Abstract

BiVO4 is regarded as a promising photoanode material because of its narrow band gap (∼ 2.4 eV). However, the poor bulk carrier transport capacity severely limits the actual performance of BiVO4 in photoelectrochemistry (PEC) water splitting. Here, we tried to synthesize two-dimensional (2D) morphology by adding structure-directing agents to hydrothermal solution and introduce oxygen vacancies by photoassisted self-reduction. In the scheme, the 2D morphology can shorten the carrier diffusion length and the construction of oxygen vacancies can increase the bulk carrier concentration. Through the combined effect of both, the inherent poor carrier transport capacity of BiVO4 has been improved, which has been proven by Electrochemical Impedance Spectroscopy (EIS), Intensity Modulated Photocurrent Spectroscopy (IMPS) and Mott-Schottky (M-S) plots. At 1.23 V vs. RHE, the photocurrent density increases from ∼1.60 mA/cm2 (2D BiVO4) to ∼2.30 mA/cm2 [2D BiVO4(Vox)], which is 8 times larger than that of bare BiVO4(0.3 mA/cm2). The incident photon-to-current efficiencies (IPCE) of 2D BiVO4(Vox) have reached the value of 46% (at 350 nm). The carrier separation efficiency (ƞsep) and carrier injection efficiency (ƞinj) have been improved up to 49% and 68%, respectively.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.