Construction of Asymmetrical Dual Jahn-Teller Sites for Photocatalytic CO2 Reduction

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 C-1 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 C-1 intermediates. Taking cobalt carbonate hydroxide as an example, the weakly symmetric dual cobalt (Co-2) 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 & mu;mol g(-1), about 2.3-fold and 4.2-fold higher than that of the Fe & Co and Co-2 sites within 5-hour photoreaction, respectively. In addition, the selectivity achieved as high as 92.62 % than Fe & Co (88.67 %) and Co-2 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.