Design of Efficient Oxygen Reduction Reaction Catalysts with Single Transition Metal Atom on N-Doped Graphdiyne.

The revelation of the underlying structure-property relationship of single-atom catalysts (SACs) is a fundamental issue in the oxygen reduction reaction (ORR). Here we present systematic theoretical and experimental investigations of various N-doped graphdiyne (NGDY) supported transition metals (TMs) to shed light on this relationship. Calculation results indicate that the TMs' comprehensive activities follow the order of Pd@NGDY > Ni@NGDY > Co@NGDY > Fe@NGDY, which fits well with our experimental conclusion. Moreover, detailed structure-property relationship (194 in total) analysis suggests that the key-species binding stability (Δ G *OH ), the d-orbital center (ε d /ε d-a ) and charge transfer (ΔQ TM /ΔQ TM-a ) of the active metal before/after reactants adsorption and the bond length of TM-O (L TM-O ) as descriptors can well reflect the intermediate binding stability or ORR activity on different TM-SACs. Specifically, the change trend of catalytic activity is opposite to that of intermediate binding stability, meaning that too strongly bonded *OOH, *O, and *OH intermediates are unfavorable for ORR.