Theoretical investigation of the hydrogen production by adsorption of methanol on bimetallic Pd-Ge (1 1 0) surface as future green combustible using DFT-D method: Energetic and structural aspect of interaction pathways of metal with methanol

Abstract

Dehydrogenation and adsorption mechanism of methanol on PdGe (110) surface was undertaken using self-consistent periodic DFT-D. Different kinds of adsorption modes of relevant intermediates on the surface were identified. It was found that methanol and CHO prefer to adsorb on top site(tPd), CH3O, CH2OH adsorb on top(tGe), while CHOH, COH, CO, and H adsorb on bridge(bPdPd) and CH2O on top(tPd; tGe) sites. The four-way reactions indicated that the initial OH bond scission of methanol seems to be more favorable than CH bond cleavage on PdGe (110) from the perspective of activation barriers. It is also shown that (CH3OH → CH3O → CH2O → CHO → CO) is the predominant pathway on PdGe (110). Ge Insertion in Pd(110) shows that the predominant path is different from those of Pd(100), Pd(111), also the activation barrier of PdGe (110) is lower than those of Pd(100), Pd(111).