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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]

[Display omitted] • M-N-C/MoS 2 heterostructures exhibit good structural stability, excellent electrical conductivity, and improved stiffness. • The anchored Ir-N-C, Rh-N-C, and Co-N-C are identified as eligible bifunctional ORR/OER electrocatalysts. • The optimal binding strength with the oxygenated intermediates endow anchored M-N-C good catalytic performance. The development of highly-efficient bifunctional oxygen electrocatalysts is essential to the large-scale commercialization of energy-related conversion and storage technologies. In this work, using first-principle computations, we systematically investigated the catalytic activities of a variety of metal-N-C/MoS 2 heterostructures (M-N-C/MoS 2 , M = Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ag, Os, Ir, and Pt) towards the oxygen reduction/evolution reactions (ORR/OER). Our result revealed that these M-N-C/MoS 2 heterostructures exhibit good structural stability, excellent electrical conductivity, and improved stiffness. Furthermore, the anchored Ir-N-C was identified as the best bifunctional ORR/OER electrocatalyst due to its lowest overpotentials (0.28/0.38 V) among all candidates, which were well rationalized by its optimal binding strength with the oxygenated intermediates. Thus, by combining M-N-C and MoS 2 monolayer, the highly-efficient bifunctional ORR/OER electrocatalysts can be achieved, which offers a new strategy to further explore heterostructures-based materials for other electrochemical processes. [ABSTRACT FROM AUTHOR]

Here, L1 (2‐(pyridin‐2‐yl)quinoxaline) and L2 ((1‐((1H‐pyrrol‐2‐yl)ethylidene)benzene‐1,2‐diamine) ⋅ (1‐(1H‐pyrrol‐2‐yl)ethanone)) were synthesized and reacted with CoCl2 ⋅ 6H2O and NiCl2 ⋅ 6H2O to produce complexes 1–4. We found several interesting pieces of crystal structure information. Firstly, ligands L1 and L2 with completely different molecular structures were obtained by reacting the precursors containing similar N‐heterocycles with 1,2‐diaminobenzene. Secondly, in methanol and DMF solvents, 1 showed two structures, the binuclear and mononuclear cobalt complexes 1 a and 1 b. Finally, the structure of 4 showed the formation of a new 2 : 1 type ligand at eutectic L2 in the presence of a Ni2+ template. Upon treatment with AIBN, 1–4 showed moderate to high activities for MMA polymerization, producing PMMA with low to high molecular weights (2.02∼73.03×104 g⋅mol‐1) and moderate dispersity indices (PDI: 1.72∼3.32). Moreover, 1 b displayed higher catalytic activities (up to 1.138×105 g mol−1 ⋅ h−1), which was 20 times higher than that of 3 and more than 7 times higher than that of 1 a. [ABSTRACT FROM AUTHOR]