PdPt Alloy Nanocatalysts Supported on TiO2: Maneuvering Metal-Hydrogen Interactions for Light-Driven and Water-Donating Selective Alkyne Semihydrogenation

Low power consumption and minimal potential hazards are ultimate goals for the modern development of chemical manufacturing; however, it often reduces the selectivity of chemical reactions by implementing a new reaction system. A nanocatalyst design is reported for achieving efficient and selective alkyne semihydrogenation through the photocatalytic hydrogen transfer from water, which avoids the use of a heat source and explosive H-2. The PdPt catalytic sites that are implemented on the TiO2 photocatalyst hold the key to achieving both high activity and selectivity. As compared with pure Pd or Pt, the alloy cocatalysts can better harness H diffusion/desorption for selective semihydrogenation as well as suppress competitive H-2 evolution. This work opens up new possibilities for green and selective alkyne semihydrogenation and highlights the importance of lattice engineering to catalytic selectivity.