Asymmetric Air Cathode Design for Enhanced Interfacial Electrocatalytic Reactions in High‐Performance Zinc–Air Batteries. Issue 12 (19th February 2020)

• Record Type: Journal Article
• Authors: Yu, Jia; Li, Bo‐Quan; Zhao, Chang‐Xin; Liu, Jia‐Ning; Zhang, Qiang
• Is Part Of: Advanced materials. Volume 32:Issue 12(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-02-19
• Subjects: 3D multiphase interfaces -- air cathodes -- asymmetric architecture -- zinc–air batteries; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201908488
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: The rechargeable zinc–air battery (ZAB) is a promising energy storage technology owing to its high energy density and safe aqueous electrolyte, but there is a significant performance bottleneck. Generally, cathode reactions only occur at multiphase interfaces, where the electrocatalytic active sites can participate in redox reactions effectively. In the conventional air cathode, the 2D multiphase interface on the surface of the gas diffusion layer (GDL) inevitably results in an insufficient amount of active sites and poor interfacial contact, leading to sluggish reaction kinetics. To address this problem, a 3D multiphase interface strategy is proposed to extend the reactive interface into the interior of the GDL. Based on this concept, an asymmetric air cathode is designed to increase the accessible active sites, accelerate mass transfer, and generate a dynamically stabilized reactive interface. With a NiFe layered‐double‐hydroxide electrocatalyst, ZABs based on the asymmetric cathode deliver a small charge/discharge voltage gap (0.81 V at 5.0 mA cm −2 ), a high power density, and a stable cyclability (over 2000 cycles). This 3D reactive interface strategy provides a feasible method for enhancing the air cathode kinetics and further enlightens electrode designs for energy devices involving multiphase electrochemical reactions. Abstract : A 3D multiphase reactive interface strategy is proposed to enhance the reaction kinetics in the air cathode of a rechargeable zinc–air battery. As a proof of concept, an asymmetric air cathode is designed, which exhibits an increased amount of accessible active sites, accelerated mass transfer, and a dynamically stabilized reactive interface.