Constructing semiconductor heterojunction with optimal structure and composition is highly desired to maximize the solar light utilization for photoelectrochemical (PEC) water splitting. Here, we reported the fabrication of BiVO 4 @ZnO heterojunction with a novel nanostructure for PEC water splitting via foaming-assisted electrospinning and subsequent atomic layer deposition (ALD) techniques. In such BiVO 4 @ZnO heterojunction, the isolated BiVO 4 nanoparticles were packaged within the ZnO microbelt matrix. During PEC water splitting, the BiVO 4 acts as the primary light absorber for wider solar spectral harvesting, and the ZnO prompts the transfer of the photo-excited high-energy electrons, which would render them with prolonged lifetime and enhanced separation of the photogenerated charge carriers. In addition, the microbelts architecture with a hollow channel can also effectively improve the interfacial charge separation and transportation. Accordingly, the PEC performances of BiVO 4 @ZnO hybrid microbelts were significantly enhanced with a photocurrent density up to ∼0.46 mA cm −2 (at 1.23 V vs. reversible hydrogen electrode (RHE) under simulated sunlight illumination), which is 15.3 times to that of pure BiVO 4 counterpart (∼0.03 mA cm −2 ). The photocurrent density of the BiVO 4 @ZnO electrode can be further increased to 1.07 mA cm −2 at 1.2 V vs. RHE by adding hole scavenger (NaSO 3 ) in the electrolyte solution under AM 1.5 G irradiation.
- BiVO @ZnO heterojunction
- Photoelectrochemical hydrogen production
ASJC Scopus subject areas
- Chemical Engineering(all)