Theoretical study of Co/C-doped MoP on electrocatalytic hydrogen precipitation performance under acidic media

Hydrogen prepared by electrolysis of water had received much attention due to its non-polluting and renewable characteristics. This method was limited by high energy barrier and high cost. So, it is necessary to develop catalysts that can replace Pt-based catalysts. In the present study, three doping positions on the catalyst surface are represented as X1, X2 and X1X2 (X = Co/C), respectively. The hydrogen evolution reaction (HER) on the crystal surface of initial model and heteroatom(Co/C) doped MoP (111) was explored by the density functional theory (DFT). The mechanism of improving the catalytic performance caused by doping was discussed through calculating its density of states, D-band center, population and other related properties. The synergy with the d orbital of Mo was enhanced which caused by an appropriate amount of Co/C doping that can change the surrounding electron exchange environment. After Co doping, its Delta GH* increased from -0.287 eV to -0.116 eV and 0.143 eV, respectively. While C doping also increased to -0.158 eV and -0.181 eV, respectively, which significantly enhanced the activity of the HER. Many experiments on the preparation of hydrogen take some method so far, i.e., doping transition metals, but few works comprehensively report on the mechanism of doping metals improving the performance of HER within the framework of density functional theory (DFT). The present work not only explains the improving performance of HER from the perspective of electron transfer within the DFT framework, but also sheds a light for subsequent experiments.

Automated summary

This study investigates the effect of doping on the hydrogen evolution reaction (HER) on MoP (111) using density functional theory (DFT), finding that an appropriate amount of Co/C doping significantly enhances the activity of HER.