Affiliation:
1. State Key Laboratory of Urban Water Resource and Environment School of Chemistry and Chemical Engineering Harbin Institute of Technology 150001 Harbin China
2. School of Materials Science and Engineering China University of Petroleum (East China) 266580 Qingdao China
Abstract
AbstractSub‐nanoporous membranes with ion selective transport functions are important for energy utilization, environmental remediation, and fundamental bioinspired engineering. Although mono/multivalent ions can be separated by monovalent ion selective membranes (MISMs), the current theory fails to inspire rapid advances in MISMs. Here, we apply transition state theory (TST) by regulating the enthalpy barrier (ΔH) and entropy barrier (ΔS) for designing next‐generation monovalent cation exchange membranes (MCEMs) with great improvement in ion selective separation. Using a molecule‐absorbed porous material as an interlayer to construct a denser selective layer can achieve a greater absolute value of ΔS for Li+ and Mg2+ transport, greater ΔH for Mg2+ transport and lower ΔH for Li+ transport. This recorded performance with a Li+/Mg2+ perm‐selectivity of 25.50 and a Li+ flux of 1.86 mol ⋅ m−2 ⋅ h−1 surpasses the contemporary “upper bound” plot for Li+/Mg2+ separations. Most importantly, our synthesized MCEM also demonstrates excellent operational stability during the selective electrodialysis (S‐ED) processes for realizing scalability in practical applications.
Funder
National Natural Science Foundation of China