Cerium Vanadate with Nitrogen Doped Reduced Graphene Oxide for Visible Light‐Driven Hydrogen Evolution and Dye Degradation

Abstract

The present work deals with precipitation followed by the hydrothermal method for the synthesis of cerium vanadate decorated nitrogen doped reduced graphene oxide (CeV/NRGO) nanocomposite. The crystallographic and Raman spectroscopic characterization confirm the formation of CeV/NRGO nanocomposite. A computational study on crystal structure using Material Studio, confirms the presence of zircon‐like CeV with VO4 tetrahedra sharing corners and edges with CeO8 dodecahedra in CeV/NRGO nanocomposite. X‐ray photoelectron spectroscopic (XPS) analysis supports the presence of Ce in +3 and +4 oxidation state. The optical characterization shows the decreased bandgap in CeV/NRGO nanocomposite (2.03 eV) compared to pristine CeV (2.35 eV). Enhanced photocatalytic activity is observed towards hydrogen evolution in CeV/NRGO (15 124 μmol) compared to CeV (7215 μmol) and NRGO (2034 μmol). In addition, CeV/NRGO, CeV, and NRGO are evaluated for degradation of Alizarin Yellow (AY) and Orange G (OG) dyes in presence of visible light. CeV/NRGO managed to degrade 97% and 94% of AY and OG, respectively in 80 min. The electron spin resonance (ESR) studies show superoxide radicals and hydroxyl ions are the active species responsible for photocatalytic reactions. Based on the liquid chromatography–mass spectroscopy (LC–MS) results, a possible photocatalytic mechanism has been discussed. The good stability and reusability of CeV/NRGO nanocomposite could be a choice of material for energy and environmental related research.