Facet-dependent electrooxidation of propylene into propylene oxide over Ag3PO4 crystals

Abstract The electrooxidation of propylene into propylene oxide under ambient conditions represents an attractive approach toward propylene oxide. However, this process suffers from a low yield rate over reported electrocatalysts. In this work, we develop an efficient electrocatalyst of Ag 3 PO 4 for the electrooxidation of propylene into propylene oxide. The Ag 3 PO 4 cubes with (100) facets exhibit the highest yield rate of 5.3 g PO m −2 h −1 at 2.4 V versus reversible hydrogen electrode, which is 1.6 and 2.5 times higher than those over Ag 3 PO 4 rhombic dodecahedra with (110) facets and tetrahedra with (111) facets, respectively. The theoretical calculations reveal that the largest polarization of propylene on Ag 3 PO 4 (100) facets is beneficial to break the symmetric π bonding and facilitate the formation of C-O bond. Meanwhile, Ag 3 PO 4 (100) facets exhibit the lowest adsorption energies of * C 3 H 6 and * OH, inducing the lowest energy barrier of the rate-determining step and thus accounting for the highest catalytic performance.