Construction of NiAl-LDH/BiOBr type-II heterojunction to drive efficient CO2 photoreduction under visible light

Constructing heterostructures is an effective method for enhancing photocatalytic efficiency. Herein, a two-dimensional (2D)/2D heterojunction of NiAl-LDH/BiOBr with a built-in electric field (BIEF) was firstly synthesized. The photocatalytic efficiency of CO 2 reduction was assessed under visible light. And the findings revealed that the composite with 10 wt% NiAl-LDH demonstrated the highest CO 2 photoreduction performance, yielding a rate of 10.7 μmol·g −1 ·h −1 for CO generation, which was 21.4 and 4.3 times higher than that of pure NiAl-LDH and BiOBr. The heterojunction of the sample was type-II heterojunction with the analysis of XPS, band structures, and in-situ XPS. Photoluminescence (PL) and electrochemical tests demonstrated that the type-II heterojunction between NiAl-LDH and BiOBr efficiently enhanced the separation and transfer of electrons and holes, consequently boosting the photocatalytic performance. Besides, in-situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS) was employed to reveal the reaction intermediates of CO 2 . This work provides experimental approaches and theoretical development of nanocomposite for photoreduction of CO 2 .