Performance of x Mg3Al1-LDH@ZIF-8 in High Efficiency Electrocatalytic Reduction of CO2 to CO

Langmuir. 2024 Nov 22. doi: 10.1021/acs.langmuir.4c03147. Online ahead of print.

Abstract

This study involves the preparation of the precursor of magnesium aluminum layered double hydroxide (Mg3Al1-LDH) through a hydrothermal synthesis method. Subsequently, altering the loading amount of the precursor to synthesize a series of nanomaterials (xMg3Al1-LDH@ZIF-8, x = 0.2, 0.5, and 0.8) composite with zeolitic imidazolate framework-8 (ZIF-8). The investigation delves into the electrocatalytic performance of the material in the electrochemical reduction of CO2 (CO2RR) for the production of CO. The electrocatalyst is subjected to analysis through various techniques such as XRD, XPS, Raman, FTIR, SEM, EDS, TEM, BET, etc., to examine the elemental composition, microscopic morphology, and surface area with pore size. The electrochemical performance of the materials is tested and analyzed using an electrochemical workstation and gas chromatograph. The research findings reveal that the electrocatalyst with a loading amount of 0.5 g, denoted as 0.5Mg3Al1-LDH@ZIF-8, exhibits a well-defined rhombic dodecahedral morphology with a surface-attached layered structure. This structure, characterized by relatively strong interactions, provides abundant active sites for the reaction, consequently demonstrating superior electrochemical performance. The Faradaic efficiency (CO FE) for CO2RR to produce CO reaches a maximum of 88.08% at -1.5 V vs. RHE. Maintaining a constant applied voltage at -1.4 V vs. RHE ensures stability for up to 4 h.