Scientists in South Korea have managed to develop simultaneous electricity generation alongside the filtration of wastewater

A novel membrane using a combination of a water filtration membrane and conductive polymer, has led to water quality improvement and continuous electricity generation using a simple operation method.

The purification of various water resources, such as rain, seawater, groundwater, river water, sewage, and wastewater, into potable or usable water is a high-energy process.

So, what if electricity could be generated during the water purification process?

In the spotlight, a domestic research team has developed a multifunctional membrane that can simultaneously generate electricity while purifying wastewater into drinking water.

The Korea Institute of Science and Technology (KIST) has announced that Dr Ji-Soo Jang’s team from the Electronic Materials Research Center and Professor Tae-Gwang Yoon’s team from the Department of Materials Science and Engineering, Myongji University have jointly developed an advanced membrane that can simultaneously provide drinking water and generate continuous electricity from various water resources, such as sewage/ wastewater, seawater, and groundwater.

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generates electricty

The ‘sandwich-like’ membrane is composed of a porous membrane that filters water at the bottom and a conductive polymer that generates electricity at the top. The membrane is designed to purify wastewater by controlling the direction of the water flow.

Water flowing perpendicularly to the membrane generates direct current by the movement of ions along the horizontal direction.

The membrane can reject more than 95% of the contaminants of sizes less than 10nm (one hundred-millionth of a metre). Hence, microplastics and heavy metal particles in wastewater can be removed, and continuous electricity can be generated for more than three hours with only 10µl (microlitre) of water.

Since the membrane can be manufactured using a simple printing process without size restrictions, it has a high potential to be commercialised due to low manufacturing costs and processing time.

The research team is currently conducting follow-up research to generate electricity while improving the water quality of wastewater to the level of drinking water by developing the membrane for an actual factory.

KIST’s Dr Ji-Soo Jang said: “As a novel technology that can solve water shortage problems and produce eco-friendly energy simultaneously, it also has great potential applications in the water quality management system and emergency power system.”

Image: Schematic illustration for the operation of the electricity generation and water purification membrane developed by KIST-Myongji University joint research team. © Korea Institute of Science and Technology.