ZSM-5 zeolite incorporated flow battery membranes with regulated pore channels for high proton conduction

Fast proton conduction plays an essential role in ion conductive membranes (ICMs) for energy conversion and storage technologies, but the demand for low reactive species permeation always limits further enhancement in proton transport rate. Herein, an ICM incorporating ZSM-5 zeolite with optimized physicochemical property of pore channels was developed to achieve highly conductive ion transport via regulating the silicon-aluminum atomic (Si/Al) ratio of ZSM-5. Benefiting from the regulation of pore channels of zeolites, the proton conductivity of the pristine membrane was remarkably improved to 1.7-fold. As expected, the optimized membrane exhibited outstanding voltage efficiency (VE) of 85.7% and energy efficiency (EE) of 85.1% at 120 mA/cm², which is considerably better than pure polymer membrane (VE of 80.5% and EE of 79.4%) and commercial Nafion 212 (VE of 81.3% and EE of 77.4%) membrane, respectively.