14 February 2015

Ag Nanowires to Improve Thermal Comfort in Clothes

Researchers at Stanford University, lead by Prof. Yi Cui have proposed a new idea to improve the thermal insulation of our clothes and even being able to increase their temperature to fit our comfort. About half of the global energy consumption is spent in indoor heating. Most of efforts to reduce this are focused on improving building insulation. However, the Stanford group proposed a different approach targeting at our own clothes. They proved that coating clothing with a mesh of silver nanowires provides better insulation than regular clothes and also can be used to generate its own heat. 

(Concept and picture of the nanowires cloth at the left part. On the right top a glove with a S letter coated with the nanowires that remains colder than the rest of the non-coated glove in the IR camera picture at the bottom right. Image from Nano Letters)

Metals can reflect back the body heat more efficiently than fabrics, but they are hard and clothes require soft materials. For this reason they used metallic nanowires. Since metals conduct electricity, by means of a mini battery, a small current can be passed through the nanowire mesh producing heating by Joule effect. Their results can significantly contribute to change the way we heat our buildings and can be seen at Nano Letters