One-Step Hydrothermal Synthesis of Sn-Doped SbSe for Solar Hydrogen Production.

Antimony selenide (SbSe) has recently been intensively investigated and has achieved significant advancement in photoelectrochemical (PEC) water splitting. In this work, a facile one-step hydrothermal method for the preparation of Sn-doped SbSe photocathodes with improved PEC performance was investigated. We present an in-depth study of the performance enhancement in Sn-doped SbSe photocathodes using capacitance-voltage (CV), drive-level capacitance profiling (DLCP), and electrochemical impedance spectroscopy (EIS) techniques. The incorporation of Sn into the SbSe results in increased carrier density, reduced surface defects, and improved charge separation, thereby leading to improved PEC performance. With a thin SbSe absorber layer (270 nm thickness), the Sn-doped SbSe photocathode exhibits an improved photocurrent density of 17.1 mA cm at 0 V versus RHE ( ) compared to that of the undoped SbSe photocathode (14.4 mA cm). This work not only highlights the positive influence of Sn doping on SbSe photocathodes but also showcases a one-step method to synthesize doped SbSe with improved optoelectronic properties.