Metal-organic layers as a platform for developing single-atom catalysts for photochemical CO2 reduction
AUTHORS: Zhang, JH; Yang, W; Zhang, M; Wang, HJ; Si, R; Zhong, DC; Lu, TB
The photochemical reduction of carbon dioxide (CO2) into valuable chemicals or feedstock is very meaningful for environmental and energy sustainability. Development of efficient, robust and low-cost catalysts is necessary and desirable for their practical application. In this communication, we exploited such a catalyst by anchoring singleCo(II) sites on g-C3N4, which was firstly achieved by the pyrolysis of ultrathin cobalt metal-organic framework (MOF) nanosheets (also called metal-organic layers; MOLs) during the process of g-C3N4 formation. Benefitting from the confinement effect of MOL matrix and the close contact between MOLs and g-C3N4 precursor, the Co(II) sites can be homogeneously and atomically dispersed on the surface of g-C3N4 during the process of g-C3N4 formation. Impressively, this photocatalyst possesses excellent catalytic performance for photochemical CO2-toCO conversion, with the CO evolution rate as high as 464.1 mu mol g(-1) h(-1), 3 and 222 times higher than those of using bulky Co-MOF and CoCl2 as the cobalt sources, respectively. This work paves a new way to develop the cost-effective photocatalysts containing single-atom sites for clean energy production.