High-efficient TiO₂ NRs/BiOI NSs heterojunction photoanodes for photoelectrochemical water splitting

Abstract

In this article, we report the preparation of a novel 1D/2D TiO₂ NRs/BiOI NSs photoanode via a simple hydrothermal method followed by SILAR method. This facile synthesis route can simultaneously achieve uniform TiO₂ NRs/BiOI NSs composite nanostructures and obtain varied thick of BiOI NSs by controlling the SILAR cycles. The TiO₂ NRs/BiOI-3 (SILAR cycles of 15 cycles) heterojunction photoanode enhanced highest photocatalytic activity with a photocurrent density of 0·40 mA cm^–2 at 1·23 V versus RHE compared to pristine TiO₂ NRs photoanode at the same condition. It is demonstrated that the presence of BiOI NSs has played an important role in expanding the spectral response region and reduced photogenerated charges recombination rate. More importantly, the results provide new insights in the 1D/2D NRs/NSs composite structure served as photoanodes for PEC water splitting.

Keywords:

• TiO₂
• BiOI
• heterojunction
• photoelectrochemical water splitting

Acknowledgments

The authors gratefully acknowledge financial support from Scientific & Technological Innovation Project of Xinxiang University.