COF-5/CoAl-LDH Nanocomposite Heterojunction for Enhanced Visible-Light-Driven CO2 Reduction.

Photocatalytic conversion of CO 2 into value-added chemical fuels is an attractive route to mitigate global warming and the energy crisis. Reasonable designing optical properties and electronic behavior of the photocatalyst are essential to improve their catalytic activity. Herein, the 1D/2D heterojunction by directly in-situ synthesis of the COF-5 colloid on the surface of CoAl-LDH is used as the prospective photocatalysts for CO2 reduction. COF-5/CoAl-LDH nanocomposite achieves 265.4 μmol g -1 of CO with 94.6% selectivity over CH4 evolution in 5 h under visible light irradiation, which exhibits 4.8 times and 2.3 times higher than those of COF-5 colloid and CoAl-LDH, respectively. The enhanced catalytic activity is derived from the increased visible-light activity and the construction of type II-2 heterojunction, which greatly optimizes visible light harvesting and accelerates the efficient separation of the photoinduced holes and electrons. This work provides the way for the rational design of heterojunction catalysts in photocatalytic CO2 reduction.