Turning CO₂ into Clean Energy at a Lower Carbon Capture Cost

Carbon dioxide has always been seen as a problem that needs to be solved, but what if this greenhouse gas becomes a sustainable resource that could help clean energy technologies?

Researchers Dr Zhuyuan Wang from UQ’s Dow Centre for Sustainable Engineering Innovation have built a generator that absorbs carbon dioxide (CO2) to make electricity. The carbon-negative power generator, published in the Nature Communications Journal, is a small proof-of-concept nanogenerator at a laboratory scale, at least for now. Still, developers think it could become an industrial-scale carbon capture method that generates electricity.

Dr Xiwang Zhang and his researchers at the University of Queensland have pioneered an innovative device capable of generating electricity by moving charged particles.

Dr Wang explains

“This nanogenerator is made of two components: a polyamine gel that is already used by industry to absorb CO₂ and a skeleton a few atoms thick of boron nitrate that generates positive and negative ions,” Dr Wang said.

“We’ve worked out how to make the positive ions much larger than the negative ions, and because the different sizes move at different speeds, they generate a diffusion current that can be amplified into electricity to power light bulbs or any electronic device.”

“In nature and the human body, ion transportation is the most efficient energy conversion—more efficient than electron transportation, which is used in the power network.”

Dr Wang is ecstatic about this discovery. “When we saw electrical signals coming out, I was very excited but worried I’d made a mistake,” Dr Wang said.

“I double-checked everything, and it was working correctly, so I started dreaming about changing the world using this technology. The two components were embedded in a hydrogel, which is 90 per cent water, cut into 4-centimetre discs and small rectangles and then tested in a sealed box pumped full of CO2. At present, we can harvest around 1% of the total energy carried intrinsically by gas CO2, but like other technologies, we will now work on improving efficiency and reducing cost.”

Following the success of the laboratory tests, the researchers suggest that the device could have two potential applications if scaled up.

First, it could serve as a portable electricity generator for small electronics. Second, it could be integrated into industrial carbon capture plants to generate electricity on a larger scale.

Read the study by clicking the link in the “Sources” section below.