Tailoring WO3 photoelectrodes with defect-rich MoO3-x nanosheets for efficient water splitting reaction
Abstract: Despite its potential for photochemical and photoelectrochemical applications, tungsten trioxide (WO3) presents limitations due to its wide bandgap and rapid charge carrier recombination. Here, the photoelectrochemical performance of WO3 films were enhanced by incorporating defect-rich MoO3-x nanosheets. The WO3 films were produced using a simple polymer-assisted deposition (PAD) method and subsequently modified with defect-rich MoO3-x nanosheets, prepared via solvothermal synthesis, by drop-casting. Electronic microscopy revealed that WO3 exhibited an agglomerated nano-globular structure with several fissures where the MoO3-x nanosheets were anchored. In terms of photoelectrochemical performance, the optimal WO3/MoO3-x film exhibited photocurrent densities of 1.30 ± 0.12 mA cm−2 and 3.20 ± 0.2 mA cm−2 under solar simulator and LED 427 nm illumination, respectively, doubling the photocurrent density of bare WO3. This enhanced performance was attributed to the formation of a type II heterojunction, which facilitates more efficient charge carrier separation and due to the catalytic enhancement for the oxygen evolution reaction provided by MoO3-x.
Author(s): Hugo L. S. Santos, Leticia S. Bezerra, Pedro H. C. Camargo & Lucia H. Mascaro
Journal of Solid State Electrochemistry
Published: 26 March 2025
