To reduce CO2 in the atmosphere, many approaches have been developed. Electrochemical CO2 reduction (ECO2RR) is one of the methods that can valorize existing CO2 and convert them into valuable products. Copper is an outstanding electrocatalysts for ECO2RR because of its ability to form various carbon products, such as ethylene, methane, formate, methanol, and so on. However, the selectivity toward a specific product has yet to be improved. Here, we explored a new type of coating, metal phenolic network (MPN), which is a 2D porous framework formed by the chelation of metal ions and polyphenol groups. We combine these coatings with copper nanoparticles to form core-shell structures. The coating is aimed at assisting with the selectivity of certain products. We have done some characterizations such as transmission electron microscopy (TEM), fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). We further compared different MPN coatings to come up with a general idea on which coating is best at selecting targeted products. Electrochemical analysis and products quantification by nuclear magnetic resonance (NMR) were performed. Our modifying method with MPN coatings is demonstrating a new way to optimize the selectivity of copper nanoparticle electrocatalysts with low cost and simple synthesis by taking advantage of self-assembling property of MPNs.
