posted on 2021-04-19, 16:09authored byTian-Ci Zhuo, Yang Song, Gui-Lin Zhuang, Lu-Ping Chang, Shuang Yao, Wei Zhang, Ye Wang, Ping Wang, Wenbin Lin, Tong-Bu Lu, Zhi-Ming Zhang
It
is highly desirable to achieve solar-driven conversion of CO2 to valuable fuels with controlled selectivity. The existing
catalysts are mainly explored for CO production but rarely for formate
generation. Herein, highly selective photoreduction of CO2 to formate (99.7%) was achieved with a high yield of 3040 μmol
g–1 in 10 h by hierarchical integration of photosensitizers
and monometallic [bpy-Cu/ClX] (X = Cl or adenine) catalysts into a
stable Eu-bpy metal–organic framework. However, replacing X
with pyridine in [bpy-CuCl/X] significantly reduced formate production
while increasing the CO yield to 960 μmol g–1. Systematic investigations revealed that the catalytic process is
mediated by the H-bond synergy between Cu-bound X and CO2-derived species, and the selectivity of HCOO– can
be controlled by simply replacing the coordination ligands. This work
provides a molecularly precise structural model to provide mechanistic
insights for selectivity control of CO2 photoreduction.