditions, the photocatalytic activity of PbBiO2Br/GO composites was much higher than that of PbBiO2Br. Under 25 degrees C, 1 atm, and 432-nm visible light irradiation at, the optimized PbBiO2Br/GO increased the rate (at 1.913 mu mol g(-1) h(-1)) of photocatalytic conversion from carbon dioxide (CO2) to methane (CH4). This conversion rate was higher than that of the original PbBiO2Br material (0.957 mu mol g(-1) h(-1)). Therefore, PbBiO2Br/GO is superior for CH4 production and has great potential as CO2 photoreduction catalysts. In addition, such catalytic performance (when using 0.05 wt%-GO/PbBiO2Br composite as a photocatalyst) indicates that the optimal reaction rate constants of crystal violet (CV) and 2-hydroxybenzoic acid (2-HBA) are 0.1278 and 0.0093 h(-1), respectively, which are 1.82 and 1.24 times the reaction rate constant of PbBiO2Br as a photocatalyst, respectively. Our findings are useful for PbBiO2Br/GO synthesis and in its future environmental applications, particularly in solar fuel manufacture. (C) 2019 Elsevier Inc. All rights reserved.