On the boil

Researchers at Rensselaer Polytechnic Institute have shown that by adding an invisible layer of nanomaterials to the bottom of a metal vessel, an order of magnitude less energy is required to bring water to boil.

This increase in efficiency could have a big impact on cooling computer chips, improving heat-transfer systems and reducing costs for industrial boiling applications.

'Like so many other nanotechnology and nanomaterials breakthroughs, our discovery was completely unexpected,' said Nikhil A Koratkar, associate professor in the Department of Mechanical, Aerospace, and Nuclear Engineering at Rensselaer.

'The increased boiling efficiency seems to be the result of an interesting interplay between the nanoscale and microscale surfaces of the treated metal.'

Bringing water to a boil and the related phase change that transforms the liquid into vapour requires an interface between the water and air. In the example of a pot of water, two such interfaces exist: at the top where the water meets air; and at the bottom where the water meets tiny pockets of air trapped in the microscale texture and imperfections on the surface of the pot.