Improving the Activity of Electrocatalysts toward the Hydrogen Evolution Reaction, the Oxygen Evolution Reaction, and the Oxygen Reduction Reaction via Modification of Metal and Ligand of Conductive Two-Dimensional Metal-Organic Frameworks.

Exploring efficient and stable electrocatalysts for the hydrogen evolution reaction (HER) and the oxygen evolution and reduction reactions (OER and ORR) is vital to the development of renewable energy technologies. Herein, on the basis of density functional theory (DFT) calculations, we systematically investigated 30 TMNxO4-x-HTP (TM = Fe, Co, Ni, Ru, Rh and Pd; x = 0-4; HTP refers to hexatriphenylene) analogs of conductive two-dimensional (2D) metal-organic frameworks (MOFs) as potential catalysts for HER, OER, and ORR. The results show the good stabilities and metallic features of TMNxO4-x-HTP. The interaction strength between intermediates and catalysts governs the catalytic activities, which can be modulated by tuning the TM atom and the local coordination number of N/O in catalysts. RhN3O1-HTP is an efficient bifunctional catalyst for HER and OER, and RhN1O3-HTP is a promising bifunctional catalyst for OER and ORR. Our findings highlight a potentially efficient class of electrocatalysts based on 2D MOF materials.