Bio-Inspired Polydopamine: A Versatile and Powerful Platform for Covalent Synthesis of Molecular Sieve Membranes

摘要

Inspired by the bioadhesive ability of the marine mussel, a simple, versatile, and powerful synthesis strategy was developed to prepare highly reproducible and permselective molecular sieve membranes by using polydopamine as a novel covalent linker. Attributing to the formation of strong covalent and noncovalent bonds, ZIF-8 nutrients are attracted and bound to the support surface, thus promoting the ZIF-8 nucleation and the growth of uniform, well intergrown, and phase-pure ZIF-8 molecular sieve membranes. The developed ZIF-8 membranes show high hydrogen selectivity and thermal stability. At 150 ℃ and 1 bar, the mixture separation factors of H_2/CO_2, H_2/N2, H_2/CH_4, and H_2/C_3H_8 are 8.9, 16.2, 31.5 and 712.6, with H_2 permeances higher than 1.8 × 10~(-7) mol·m~(-2)·s~(-1)·Pa~(-1), which is promising for hydrogen separation and purification.