Multi-defect Pd-based catalyst doped with rare earth element La for ethanol-assisted energy-saving hydrogen production

Abstract

Replacing the oxygen evolution reaction (OER) at the anode in water electrolysis with the more thermodynamically favourable ethanol oxidation reaction (EOR) offers an innovative approach to achieving efficient and energy-saving hydrogen production. Herein, we successfully synthesised PdLa bimetallene with a multi-defect crimped perforated structure using a one-step wet chemical method, achieving remarkable catalytic performance in both EOR and hydrogen evolution reaction (HER). The established two-electrode system of EOR & HER realises a current density of 100 mA cm⁻² at 0.61 V, which is significantly lower by 0.95 V compared to that in case of electrochemical water splitting. Meanwhile, the introduction of the rare earth element (RE) La endows PdLa bimetallene with better catalytic performance compared to Pd metallene and Pd black. The effect of La addition on the catalytic performance is confirmed using density functional theory (DFT) calculations. This study provides a new method for ethanol-assisted energy-saving hydrogen production, and expands the application of REs in the hydrogen production process to a certain extent.