ZnO electrocatalyst integrated onto carbon paper for efficient non-aqueous Li–O2 batteries

Abstract

The development of high-performance lithium–oxygen (Li–O₂) batteries is hindered by challenges including high overpotential and limited cycle life. In this paper, we report the cost-effective and scalable synthesis of a ZnO electrocatalyst directly integrated onto carbon paper via a simple dipping and thermal treatment method. The resulting ZnO-on-carbon composite (ZnO on P50) was employed as the cathode in a non-aqueous Li–O₂ battery. Comprehensive physicochemical characterizations, including XPS, FE-SEM, and TEM, confirmed the successful incorporation and uniform dispersion of ZnO nanoparticles within the carbon matrix. Electrochemical evaluations revealed that the ZnO-based cathode reduced overpotential during charge–discharge cycles and improved energy efficiency by approximately 6.3% over 40 cycles compared to pristine carbon paper (P50). Ex situ XRD and SEM analyses further validated the formation and decomposition of Li₂O₂ during cycling and suggested enhanced reaction uniformity owing to the catalytic role of ZnO. These findings demonstrate that in situ-grown ZnO offers a promising, low-cost strategy for improving the energy efficiency of Li–O₂ batteries.