Technology Overview

This technology relates to an ion selective membrane with a device and method for generating electricity from two solutions with different chemical potentials.

The membrane’s layers are intrinsically uncharged, atomically smooth, and with a critical dimension as small as 0.3 nm. While the charge-free and smooth walls enable faster movement of the ions, the increased mobility also enhances ionic selectivity of the membrane. The mobility of the ions can be further adjusted by altering the material make-up of the layer such as graphene and boron nitride (or any other 2D material).

To generate electricity, the membrane is placed between two chambers with solutions of different chemical potentials. Each solution is also connected to two electrodes joined by a generator load. As molecules pass through the membrane, this creates an osmotic current and potential that generates electricity which is then collected by the generator load. The membrane’s performance can be modified to increase selectivity or tuned to be more hydrophilic/hydrophobic if necessary. Two sets of membranes with opposite charge selectivity can also be used to form part of an electrodialysis (ED) system.

The technology provide is currently looking for licensing partners to commercialise this technology.

Technology Features, Specifications and Advantages

• 2 layered graphene-based membrane
• Spacer with a range of 1 µm² to 1 mm²
• Separation of ions for osmotic power generation
• A charge-free, atomically smooth membrane for nanofiltration and blue energy generation
• 30 x cheaper and 1,000 times more powerful than existing ion exchange membranes with the same surface area
• High ionic and molecular selectivity while retaining the ultra-high water flux of graphene membranes

Potential Applications

With rapid industrialisation and increases in applications, the demand for membranes has risen. Industries such as chemical, pharmaceutical and wastewater treatment demand for quality membranes that fit different specifications. The market for membranes was estimated to be US$8.92 billion in 2020, and to grow at a CAGR of 10.35% to reach US$14.6 billion by 2025.

Furthermore, as global energy consumption increases—the search for sustainable and renewable energy sources has intensified as fossil fuels are increasingly depleted. One such potential energy source is osmotic power also known as blue energy which relies on osmosis via membranes. However, conventional membranes used for the process are expensive and have low power density.

Customer Benefit

• Can be combined with an electrodialysis system for energy storage as a battery
• Applicable in biofiltration due to chemical inertness of nanocavities