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Cobalt coordinated covalent organic frameworks have attracted increasing interest in the field of CO2 photoreduction to CO, owing to their high electron affinity and predesigned structures. However, achieving high conversion efficiency is challenging since most Co related coordination environments facilitate fast recombination of photogenerated electron-hole pairs. Here, we design two kinds of Co-COF catalysts with oxygen coordinated Co atoms and find that after tuning of coordination environment, the reported Co framework catalyst with Co-O4 sites exhibits a high CO production rate of 18000 µmol g−1 h−1 with selectivity as high as 95.7% under visible light irradiation. From in/ex-situ spectral characterizations and theoretical calculations, it is revealed that the predesigned Co-O4 sites significantly facilitate the carrier migration in framework matrixes and inhibit the recombination of photogenerated electron-hole pairs in the photocatalytic process. This work opens a way for the design of high-performance catalysts for CO2 photoreduction. A class of inexpensive aminoanthraquinone organic dyes are shown to facilitate visible-light-driven CO2 reduction. Overall reaction efficiencies were found to be optimal when both electron donating and accepting groups were on a single dye molecule. [ABSTRACT FROM AUTHOR]

Designing highly active and durable electrocatalysts remain an ongoing challenge in the oxygen reduction reaction (ORR). Here, the reductive IL/Ti3C2Tx(FA) is produced in a water‐free mixture of formic acid (FA), ionic liquid (IL) and LiF, subsequently, the simultaneous reduction encapsulation trap the Pd nanocatalysts and IL within bilayer carbide‐derived carbon (CDC) to obtain Pd@IL/CDC(FA) with high metal loading up to 69.7%. Thereby, the featured active phases in Pd@IL/CDC(FA) impart potent chemical nanoconfinement to defend metals from dissolution and aggregation, boost mass and electron transfer, and mediate oxidation states and adsorption/desorption of metal Pd in the ORR. Instead of deactivation and Ostwald ripening, the catalytic performances of Pd@IL/CDC(FA) are gradually enhanced in an accelerated durability test up to 20 000 cycles. In a Zn–air battery, the Pd@IL/CDC(FA) cathode gives a specific capacity of 812.6 mAh gZn−1 and a voltage loss of only 41 mV in galvanostatic discharge for 1000 h. The work opens new venues in controllably preparing high activity and durable electrocatalysts from in‐situ generated CDCs. [ABSTRACT FROM AUTHOR]