Increased Photoelectrochemical Performance of Vanadium Oxide Thin Film by Helium Plasma Treatment with Auxiliary Molybdenum Deposition

Abstract

Helium (He) plasma treatment can be a versatile tool to fabricate nanostructures on a surface and change the surface chemistry. Herein, vanadium (V) thin film is exposed to helium plasmas and the changes in morphology and surface properties are investigated. The irradiation condition at which the surface morphology can be changed is identified. During the He plasma irradiation, molybdenum (Mo) from the sample cover deposits and formation of composite nanostructured photoelectrode with a combination of occurs. The photoelectrochemical (PEC) performance increases threefold through the plasma treatment. In addition to the increase in the surface area, the formation of the heterogenous/composite structure, oxygen vacancies, and reduced oxides such as decreases the charge‐transfer resistance and contributes to the improvement in the PEC performance.