A system that yields the benefits of electric power production and carbon dioxide (CO₂) capture has been engineered by researchers in Australia. A small proof-of-concept nanogenerator consumes the greenhouse gas and produces power by reliance on ion separation technology.

The two-component device is assembled by embedding a polyamine gel that is already used by industry boron nitrate structure only a few atoms thick in a hydrogel which is 90% water. The polyamine gel is widely used to absorb CO₂ and the boron nitrate element serves to generate positive and negative ions. These materials were cut into 4 cm discs and rectangles and tested in a sealed box pumped full of the gas. The design exploits CO₂ adsorption-induced ion releasing and ion separation within hydrogel channels to facilitate power generation.

“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 which can be amplified into electricity to power light bulbs or any electronic device,” explained the researchers from the University of Queensland and Monash University.

The technology absorbs carbon dioxide and generates electricity. Source: University of Queensland

A stable output voltage of 5 V was generated after 50 nanogenerators were integrated to amplify system production. This proved sufficient to power a light-emitting diode with an operating voltage of 1.6 V and forward current of 1 mA. The CO₂-adsorption energy harvesting framework described in Nature Communications could spur development of alternative carbon-negative power generation solutions and enhance the efficacy of existing carbon capture and utilization technologies.