Ultrathin PdBiRh trimetallene for energy-saving polyethylene terephthalate-derived ethylene glycol electrooxidation coupled carbon dioxide electroreduction

The feasibility of carbon dioxide reaction reduction (CO2RR) technology suffers from the sluggish reaction kinetics, high overpotential, low product selectivity, and high energy consumption of oxygen evolution reaction (OER) at the anode. Herein, ultrathin PdBiRh trimetallene (PdBiRh TML) was achieved by one-pot synthesis, which revealed a high activity for both polyethylene terephthalate-derived ethylene glycol oxidation reaction (EGOR) and CO2RR. The incorporation of Bi and Rh atoms could efficiently modulate the electronic structure of the Pd substrate and regulate the adsorption mode of reaction intermediates, resulting in high activity and C2 product selectivity of PdBiRh TML for both EGOR and CO2RR. Consequently, a symmetrical PdBiRh TML||PdBiRh TML electrolyzer was applied in the EGOR-coupled CO2RR system, which could operate at a total cell voltage of only 0.59 V, much lower than the conventional CO2RR system with anodic OER (1.49 V). Meanwhile, the Faraday efficiency for the C2 pathway (FEC2) of anodic EGOR could reach 91.19% and the FEC2 of cathodic CO2RR could reach 55.48% in this coupled system, revealing an energy-saving and efficient method for the co-production of glycolic acid at the anode and C2 products of CO2RR at the cathode.