Molecular machine-inspired design of axial and bivalent dual-atom catalysts for enhanced oxygen evolution/reduction reactions within van der Waals gap

Abstract

Dual-atom catalysts (DACs) upon porphyrins (Por) and phthalocyanines (Pht) have been widely used for oxygen evolution and/or reduction reactions (OER and/or ORR). However, the van der Waals (vdW) interactions’ effect on their performances has not been systematically explored. In this study, the vdW interactions in double-layers of X-Co(III)PorCo(II)Pht-DACs were leveraged to enhance ORR and OER performances. Thus, these authors have used dispersion corrected density functional theory (DFT) with Becke-Johnson damping function (D3) to investigate double-layers of X-Co(III)PorCo(II)Pht-DACs, through which X represented F, Cl, Br, I, or OH, in order to discover DACs with low ORR and OER overpotentials. Current findings revealed that, the ORR and OER may happen inside the vdW gap of Br-Co(III)PorCo(II)Pht-DAC, leading to 0.16 and 0.17 V overpotentials, respectively. The enhanced ORR and OER activities were rationalized to be due to the charge distribution associated with the tuned vdW interactions. Moreover, Density of States (DOS) analysis indicated the hybridization of the d orbitals of Co atoms with the p orbitals of the *OH and/or *O intermediates during the ORR and OER. This study provided crucial insights into the development of next-generation catalysts, showcasing the effectiveness of vdW interactions in electrocatalysis at room temperature.