Enhancing Photocatalytic Performance by One-Step Vapor Deposition of SnSe/SnSe2 Composites

Two-dimensional materials and their van der Waals heterostructures offer significant advantages in photoelectrochemical (PEC) photodetectors and water splitting due to their unique physical and chemical properties. In this study, SnSe, SnSe₂, and SnSe/SnSe₂ composites were successfully synthesized on FTO glass and carbon cloth substrates using a one-step vapor deposition method. Experimental results demonstrate that the SnSe/SnSe₂ composite exhibits a high photocurrent density (29.83 μA/cm²) and superior stability compared to individual SnSe and SnSe₂. Moreover, benefiting from its efficient light absorption and synergistic charge transfer, the SnSe/SnSe₂ composite shows excellent photocatalytic performance, achieving a total hydrogen production of 57.4 μmol/cm² within 2 h─7.5 times and 5.1 times higher than that of SnSe and SnSe₂, respectively. These findings highlight the significant advantages of composite materials in photocatalysis and water splitting applications. Furthermore, this work presents a simple one-step strategy for the preparation of SnSe/SnSe₂ on various substrates, providing a solid foundation for future research and practical applications in this field.