IEEE Spectrum August 10, 2018
Researchers in China have demonstrated that by dispersing tellurium nanoparticles into water, the water evaporation rate is improved by a factor of three under solar radiation. This makes it possible to increase the water temperature from 29 degrees to 85 degrees Celsius within 100 seconds. The Te nanoparticles perform like a plasmonic nanoparticle when it is smaller than 120 nanometers and then as a high-index all-dielectric nanoparticle when those nanoparticles are larger than 120 nm as they have a wide size distribution (from 10 to 300 nm). This enhanced absorption can cover the whole solar radiation spectrum. When it is excited by sunlight, the excitation energy is transferred entirely to the carriers pushing the carriers out of equilibrium and into special states of momentum with higher temperatures. Because of the unique optical duality, Te nanoparticles have other applications for the technology… read more. Open Access TECHNICAL ARTICLE
Thermal images show the difference in solar radiation absorbed by a bare silicon wafer (left) and a Te nanoparticle (right). Credit: Science Advances