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Photocatalytic CO2 reduction (PCR) expresses great attraction to convert useless greenhouse gas into valuable chemical feedstock. However, the weak interactions between catalytic sites and PCR intermediates constrains the PCR activity and selectivity. Herein, we proposed a new strategy to match the intermediates due to the maximum orbital overlap of catalytic sites and C1 intermediates by establishing dual Jahn–Teller (J–T) sites, in which, the strongly asymmetric J–T sites can break the nonpolar CO2 molecules and self‐adapt the different structure of C1 intermediates. Taking cobalt carbonate hydroxide as an example, the weakly symmetric dual cobalt (Co2) dual J–T sites, weakly asymmetric Fe&Co sites and strongly asymmetric Cu&Co sites were assembled. After illumination, the interaction between dual J–T sites and the CO2 molecules enhances J–T distortion, which further modulates the PCR activity and selectivity. As a result, the Cu&Co sites exhibited CO yield of 8137.9 μmol g−1, about 2.3‐fold and 4.2‐fold higher than that of the Fe&Co and Co2 sites within 5‐hour photoreaction, respectively. In addition, the selectivity achieved as high as 92.62 % than Fe&Co (88.67 %) and Co2 sites (55.33 %). This work provides a novel design concept for the construction of dual J–T sites to regulate the catalytic activity and selectivity. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermally stable, acid‐resistant nickel catalysts are highly desired in hydrogenation reactions, but such a catalyst remains absent owing to the inherent vulnerability of nickel under acidic conditions. An ultra‐durable Ni‐N‐C single‐atom catalyst (SAC) has now been developed that possesses a remarkable Ni content (7.5 wt %) required for practical usage. This SAC shows not only high activities for hydrogenation of various unsaturated substrates but also unprecedented durability for the one‐pot conversion of cellulose under very harsh conditions (245 °C, 60 bar H2, presence of tungstic acid in hot water). Using integrated spectroscopy characterization and computational modeling, the active site structure is identified as (Ni‐N4)⋅⋅⋅N, where significantly distorted octahedral coordination and pyridinic N constitute a frustrated Lewis pair for the heterolytic dissociation of dihydrogen, and the robust covalent chemical bonding between Ni and N atoms accounts for its ultrastability. [ABSTRACT FROM AUTHOR]