Construction of highly active Pt–Ag flexible composite electrodes and investigation of electrocatalytic performance for ethylene glycol oxidation

Abstract

Ethylene glycol (EG), the predominant compound derived from the alkaline decomposition of polyethylene terephthalate (PET)-based waste, can be electrocatalytically upgraded into value-added chemical products accompanied by hydrogen (H2) generation, which provides an effective strategy for resource utilization of plastic waste. Herein, a novel flower-like PtAg-AgNWs flexible electrode is fabricated to catalyze the electrochemical oxidation of EG. Electrochemical measurements reveal that at a current density of 20 mA cm−2, the required potential of the as-prepared flexible electrode for ethylene glycol oxidation reaction (EGOR) decreases by 840 mV compared with that for oxygen evolution reaction (OER), thereby markedly lowering power demand during electrolysis and synchronously realizing the directional oxidation of EG into glycolic acid (GA). Furthermore, kinetic analysis demonstrates that the Tafel slope of the PtAg-AgNWs electrode is only 50.5 mV dec−1, which fully proves that the as-prepared flower-like PtAg-AgNWs flexible composite electrode possesses excellent catalytic activity and reaction kinetics for the electrocatalytic oxidation of EG.