DFT Study of the BH4− Hydrolysis on Au(111) Surface

Abstract

The mechanism of the catalytic hydrolysis of BH4− on Au(111) as studied by DFT is reported. The results are compared to the analogous process on Ag(111) that was recently reported. It is found that the borohydride species are adsorbed stronger on the Au0-NP surface than on the Ag0-NP surface. The electron affinity of the Au is larger than that of Ag. The results indicate that only two steps of hydrolysis are happening on the Au(111) surface and the reaction mechanism differs significantly from that on the Ag(111) surface. These remarkable results were experimentally verified. Upon hydrolysis, only three hydrogens of BH4− are transferred to the Au surface, not all four, and H2 generation is enhanced in the presence of surface H atoms. Thus, it is proposed that the BH4− hydrolysis and reduction mechanisms catalyzed by M0-NPs depend considerably on the nature of the metal.