SnS x /SrTiO3 Nanocomposites for Solar-to-Hydrogen Conversion

Abstract

Large-scale application of direct solar-to-hydrogen technology requires cost-effective and readily available base materials for photocatalysis. Perovskite materials are currently undergoing extensive research aimed at enabling widespread use at a low cost, making compounds like SrTiO3 promising candidates as base materials for large-scale photocatalysts. In this study, we focused on the hydrothermal synthesis of tin sulfide (SnSx) embedded on SrTiO3 to form nanocomposites with varying weight percentages (5%, 10%, 15%, and 20% wt) for photocatalytic hydrogen production. The nanocomposites were characterized using X-ray diffraction and scanning electron microscopy to confirm the formation of SnSx on SrTiO3. Photocatalytic hydrogen production experiments were conducted under 4 h of simulated solar illumination. The optimum hydrogen production was achieved with 10% wt SrTiO3/SnSx (273.1 μmol g−1 h−1) compared to 54.4 μmol g−1 h−1 for pure SrTiO3. In contrast, pure tin sulfide showed no photocatalytic activity due to the rapid recombination of photogenerated electrons and holes. Nevertheless, this study clearly demonstrates that tin sulfide can function as a co-catalyst material in the formation of SrTiO3/SnSx nanocomposites, enhancing hydrogen production by facilitating electron excitation, increasing the effective surface area of SrTiO3, and effective photogenerated charge separation. Overall, the results highlight the potential of low-cost, noble-metal-free nanocomposite photocatalysts as promising candidates for efficient solar-to-hydrogen conversion via water splitting, leveraging the chemical versatility of perovskite materials to fine-tune photocatalytic properties.