Two-dimensional conductive π-conjugated metal-organic frameworks as promising electrocatalysts for highly efficient hydrogen evolution reaction

Abstract

Two-dimensional conductive π-conjugated metal-organic frameworks (2D c-MOFs), as a new promising electrocatalytic materials, have spurred great research interests, but the systematic research on the structure-property relationship of c-MOF-based electrocatalysts is scarcely reported. Herein we conduct a first-principles study on the screening of a family of 2D c-MOFs (TM3(HITN)2) as HER electrocatalysts, which are constructed by TM atoms and 2,3,8,9,14,15-hexaiminotrinaphthylene (HITN) functional groups. The data suggests that all these 2D TM3(HITN)2 possess metallic with good conductivity for electrochemical reactions due to their intrinsic π-electron conjugation and sufficient interaction between the TM atoms and the organic linkers. Through the complete computational screening, the Zr3(HITN)2 stands out because of its near-zero ΔG*H value and low activation energy barrier. Moreover, the distinguished HER performance of Zr3(HITN)2 can be attributed to the extremely enhanced electron density derived from the C-2p orbitals near the Fermi level accompanied by the size increase of the tri-dentated aromatic linkers. Hence, this study not only highlights a family of promising 2D c-MOF electrocatalysts toward HER, but also supplies a valuable insight on the design of novel and high-performance c-MOF-based materials for better electrocatalysis.