2D Metal-Organic Framework Derived CuCo Alloy Nanoparticles Encapsulated by Nitrogen-Doped Carbonaceous Nanoleaves for Efficient Bifunctional Oxygen Electrocatalyst and Zinc-Air Batteries.

Abstract

The development of efficient bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) still remains a challenge in a wide range of renewable energy technologies. Herein, CuCo alloy nanoparticles encapsulated by nitrogen-doped carbonaceous nanoleaves (CuCo-NC) have been synthesized from a Cu(OH)2 /2D leaf-like zeolitic imidazolate framework (ZIF-L)-pyrolysis approach. Leaf-like Cu(OH)2 is first prepared by the ultrasound-induced self-assembly of Cu(OH)2 nanowires. The efficient encapsulation of Cu(OH)2 in ZIF-L is obtained owing to the morphology fitting between the leaf-like Cu(OH)2 and ZIF-L. CuCo-NC catalysts present superior electrocatalytic activity and stability toward ORR and OER over the commercial Pt/C and IrO2 , respectively, which are further used as bifunctional oxygen electrocatalysts in Zn-air batteries and exhibit impressive performance, with a high peak power density of 303.7 mW cm-2 , large specific capacity of up to 751.4 mAh g-1 at 20 mA cm-2 , and a superior recharge stability.