Periodic Reporting for period 1 - Graphene Membranes (Ultrapermeable Atomically-Thin Membranes for Molecular Separations)
Reporting period: 2015-10-01 to 2017-09-30
Graphene membranes can provide extremely fast permeation due to their atomically-thin structure, promising very high energy efficiencies for many industrial separation processes, from gas separation to water desalination. However, technical problems regarding their scalability and controlled pore sizes at nm-scale hindered their applications. This project addresses these two particular problems and aims at obtaining cm-scale graphene membranes, as well as demonstrating controllable molecular sieving.
In brief, the project was aimed at demonstrating both scalability (cm-scale) and functionality (molecular sieving). The experimental setups and methods developed from scratch at the host institution, yielding graphene membranes with 10-nm pores at sub-mm2 areas scattered around a cm-scale substrate, as well as 5-nm-pores at smaller membrane areas.
1. A new transfer method based on photoresist sacrificial layers has been developed, enabling easy removal of the sacrificial layer, compared to the conventional PMMA layers.
2. A new technique based on e-beam-induced deposition of Pt around the pore rims has been developed, reducing the pore diameters down to 5 nm.
2. A new technique based on e-beam-induced deposition of Pt around the pore rims has been developed, reducing the pore diameters down to 5 nm.