Scientists at UNSW have come up with yet another application for the “super material” graphene – this time using it as a dessicant that has the potential to revolutionise moisture control in applications from electronics to air conditioning.
The new super dessicant, made from graphene oxide, has been shown to be twice as absorbent as the industry standard, silica gel.
A team led by Dr Rakesh Joshi of the UNSW School of Materials Science and Engineering has developed the material, and a study outlining its performance in laboratory tests has been published in the journal Chemical Science.
“This is a stable new material that shows significant gains in adsorption capacity over conventional desiccants,” says Dr Joshi.
“One novel application we are investigating is the integration of the desiccant into inner soles of shoes to control odour and moisture. As the moisture could be released back into the atmosphere using an ordinary household device like a warm oven, shoes could be recharged regularly to keep them constantly fresh.”
The key to the material’s extraordinary adsorption and desorption rates lies in the high capillary pressure in the grapheme oxide laminates and tunnel-like wrinkles on their surfaces – processes which had not previously been understood.
Now, the ability to fine-tune the spaces between the layers of graphene oxide as desired will allow the development of customised dessicants to control moisture across multiple applications.
The new desiccant can also discharge moisture at low temperatures, enabling it to be used over and over again without expending excessive energy. By contrast, the heating required to regenerate conventional desiccants is often considered prohibitively expensive.