Nitrogen‐doped graphdiynes recently emerged as promising metal‐free oxygen reduction reaction (ORR) electrocatalysts. However, which type of N‐dopants contributing to the enhanced catalytic performance and the catalytic performances of other heteroatom‐doped graphdiynes has not been explored systematically. Herein, ORR and oxygen evolution reaction (OER) catalytic performances of X‐doped graphdiynes are examined by means of DFT computations (X = B, N, P, and S). It is revealed that the graphitic S‐doped graphdiyne (Model S1), the sp‐N‐doped graphdiyne (Model N3) and the graphitic P‐doped graphdiyne (Model P1) exhibit comparable or even better ORR/OER activities than Pt/C or RuO2, with ORR activity trend as Model S1 > Pt/C > Model N3 and OER trend as Model P1 > RuO2 > Model N3. The carbon atoms near N‐ and S‐dopants and featuring large positive charge are the ORR active sites in Models N3 and S1, whereas the carbon atoms near N‐ and P‐dopants and possessing high spin are the OER active sites in Models N3 and P1. Overall, this study not only gains deep insights into the catalytic activity of N‐doped graphdiyne for ORR, but also guides developing of graphdiyne‐based ORR/OER catalysts beyond N‐doping.

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We perform first‐principles calculations to investigate whether or not nitrogen is the best dopant in system of Co−X4 embedded graphene (X=N, S, B, and P) electrocatalysts towards hydrogen evolution reaction(HER). Our theoretical results reveal that N, S, B, and P‐doped graphene can enhance the catalytic activity toward HER compared with the pristine graphene, and S doped graphene exhibits more favorable performance than N doped graphene, consistent with the experimental results. For the Co−X4 embedded graphene (X=N, S, B, and P), we predict that S may be a promising dopant in graphene supported single atom Co. The rather low hydrogen adsorption free energy (−0.07 eV) and activation energy barrier (0.78 eV) for the rate‐determining step, the downshift of the d band center, the enhanced charge density of dz2 orbital as well as the reduced work function are responsible for the unexpected activity of Co‐S4 embedded graphene for HER. Overall, Co‐S4 embedded graphene catalyst could be a good candidate for hydrogen evolution reaction.

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