Single‐atom sites can not only act as active centers, but also serve as promising catalyst regulators and/or promoters. However, in many complex reaction systems such as electrochemical CO2 reduction reaction (CO2RR), the introduction of single‐atom regulators may inevitably induce the competitive hydrogen evolution reaction (HER) and thus reduce the selectivity. Here, the authors demonstrate that introducing HER‐inert main‐group metal single atoms adjacent to transition‐metal single atoms can modify their electronic structure to enhance the CO2RR to CO without inducing the HER side reaction. Dual‐metal Cu and In single‐site atoms anchored on mesoporous nitrogen‐doped carbon (denoted as Cu‐In‐NC) are prepared by the pyrolysis of a multimetallic metal–organic framework. Cu‐In‐NC shows a high faradic efficiency of 96% toward CO formation at −0.7 V versus reversible hydrogen electrode, superior to that of its monometallic single‐atom counterparts. Density functional theory studies reveal that the HER‐inert In sites can activate the adjacent Cu sites through electronic modifications, strengthening the binding of *COOH intermediate and thus boosting the electrochemical reduction of CO2 to CO.

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Tuning the electronic structure of the active center is effective to improve the intrinsic activity of single‐atom catalysts but the realization of precise regulation remains challenging. Herein, a strategy of “synergistically near‐ and long‐range regulation” is reported to effectively modulate the electronic structure of single‐atom sites. ZnN4 sites decorated with axial sulfur ligand in the first coordination and surrounded phosphorus atoms in the carbon matrix are successfully constructed in the hollow carbon supports (ZnN4S1/P‐HC). ZnN4S1/P‐HC exhibits excellent performance for CO2 reduction reaction (CO2RR) with a Faraday efficiency of CO close to 100%. The coupling of the CO2RR with thermodynamically favorable hydrazine oxidation reaction to replace oxygen evolution reaction in a two‐electrode electrolyzer can greatly lower the cell voltage by 0.92 V at a current density of 5 mA cm−2, theoretically saving 46% of energy consumption. Theoretical calculation reveals that the near‐range regulation with axial thiophene‐S ligand and long‐range regulation with neighboring P atoms can synergistically lead to the increase of electron localization around the Zn sites, which strengthens the adsorption of *COOH intermediate and therefore boosts the CO2RR.

In this paper, zeolitic imidazolate framework‐8 modified by the ethanediamine (NH2‐ZIF‐8) was employed for adsorbing Au (III) and Ag(I) from aqueous solutions. The adsorption capacities of NH2‐ZIF‐8 towards Au (III) and Ag(I) were found to be significantly affected by the pH values of the solution. The adsorption kinetics studies show that NH2‐ZIF‐8 presents a fast adsorption property towards metals, attaining 93% of adsorption equilibrium uptake for Au (III) within the first 30 min. This phenomenon can be ascribed to the coordination interaction between the amino group and Au (III). The thermodynamic data suggest that the adsorption of NH2‐ZIF‐8 towards Au (III) is endothermic process, while that for Ag(I) is exothermic. The maximum adsorption capacities of NH2‐ZIF‐8 toward Au (III) and Ag(I) can be achieved to 357 mg·g−1 and 222.25 mg·g−1, respectively. The metal ions interference results show that Cu (II) and Ni (II) hardly have no interference on Au (III) adsorption in e‐waste containing 1500 mg·l−1 Cu (II),100 mg·l−1 Ni (II) and 10 mg·l−1 Au (III); while for Ag(I), Cd (II) and Zn (II) have little interference on Ag(I) adsorption in the hybrid solutions containing Ag(I), Ni (II), Cd (II) and Zn (II) with equal concentration (50 mg·l−1), but Ni (II) interference most. The XPS study shows that partial Au (III) was reduced to Au(I), and that Ag(I) was completely reduced to Ag(0) during the adsorption process. The abundant of active sites of NH2‐ZIF‐8 containing C=N, N‐H, and Zn‐OH groups play a key role in the adsorption of Au (III) and Ag(I). In addition, electrostatic interaction can be responsible for the adsorption of Au (III) by NH2‐ZIF‐8. The regeneration experiments results show that the adsorption capacities of NH2‐ZIF‐8 towards Au (III) and Ag(I) can maintain after three cycles. This work provides a reliable method to improve the adsorption kinetics for metal ions.

An efficient and convenient method is developed for the direct esterification of P(O)-OH compounds with alcohols under room temperature. The protocol makes use of inexpensive uroniumbased salts as coupling reagents and shows good tolerance towards numerous alcohols, giving the corresponding esterification products in good to excellent yield. Phenols are also tolerated in this reaction. It is a simple way to produce a broad spectrum of functionalized phosphinates, phosphonates, and phosphates from basic P(O)-OH starting materials.

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Nitrogen-rich zeolitic imidazolate frameworks (ZIFs) are ideal precursors for the synthesis of metal single atom anchored on N-doped carbon. However, the microporous structures of conventional ZIFs lead to low mass...