Construction of 1D/2D Sb₂(S,Se)₃/In₂S₃ S-Scheme Heterojunction Photoanodes toward Photoelectrochemical Water Splitting

Antimony sulfoselenide (Sb 2 (S,Se) 3 ), a highly promising photovoltaic material, has garnered significant attention in solar cell applications. Sb 2 (S,Se) 3 exhibits anisotropic carrier transport, with carrier mobility along the [ hk 1] direction being significantly higher than that along the [ hk 0] direction. In this work, [ hk 1]-oriented Sb 2 (S,Se) 3 nanorods were epitaxially grown on 2D Bi 2 O 2 S nanosheets via a one-step hydrothermal method. Subsequently, an S-scheme heterojunction was constructed by integrating In 2 S 3 . This heterojunction not only compensates for the weak short-wavelength light absorption of the photoanode but also suppresses carrier recombination. Achieving 6.05 mA cm –2 at 1.23 V RHE, the composite photoanode confirms enhanced PEC performance through efficient carrier utilization. This work develops a hydrothermal methodology to synthesize quasi-1D Sb 2 (S,Se) 3 nanorods and construct 1D–2D Sb 2 (S,Se) 3 /In 2 S 3 heterostructures.