On the Role of Surface Modifications of Palladium Catalysts in the Selective Hydrogenation of Acetylene

Summing Me up: DFT calculations have shown that alloying, subsurface carbon, and hydride formation, all increase the selectivity of Pd catalysts for acetylene hydrogenation by weakening the surface–adsorbate bond. A simple descriptor—the adsorption energy of a methyl group—has been used to quantify and compare the different effects in the adsorption of acetylene and ethylene on various transition-metal surfaces (see picture).