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[Display omitted] Simultaneously enhancing the durability and catalytic performance of metal-nitrogen-carbon (M−N x −C) single–atom catalysts is critical to boost oxygen electrocatalysis for energy conversion and storage, yet it remains a grand challenge. Herein, through the combination of early and late metals, we proposed to enhance the stability and tune the catalytic activity of M−N x −C SACs in oxygen electrocatalysis by their strong interaction with the M 2 ′C–type MXene substrate. Our density functional theory (DFT) computations revealed that the strong interaction between "early-late" metal–metal bonds significantly improves thermal and electrochemical stability. Due to considerable charge transfer and shift of the d-band center, the electronic properties of these SACs can be extensively modified, thereby optimizing their adsorption strength with oxygenated intermediates and achieving eight promising bifunctional catalysts for ORR/OER with low overpotentials. More importantly, the constant-potential analysis demonstrated the excellent bifunctional activity of SACs supported on MXene substrate across a broad pH range, especially in strongly alkaline media with record-low overpotentials. Further machine learning analysis shows that the d-band center, the charge of the active site, and the work function of the formed heterojunctions are critical to revealing the ORR/OER activity origin. Our results underscore the vast potential of strong interactions between different metal species in enhancing the durability and catalytic performance of SACs. [ABSTRACT FROM AUTHOR]

By performing DFT computations, we proposed a promising strategy to tune the ORR/OER catalytic performance of transition metal-nitrogen-carbon by constructing heterostructure with graphdiyne. We found the d-band center and charge transfer of the TM active sites can correlate the ORR/OER catalytic activity and their electronic properties for TM N C/GDY. [Display omitted] • The catalytic activities of the heterostructure between TM N C with GDY (TM N C/GDY) for ORR/OER were studied by means of density functional theory. • Co N C/GDY can be proposed as a bifunctional catalyst for ORR/OER with low overpotential. • According to the constant-potential method, the acidic condition is conducive to boost bifunctional catalytic activity for Co N C/GDY. Exploring high-efficiency electrocatalysts to boost the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is pivotal to the large-scale applications for clean and renewable energy technologies, such as fuel cells, water splitting, and metal–air batteries. Herein, by means of density functional theory (DFT) computations, we proposed a strategy to modulate the catalytic activity of transition metal-nitrogen-carbon catalysts through their interface engineering with graphdiyne (TM N C/GDY). Our results revealed that these hybrid structures exhibit good stability and excellent electrical conductivity. Especially, Co N C/GDY was identified as a promising bifunctional catalyst for ORR/OER with rather low overpotentials in acidic conditions according to the constant-potential energy analysis. Moreover, the volcano plots were established to describe the activity trend of the ORR/OER on TM N C/GDY using the adsorption strength of the oxygenated intermediates. Remarkably, the d-band center and charge transfer of the TM active sites can be utilized to correlate the ORR/OER catalytic activity and their electronic properties. Our findings not only suggested an ideal bifunctional oxygen electrocatalyst, but also provided a useful strategy to obtain highly efficient catalysts by interface engineering of two-dimensional heterostructures. [ABSTRACT FROM AUTHOR]