In-situ growth of CuO/Cu nanocomposite electrode for efficient CO2 electroreduction to CO with bacterial cellulose as support

Abstract

Bacterial cellulose (BC) with large surface area and hydrophilic surface property is considered to be a good potential porous substrate for the deposition of active materials for catalysis, but lacks electrical conductivity for desired electrocatalysis application. By applying an in-situ chemical reduction, we here report a self-standing, BC-supported catalyst electrode of highly dispersed Cu and CuO nanocomposites (CuO/Cu4:3@BC) for catalyzing efficient CO2 electroreduction to CO. The inherent three-dimensional web-like porous structure of the BC substrate is sustained without further carbonization of the electrode. Compared to the conventional carbon paper-supported CuO/Cu composite catalysts, the as-prepared CuO/Cu4:3@BC electrode demonstrates an outstanding charge transport property and higher current density for CO2 reduction, owing to superiority of the web-like porous structure of the BC substrate with more accessible active sites to electrolytes and faster transfer of reactants and products. Therefore, the architecturally arranged CuO/Cu composite catalysts of the CuO/Cu4:3@BC electrode offer unique structural advantages of good ion and charge transport, promoting the catalytic kinetics for the conversion of CO2 to CO. The resulting electrode affords CO with a faradaic efficiency of 53 % at a small overpotential of 490 mV, and a durable activity over 40 h.