Ce Doped V2O5 nanoparticles for dual functionality: Photocatalytic degradation of organic dye and supercapacitor applications

Our study aims to synthesize undoped vanadium pentoxide (V2O5) and rare earth element cerium (Ce) doped V2O5 nanoparticles through ultrasonic-assisted synthesis to manufacture efficient photocatalysts and supercapacitor electrodes for first time. XRD analysis confirms that the orthorhombic crystal phase of both V2O5 nanoparticles represents the incorporation of Ce4+ ion into the V2O5 crystal structure by substitution and average crystalline sizes around 22-30 nm. Among the samples, Ce-doped V2O5 nanoparticles exhibited excellent photocatalytic activity by degrading 92 % of the rhodamine B (RhB) dye within 60 min under visible light irradiation. Ce-doped V2O5 revealed superior performance compared to V2O5 nanoparticles (190.9 F g- 1) on the basis of specific capacitance (Cs) values (321.9 F g- 1) at a current density of 1 A g- 1. The capacitance stability of the designed electrode was 95.2 % after 5000 cycles, as predicted. Additionally, novelty of preset work is a density functional theory (DFT) based simulation indicated that the doping of Ce reduced the V2O5 band gap by forming shallow doping states close to the valence and conduction energy bands. The existence of shallow dopant states and the band gap decrease promote effective charge separation and better photon adsorption of Ce-doped V2O5, which ends up with improved photocatalytic activity. Our finding suggests the improvement in catalytic and electrochemical efficacy is attributed to dopant ions affecting the recombination process of the electron-hole pairs produced by the photon absorption.