Chromium(VI) Reduction and Methyl Violet Degradation Using Light Harvesting Silver Nanoparticle Decorated at Polyoxovanadate-Reduced Graphene Oxide

Abstract

A novel ternary 0D/1D/2D nanocomposite of silver (Ag), polyoxovanadate (POV), and reduced graphene oxide (rGO) is synthesized using hydrothermal procedure. The synergistic structure of the composite material enhances the efficiency by combining the special qualities of 0D Ag NPs, 1D POV nanorods, and 2D rGO sheets. Herein, the photoreduction of chromium(VI) and the photodegradation of methyl violet (MV) dye are explored. The Ag/POV/rGO nanohybrid demonstrates superior photocatalytic performance compared to its individual components, 99.07% Cr(VI) reduction and 96.34% MV degradation under UV light due to efficient charge separation, extended light absorption, and increased surface area. The morphological study of the synthesized material revealed the Christian Cross architecture of POV decorated over reduced graphene oxide. The integration of Ag nanoparticles and POV nanorods onto rGO surface has been demonstrated to significantly improve the transfer and separation of photoinduced electrons and holes. Using density functional theory, calculations of Ag, bare POV, and Ag decorated POV cluster are systematically evaluated and an electromagnetic simulation is conducted using COMSOL Multiphysics software. Building on Mott-Schottky analysis and active species trapping experiments, the photocatalytic mechanism of Cr(VI) reduction and MV degradation is discussed. Additionally, the heterojunction is recyclable up to the fifth cycle.