Large-area graphene-nanomesh/carbon-nanotube hybrid membranes for ionic and molecular nanofiltration
Nanoporous two-dimensional materials are attractive for ionic and molecular nanofiltration but limited by insufficient mechanical strength over large areas. We report a large-area graphene-nanomesh/single-walled carbon nanotube (GNM/SWNT) hybrid membrane with excellent mechanical strength while fully capturing the merit of atomically thin membranes. The monolayer GNM features high-density, subnanometer pores for efficient transport of water molecules while blocking solute ions or molecules to enable size-selective separation. The SWNT network physically separates the GNM into microsized islands and acts as the microscopic framework to support the GNM, thus ensuring the structural integrity of the atomically thin GNM. The resulting GNM/SWNT membranes show high water permeance and a high rejection ratio for salt ions or organic molecules, and they retain stable separation performance in tubular modules.
To realize the commercial potential of graphene, for instance for wearable electronics, it is necessary to develop reliable, cost-effective and facile processes for the industry-scale fabrication of graphene-based devices. A novel solution involves the synthesis of high-performance stretchable graphene ink using a facile, scalable, and low-cost laser induction method for the synthesis of the graphene component. This also is the first example of using laser-induced graphene in the form for a powder preparation of graphene-based inks and subsequently for use in screen-printing of stretchable micro-supercapacitors.