Ag and BiVO4 decorated reduced graphene oxide: A potential nano hybrid material for photocatalytic, sensing and biomedical applications

Abstract

Recently, the development of multifunctional heterostructured nanocomposites has recieved significant interest due to their numerous applications. In this study, BiVO4, Ag-BiVO4 and Ag-BiVO4-rGO photocatalysts were synthesised using Citrus bergamia through solution combustion technique. Prepared nanomaterials were characterized by PXRD, FTIR, Raman, UV– visible DRS, TEM, SEM and EDX spectroscopy studies. The materials were assessed for photocatalytic MB dye degradation. Ag-BiVO4-rGO photocatalyst was found to degrade MB dye completely in 60 min whereas BiVO4 and Ag-BiVO4 NPs degraded the dye in 150 and 180 min respectively. Photoluminescence spectra evidenced the efficient charge separation in Ag-BiVO4-rGO composite compared to BiVO4 and Ag-BiVO4 NPs. The electrochemical nitrite sensing studies revealed that Ag-BiVO4-rGO composite was a promising electrocatalyst with a significant anodic peak current 57.43 μA at the potential of 0.867 V. The limit of detection of nitrate was observed to be 8.7517 μM. Further, the composite material exhibited better biological activities such as antioxidant, erythrocytes lysis, anticoagulant, anti-platelet and antibacterial properties. The superior properties of Ag-BiVO4-rGO are ascribed to reduction in the energy gap as well as crystallite size by incorporation of Ag into the crystal lattice and presence of rGO. The present study demonstrates a novel approach to develop multifunctional Ag-BiVO4-rGO nano hybrid material for photocatalytic dye degradation, photoluminescence, electrocatalytic nitrite detection and selected biomedical applications.