'Carbon sponge' soaks up coal emissions

Posted by Kate Taylor

Emissions from coal power stations could be cut drastically by a new, energy-efficient material that adsorbs large amounts of carbon dioxide, then releases it when exposed to sunlight.

A team of scientists has discovered a new photosensitive metal organic framework (MOF) - a class of materials known for their exceptional capacity to store gases. As a result, they say, they've created a powerful and cost-effective new tool to capture and store, or potentially recycle, carbon dioxide.

By using sunlight to release the stored carbon, the new material overcomes the problems of expense and inefficiency associated with current, energy-intensive methods of carbon capture, says the team. Associate Professor Bradley Ladewig of the Monash Department of Chemical Engineering said the MOF was an exciting development in emissions reduction technology.

"For the first time, this has opened up the opportunity to design carbon capture systems that use sunlight to trigger the release of carbon dioxide," says associate Professor Bradley Ladewig of Monash University. "This is a step-change in carbon capture technologies."

MOFs are clusters of metal atoms connected by organic molecules. Thanks to their extremely high internal surface area - you could cover an entire football field with a single gram - they can store large volumes of gas.

"The MOF can release the adsorbed carbon dioxide when irradiated with light found in sunlight, just like wringing out a sponge," says PhD student Richelle Lyndon.

"The MOF we discovered had a particular affinity for carbon dioxide. However, the light responsive molecules could potentially be combined with other MOFs, making the capture and release technology appropriate for other gases."

The researchers now plan to optimise the material to make it efficient enough for an industrial environment.