Two-dimensional metal sulfides such as SnS₂ play a pivotal role in the field of environmental energy due to their suitable optical bandgap and high specific surface area. However, the steady-state 2H-phase SnS₂ suffers from rapid charge recombination and low CO₂ catalytic activity, limiting its practical application in photocatalytic CO₂ reduction. In this work, we designed a CuPd/SnS₂ heterojunction system by loading CuPd nanoparticles onto SnS₂ nanosheets (NSs). Under illumination, the hot electrons excited in CuPd nanoparticles induce a 2H-1T-phase transition of SnS₂, effectively improving the photogenerated carrier dynamics of the material. Additionally, the post-transition energy level structure facilitates more efficient injection of photogenerated electrons into highly catalytic CuPd particles, achieving the goal of photocatalytic reduction of CO₂ to C₂H₆. Resultingly, the CuPd/SnS₂ photocatalytic system achieves a C₂H₆ production rate of 255.6 μmol g^–1 h^–1, which is approximately 24.4 times and 3.9 times higher than that of Cu/SnS₂ and Pd/SnS₂, respectively. Moreover, it boasts a remarkable product selectivity of up to 90.4% for C₂H₆. This study provides a valuable approach for modulating photogenerated carrier dynamics and enhancing catalytic activity in two-dimensional metal sulfides.

中文翻译：

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反向电子转移诱导的 SnS2 相变用于高效光催化 CO2–C2H6 转化


二维金属硫化物（如 SnS₂）由于其合适的光学带隙和高比表面积，在环境能源领域发挥着举足轻重的作用。然而，稳态 2H 相 SnS₂ 具有快速电荷复合和 CO₂ 催化活性低的特点，限制了其在光催化 CO₂ 还原中的实际应用。在这项工作中，我们通过将 CuPd 纳米颗粒加载到 SnS₂ 纳米片 （NSs） 上来设计了 CuPd/SnS₂ 异质结系统。在光照下，CuPd 纳米颗粒中激发的热电子诱导 SnS₂ 发生 2H-1T 相变，有效改善了材料的光生载流子动力学。此外，后跃迁能级结构有助于更有效地将光生电子注入高催化性 CuPd 颗粒中，实现将 CO₂ 光催化还原为 C₂H₆ 的目标。结果，CuPd/SnS₂ 光催化体系实现了 255.6 μmol g^–1 h^–1 的 C₂H₆ 生成速率，分别比 Cu/SnS₂ 和 Pd/SnS₂ 高约 24.4 倍和 3.9 倍。此外，它对 C₂H₆ 具有高达 90.4% 的出色产品选择性。本研究为调节光生载流子动力学和增强二维金属硫化物中的催化活性提供了一种有价值的方法。