Developing highly efficient electrocatalysts based on cheap and earth-abundant metals for CO 2 reduction is of great importance. Here we demonstrate that the electrocatalytic activity of manganese-based heterogeneous catalyst can be significantly improved through halogen and nitrogen dual-coordination to modulate the electronic structure of manganese atom. Such an electrocatalyst for CO 2 reduction exhibits a maximum CO faradaic efficiency of 97% and high current density of ~10 mA cm −2 at a low overpotential of 0.49 V. Moreover, the turnover frequency can reach 38347 h −1 at overpotential of 0.49 V, which is the highest among the reported heterogeneous electrocatalysts for CO 2 reduction. In situ X-ray absorption experiment and density-functional theory calculation reveal the modified electronic structure of the active manganese site, on which the free energy barrier for intermediate formation is greatly reduced, thus resulting in a great improvement of CO 2 reduction performance.

Metal-organic frameworks (MOFs) have proven to be an interesting class of sacrificial precursors of functional inorganic materials for catalysis, energy storage, and conversion applications. However, the controlled synthesis of MOF-derived materials with desirable compositions, structures, and properties still remains a big challenge. Herein, we propose a post-solvothermal route for the outer-to-inner loss of organic linkers from MOF, which is simple, rapid, and controllable and can be operated at temperature much lower than that of the commonly adopted pyrolysis method. By such a strategy, the MIL-125-NH particles coated by TiO nanosheets were produced, and the thickness of TiO shell can be easily tuned. The MIL-125-NH@TiO core-shell particles combine the advantages of highly active TiO nanosheets, MIL-125-NH photosensitizer, plenty of linker defects and oxygen vacancies, and mesoporous structure, which allows them to be utilized as photocatalysts for the visible-light-driven hydrogen production reaction. It is remarkable that the hydrogen evolution rate by MIL-125-NH@TiO can be enhanced 70 times compared with the pristine MIL-125-NH. Such a route can be easily applied to the synthesis of different kinds of MOF-derived functional materials.

To develop photocatalysts with desirable compositions and structures for improving the efficiency and selectivity of CO conversion to CH under mild conditions is of great importance. Here, we design an effective photocatalyst of bimetal (Ag/Pd) nanoalloys supported on nitrogen-doped TiO nanosheet for CO conversion. Such a novel photocatalyst combines multiple advantages of abundant Ti ions, oxygen vacancies, and substitutional nitrogen that are favorable for catalyzing CO reduction. It was found that CO could be efficiently transformed to CH under mild conditions, i.e., in aqueous solution and at atmospheric pressure and room temperature. The maximum production rate of CH can reach 79.0 μmol g h. Moreover, the Ag/Pd bimetals supported on N-doped TiO nanosheet exhibit high selectivity to CH. The as-synthesized photocatalyst can be well recycled for CO reduction.

Herein, we demonstrate for the first time the one-step synthesis of ultrathin α-Co(OH)2 nanomeshes by an imidazole-directed route. The α-Co(OH)2 nanomeshes combine the advantages of ultrathin thickness (3 nm), small mesopores (3.7 nm), large specific surface area (181.1 m2 g-1) and high surface oxygen vacancy density, which exhibit excellent electrocatalytic performance for the oxygen evolution reaction.

Metal–organic frameworks (MOFs) have attracted increased research attention in photocatalysis due to their great potential in light harvest and conversion. However, the organic transformations as photocatalyzed by MOFs under mild conditions yet remain a challenge. Herein, three bipyridyl-containing cadmium–organic frameworks Cd­(dcbpy) (dcbpy = 2,2′-bipyridine-5,5′-dicarboxylate), Cd­(bdc)­(bpy) (bdc = 1,4-benzenedicarboxylate; bpy = 2,2′-bipyridyl), and Cd­(bdc)­(2Me-bpy) (2Me-bpy = 4,4′-dimethyl-2,2′-bipyridyl) were synthesized for the first time. The bpy-containing Cd-MOFs have strong light harvest abilities and suitable photocatalysis energy potentials, making them highly active and selective for the photo-oxidation of benzylamine to N-benzylbenzaldimine under mild conditions, i.e., using atmospheric air as oxidant, at room temperature, and in the absence of any photosensitizer or cocatalyst. It provides an efficient, economical, and green way for the direct oxidation of amines to produce imines.

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CuxNiy alloy nanoparticles embedded in a nitrogen–carbon network can effectively convert CO2 into CO under mild conditions.

The development of facile, rapid, low-energy, environmentally benign routes for the synthesis of covalent organic frameworks (COFs) is of great interest. This study concerns the utilization of water containing dissolved CO as a solvent for the room-temperature synthesis of COF. The as-synthesized particles, denoted COF-LZU1, combine advantages of good crystallinity, nanoscale size, and high surface area, which suggests promising application as a support for heterogeneous catalysts. Moreover, this versatile CO -assisted method is also applicable for the room-temperature synthesis of Cu-COF-LZU1. This method gives rise to new opportunities for fabricating COFs and COF-based materials with different compositions and structures.