Enhancing catalytic transfer semi-hydrogenation of alkynes over N-doped carbon-supported Pd–Ni bimetallic catalysts

Abstract

Olefin is a crucial chemical intermediate that is in high demand for polymer production. The catalytic alkyne semi-hydrogenation process represents a promising avenue for industrial purification of olefins. Herein, we report the findings of a study investigating the transfer of alkyne semi-hydrogenation over a bimetallic catalyst, in which Pd nanoparticles and highly dispersed Ni atoms were anchored onto graphite-like C₃N₄ with nitrogen defects. The optimal Pd_0.14Ni_0.01 catalyst was used for intermolecular semi-hydrogenation of alkynes in conjunction with sodium borohydride. Nitrogen defects heightened the catalytic activity by modifying the electron density distribution and accelerating charge transfer from Pd to C₃N₄. Furthermore, the synergism of the Pd–Ni bimetallic positions facilitated the generation of the intermediate styrene and accelerated the rate-determining step. This study provides novel insights into the design of streamlined high-performance semi-hydrogenated catalysts.