Bimetallic alloy of CuPd nanoclusters decorated SnNb₂O₆ nanosheets (CuPd/SN) as a multifunctional photocatalyst has been constructed successfully. Compared with SN, CuPd/SN achieves an excellent performance for semihydrogenation of phenylacetylene under visible light irradiation. Especially, CuPd/SN with the Cu:Pd molar ratio of 3:1 exhibits the highest catalytic conversion efficiency for phenylacetylene (99.6%) with high selectivity of phenylethylene (99.4%). In situ FTIR result reveals that SN could activate phenylacetylene via a C≡C→Nb π-bonded coordination which improves the selectivity of phenylethylene. Experiment results indicate that atom Pd in alloy is responsible for dissociation H₂, while Cu represses the overhydrogenation. Electrochemical measurements indicates that CuPd alloy on SN surface could greatly minimize the recombination of photogenerated electron−hole pairs. The separated electrons further facilitate the production of active H. Hydrogen spillover would transfer active H to Nb site for phenylacetylene semihydrogenation. Finally, a synergetic catalytic mechanism is deeply discussed at molecule scale. This work would provide a deep insight for designing a multifunctional photocatalyst.

CuPd纳米团簇的双金属合金装饰SnNb ₂ O ₆纳米片（CuPd/SN）作为多功能光催化剂已成功构建。与SN相比，CuPd/SN在可见光照射下实现了苯乙炔半氢化的优异性能。特别是，Cu:Pd摩尔比为3:1的CuPd/SN对苯乙炔的催化转化效率最高（99.6%），对苯乙炔的选择性高（99.4%）。原位 FTIR 结果表明，SN 可以通过 C≡C→Nb π 键配位活化苯乙炔，从而提高苯乙炔的选择性。实验结果表明，合金中的原子 Pd 负责解离 H ₂，而 Cu 抑制过度氢化。电化学测量表明，SN 表面上的 CuPd 合金可以大大减少光生电子 - 空穴对的复合。分离的电子进一步促进了活性 H 的产生。氢溢出会将活性 H 转移到 Nb 位点进行苯乙炔半氢化。最后，在分子尺度上深入讨论了协同催化机制。这项工作将为设计多功能光催化剂提供深刻的见解。