The Cd_xIn_yS_(x+1.5y) catalysts with gradient Cd:In ratios were controllably synthesized via an one-step hydrothermal approach. Particularly, the hydrothermal synthesis conferred those Cd_xIn_yS_(x+1.5y) catalysts with Cd:In ratios over 1:2 with a one-dimensional–three-dimensional heterojunction structure composed of CdS nanorods and cubic-phase CdIn₂S₄. Our characterization evidences reflected that the CdS nanorods effectively promoted the separation of photoexcited electron–hole pairs in Cd_xIn_yS_(x+1.5y) and enabled transboundary transfer of photogenerated carriers. Spectroscopic and experimental results were further employed to develop a detailed catalytic mechanism, in which the superoxide anion (•O₂⁻) plays an important role in the catalytic oxidation of HMF to DFF by Cd_xIn_yS_(x+1.5y). Unlike other photocatalysts with •O₂⁻ as the main active species, Cd_1.5In₂S_4.5 gives an excellent performance in HMF conversion. This shows the great potential of cadmium–indium sulfides as photocatalysts for biomass conversion under ambient conditions.

具有梯度 Cd:In 比率的 Cd _x In _y S _{( x +1.5 y )}催化剂是通过一步水热法可控合成的。特别地，水热合成赋予那些 Cd :In 比超过 1:2 的Cd _x In _y S _{( x +1.5 y )}催化剂具有由 CdS 纳米棒和立方相 CdIn ₂ S组成的一维-三维异质结结构₄ . 我们的表征证据表明，CdS 纳米棒有效地促进了 Cd _x In _y中光激发电子-空穴对的分离S _{( x +1.5 y )}和启用光生载流子的跨界转移。进一步利用光谱和实验结果开发了详细的催化机制，其中超氧阴离子 (•O ₂ ^- ) 在 Cd _x In _y S _{( x +1.5 y )}将 HMF 催化氧化为 DFF 中起重要作用。与其他以•O ₂ ⁻为主要活性物质的光催化剂不同，Cd _1.5 In ₂ S _4.5在 HMF 转换方面表现出色。这表明镉-铟硫化物在环境条件下作为生物质转化光催化剂的巨大潜力。