Theoretical computation of the electrocatalytic performance of CO_2 reduction and hydrogen evolution reactions on graphdiyne monolayer supported precise number of copper atoms

摘要

CO2 reduction (CO2RR) and hydrogen evolution reactions (HER) are widely used in advanced energy conversion systems, which are urgently required low-cost and high efficient electrocatalysts to overcome the sluggish reaction kinetic and ultralow selectivity. Here, the single-, double-, and triple-atomic Cu embedded graphdiyne (Cu1-3@GDY) complexes have been systematically modeled by first-principles computations to evaluate the corresponding electric structures and catalytic performance. The results revealed that these Cu-1-(3)@GDY monolayers possess high thermal stability by forming the firm Cu-C bonds. The Cu-1-(3)@GDY complexes exhibit good electrical conductivity, which could promote the charge transfer in the electroreduction process. The electronic and magnetic interactions between key species (*H, *COOH, and *OCHO) and Cu1-3@GDY complexes are responsible for the different catalytic performance of HER and CO2RR on different Cu-1-(3)@GDY sheets. The Cu-2@GDY complex could efficiently convert CO2 to CH4 with a rather low limiting potential of -0.42 V due to the spin magnetism of catalysts. The Cu-1@CDY and CuAGDY exhibit excellent HER catalytic performance, and their limiting potentials are -0.18 and -0.02 V, respectively. Our findings not only provide a valuable avenue for the design of atomic metal catalysts toward various catalytic reactions but also highlight an important role of spin magnetism in electrocatalysts. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.