Large‐Scale, Vertically Aligned 2D Subnanochannel Arrays by a Smectic Liquid Crystal Network for High‐Performance Osmotic Energy Conversion

Abstract

The osmotic energy, an abundant renewable energy source, can be directly converted to electricity by nanofluidic devices with ion‐selective membranes. 2D nanochannels constructed by nanosheets possess abundant lateral interfacial ion‐exchange sites and exhibit great superiority in nanofluidic devices. However, the most accessible orientation of the 2D nanochannels is parallel to the membrane surface, undoubtedly resulting in the conductivity loss. Herein, we first demonstrate vertically aligned 2D sub‐nanochannel arrays self‐assembled by a smectic liquid crystal (LC) network that exhibit high‐performance osmotic energy conversion. The 2D sub‐nanochannel arrays are fabricated by in‐situ photo‐polymerization of monomers in the LC phase. The as‐prepared membrane exhibits excellent water‐resistance and mechanical strength. The 2D sub‐nanochannels with excellent cation selectivity and conductivity show high‐performance osmotic energy conversion. The power density reaches up to about 22.5 W/m2 with NaCl solution under a 50‐fold concentration gradient, which is among with ultrahigh power density. This membrane design concept provides promising applications in osmotic energy conversion.This article is protected by copyright. All rights reserved