Ultrathin NiAl-Layered Double Hydroxides Grown on 2D Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene to Construct Core–Shell Heterostructures for Enhanced Photocatalytic CO<sub>2</sub> Reduction
Shuang Zhao, Deng Pan, Qian Liang, Man Zhou, Chao Yao, Song Xu, Zhongyu Li
Abstract
Photocatalytic CO2 reduction into renewable fuels by sustainable and clean solar energy can be considered as an ideal option to decrease the atmospheric CO2 level and fulfill the energy requirements. Layered double hydroxides (LDHs) with high surface area, tunable composition as well as exposed active sites have received enormous attention for photocatalytic CO2 reduction. Herein, a novel NiAl-LDH/Ti3C2Tx nanosheet (NiAl-LDH/TNS) with a core–shell structure was synthesized via an in situ hydrothermal method, and 2D NiAl-LDH coupled with the 2D Ti3C2Tx nanosheet to form a Schottky junction can suppress the back-diffusion of electrons and facilitate the transfer of charge carriers. Benefiting from the feature, the optimized sample with the additive Ti3C2Tx amount of 75 mg (NiAl-LDH/TNS-75) has the photocatalytic CO2 reduction conversion rate of CO (2128.46 μmol h–1 g–1) with the selectivity of CO (90.2%) under visible-light irradiation, which is about 8.6 times higher than that of pristine NiAl-LDH. This work provides a new insight into the construction of novel 2D semiconductor photocatalysts.