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eNRR is a promisingly environment-friendly strategy to obtain ammonia under ambient conditions. For metal-based catalysts, the competitive adsorption of H+ over N2 remains the primary hurdle for high ammonia yield and faradaic efficiency. Carbon-based metal-free catalysts attract our attention for the potential of being promising NRR catalysts due to their natural low HER activity. In this study, we prepared a modified Zn-based metal–organic framework (Zn-BTC) decorated with Cl ions by simply adding NaCl in the synthetic process. The existence of Cl ions in the framework contributes to the generation of large pores during thermolysis. Moreover, –Cl and –COCl species were formed in situ and connected with carbon atoms in the defect area. Benefitting from such a structure, this catalyst achieves a high ammonia yield rate of 103.96 μg h−1 mgcat−1 and a faradaic efficiency of 21.71% at room temperature. Theoretical results also proved that the newly produced –COCl and –Cl functional groups could attract more electrons from adjacent carbon atoms due to their stronger electronegativity, thus improving its affinity towards N2 while lowering the HER activity as reactive sites. [ABSTRACT FROM AUTHOR]

Transition metal sulfides have attracted tremendous attention as promising lithium-ion anodes due to their natural abundance, intrinsic safety and high theoretical capacity. However, low conductivity and dramatic volume variation hinder their further application in lithium storage. Here, we reported a facile metal–organic framework (MOF)-derived self-template approach to prepare hollow cobalt sulfide polyhedra with vertically aligned metallic phase MoS2 nanosheets (denoted as CoS@1T-MoS2) as efficient anode materials for lithium storage. Benefiting from the high intrinsic conductivity of metallic phase MoS2, the hierarchical hollow framework, and the synergistic effect of interior cobalt sulfide and exterior metallic MoS2, the CoS@1T-MoS2 composite delivers a high reversible capacity of 1269 mA h g−1 after 100 cycles at a current density of 100 mA g−1 and 936 mA h g−1 at a current density of 1000 mA g−1 after 220 cycles. [ABSTRACT FROM AUTHOR]