A nanoporous carbon membrane has been fabricated to generate electric power by reverse electrodialysis. High ionic conductivity and output power density positions the membrane designed by researchers from Leiden University (The Netherlands) and Ulm University (Germany) as a suitable component for nanofluidics, A crosslinked membrane transferred onto a silicon wafer after annealing. Source: Liu, X., He, M., Calvani, D. et al.membrane separation and nanopore applications.

A 2 nm thick membrane was synthesized by applying a polycyclic aromatic hydrocarbon monomer to the air/water interface. The hydrocarbon monolayer is transferred onto a copper substrate and annealed under vacuum at 550° C to produce a stable, porous crosslinked membrane tailored for enhanced potassium ion permeability.

The device described in Nature Nanotechnology was demonstrated to generate electricity from mixing artificial seawater and river water via reverse electrodialysis. The carbon membrane offers a high short-circuit current with an output power density of 67 W/m², which is about two orders of magnitude beyond that of available ion-exchange membranes and prototype nanoporous membranes.