Selective hydrogenation of phenylacetylene over TiO₂ supported Ni₂P nanoparticles under visible light irradiation

The design of efficient photocatalysts for selective hydrogenation of phenylacetylene to styrene is challenging. Herein, TiO2 supported Ni2P nanoparticles (Ni2P/TiO2) were prepared by a simple low temperature in situ phosphating method. As an earth-abundant and low-cost material, the optimal catalyst exhibits excellent photocatalytic activity with 99.9% phenylacetylene conversion and 96.0% styrene selectivity at 80 degrees C under visible light irradiation. The adsorption of phenylacetylene was weakened due to the isolation effect and electronic effect of P, which inhibited the over-hydrogenation of styrene and assured its high selectivity. The introduction of P also promoted the light absorption of the catalyst and accelerated the activation of H-2 to provide active H species, which improved photocatalytic performance. Besides, the introduction of P overcomes the disadvantages of easy oxidation of metallic nickel-based catalysts, which ensure the excellent stability and recyclability of the Ni2P/TiO2 photocatalyst.