methods to suppress the release of CO 2 , using photo-or electrocatalysis. [7-10] Particularly, the electrocatalytic reduction can be a promising method for managing the global carbon balance and issues regarding energy generation, as it can convert CO 2 to C1 or C2 chemical products as fuel. [11,12] However, this reduction process faces significant challenges due to the chemical inertness of CO 2 , as there are high thermodynamic and kinetic barriers to obtain a successful electrocatalytic reduction of CO 2. Additionally, the CO 2-to-CO pathway is usually selected, because CO is the raw material of the Fisher-Tropsch process and other added-value hydrocarbons with wide distribution (C1-C3 products). [13-17] On the other hand, the competing hydrogen evolution reaction (HER) and the stable CO bond of CO 2 can optimize the catalytic system through the activity and selectivity during the CO 2-to-CO electrocatalytic process. [18-21] Metal-and nitrogen-coordinated materials dispersed on carbon matrix (M-N x-C), with a high density of active sites, have attracted increased interests in the field of electrocatalytic reduction of CO 2 , due to their low cost and high abundance of raw material. [22-28] Nitrogen coordinated metal as catalytic sites that could be designable to fit the especial functionality. As is already known, the Cu-N x-C sites can have much more interaction with the oxygen of the CO 2 , which can enhance the enthalpy of the CO 2 and inhibit the HER but results in sluggish kinetics of the CO 2 + H + + e − → COOH* process. [29,30] Besides, the Fe-N x-C materials are often applied in CO 2 reduction with low onset potential. Nevertheless, the desorption of *CO into the gas phase can reduce the reactivity, due to the strong binding of CO to the Fe-N x-C sites in the step of COOH* + H + + e − → CO* + H 2 O and CO* → CO+ *. [31-33] Considering the issues mentioned above, to maximize the potential of single-atom catalysts for multistep catalytic reaction, we design and synthesize biatomic active sites of Cu-Fe-N 6-C catalyst by pyrolysis of PcCu-Fe-ZIF-8 under an argon atmosphere at 1000 °C (the detail can be found in the Supporting Information). The configuration and coordination environment of the diatomic catalyst are evidenced by the aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (STEM) (AC HAADF-STEM) and X-ray adsorption spectroscopy. The experimental results show To relieve the green gas emission and involve the carbon neutral cycle, electrochemical reduction of CO 2 attracts more and more attention. Herein, a biatomic site catalyst of Cu-Fe coordinated with the nitrogen, which is doped in the carbon matrix (denoted as Cu-Fe-N 6-C), is designed. The as-obtained Cu-Fe-N 6-C exhibits higher performance than that of Cu-N-C and Fe-N-C, owing to bimetallic sites, proving synergistic functions based on different molecules and their interfaces. Cu-Fe-N 6-C shows high selectivity toward CO, with high Faradaic efficiency (98% at −0.7 V), and maintaining 98% of its in...

In the area of catalysis, selective reduction of nitro compounds to amino compounds is a colossal challenge due to the existence of competitive reducible functional groups. Herein, an Fe-based catalyst FeSAs/Fe2O3ACs/N-doped polyhedral carbon (NPC) has been designed and synthesized. As we expected, compared with FeSAs and FeNPs, FeSAs/Fe2O3ACs/NPC shows excellent catalytic performance (turnover frequency up to 1923 h–1, calculated with nitrobenzene), chemoselectivity, and tolerance during the hydrogenation reaction of nitro compounds under room temperature because of the synergistic effects between FeSAs and Fe2O3ACs. The theoretical calculations show that FeSAs prefers to undergo hydrazine decomposition to generate hydrogen and the Fe2O3ACs surface is more active toward the nitrobenzene reduction to aniline.

HNUST-8 exhibits water stable, efficient CH4/CO2 storage and separation, acid–base cooperative catalytic activity in a tandem deacetalization Knoevenagel densation.

An expanded 4,4-paddlewheel-connected porous MOF-505-type metal-organic framework (MOF), [Cu2(PDEB)(H2O)2]·xS (NJU-Bai12; NJU-Bai represents the Nanjing University Bai group and S represents noncoordinated solvent molecules) has been designed from a nanosized rectangular diisophthalate linker containing alkyne groups 5,5'-(1,4-phenylenedi-2,1-ethynediyl)bis(1,3-benzenecarboxylic acid). This MOF material possesses permanent microporosity with the highest Brunauer-Emmett-Teller surface area of 3038 m(2)·g(-1) and the largest unsaturated total hydrogen storage capacity of 62.7 mg·g(-1) at 77 K and 20 bar among reported MOF-505 analogues. Additionally, NJU-Bai12 also exhibits excellent carbon dioxide (CO2) uptake capacity (23.83 and 19.85 mmol·g(-1) at 20 bar for 273 and 298 K, respectively) and selective gas adsorption properties with CO2/CH4 selectivity of 5.0 and CO2/N2 selectivity of 24.6 at room temperature.

Herein, we designed and prepared a novel Fe/Fe2O3‐based catalyst, in which a remarkable synergistic effect has been revealed between Fe and Fe2O3 encapsulated in N‐doping porous carbon. The Fe‐based catalysts were fabricated via pyrolysis a mixture of MIL‐101(Fe) and melamine. The catalyst exhibits exceptionally high catalytic activity (TOFs up to 8898 h−1 which is about 100 times higher than the similar kinds of catalysts) and chemoselectivity for nitroarene reduction under mild conditions.

Synergistic effects of multimetallic catalysts play a crucial role in the field of heterogeneous catalysis, especially in the oxidation and reduction of functional groups. Hence, how to design a multimetallic catalyst with high catalysis performance attracts the attention of scientists. Herein, we have designed and synthesized a cobalt−nickel bimetallic catalyst step by step. More interestingly, the cobalt−nickel nanoparticles were encapsulated in N-doped hollow porous carbon (HPC), on which were grown many carbon tubes. The optimized nanoparticle as a hydrogenation catalyst exhibits superior performance in the selective reduction of quinoline at ambient temperature, due to its advantage of dispersing uniform bimetal nanoparticles and Ndoped active sites.

A microporous oxalamide-functionalized NbO-type metal− organic framework, HNUST-3, has been designed and synthesized by selfassembling [Cu 2 (COO) 4 ] paddlewheel SBUs and a novel tetracarboxylate ligand with linking oxalamide groups. HNUST-3 represents the first example of a porous oxalamide-functionalized MOF, which exhibits a high BET surface area of 2412 m 2 •g −1 , large H 2 uptake (unsaturated total capacity of 6.1 wt % at 20 bar and 77 K), and excellent CH 4 storage (135.8 cm 3 (STP)cm −3 at 20 bar and 298 K) as well as high CO 2 adsorption capacity (20.2 mmol•g −1 at 20 bar and 298 K) with good selectivity for CO 2 over CH 4 (7.9) and N 2 (26.1) at 298 K.

Herein, a series of Fe-based catalysts have been designed and prepared by grinding a mixture of MIL-88d and melamine, and then the mixture was followed by pyrolysis. An unusual Fe/Fe3C-activated site is uniformly encapsulated in the N-doped carbon tubes obtained by pyrolysis of the film-like nanocrystals of MIL-88d. Experimental characterizations and theoretical calculations demonstrate that the surface N sites can effectively trap the nitrobenzene and aniline by their phenyl groups with the formation of three C–N bonds that made the catalyst exhibit excellent catalytic activity (turnover frequencies of ≤11268 h–1 calculated on the basis of nitrobenzene) and chemoselectivity for the reduction of nitro derivatives under facile conditions.