Highly dispersive and ultrasmall PdCu alloy anchored on PAA-grafted carbon nanotube as electrocatalysts for rechargeable zinc−air batteries

The study of electrocatalysis for oxygen reduction reaction (ORR) on non-platinum electrodes has attracted widespread interest. Herein, we demonstrate the exceptional electrocatalytic performance of PdCu alloy nanoparticles (NPs) supported on carbon nanotube (CNT) modified with grafted organic polymers in the oxygen reduction reaction (ORR). Among various bimetallic combinations, CNT- g -PAA-Pd 3 Cu 1 showed the best ORR activity, with the composite material significantly favoring the 4-electron transfer process, indicating strong selectivity. The Pd 3 Cu 1 electrocatalyst outperformed the traditional Pt/C catalysts in terms of half-wave potential (0.902 V), limiting current density (5 mA cm −2 ), and Tafel slope (42.95 mV·dec −1 ) in the ORR. The rechargeable zinc-air batteries (ZABs) made from these composite materials exhibited significant peak power density (230.8 mW cm −2 ) and high specific capacity (558 mAh·g −1 ). This work provides a strategy for designing efficient electrocatalysts for use in energy conversion and storage applications. • A ternary hybrid CNT- g -PAA/PdCu electrocatalyst is fabricated for Zinc–Air Batteries. • Ultrafine PdCu alloy NPs are densely and uniformly anchored on PAA-grafted CNTs. • The CNT- g -PAA/Pd 3 Cu 1 exhibits a high half-wave potential and a low Tafel slope. • The ZAB demonstrates exceptional peak power density and high specific capacity.