CNT nanoengineering for thermally stable selective solar absorption

Solar thermal electricity generation is an appealing green concept, which the efficiency enhancement requires the development of appropriate solar absorbers using an up-scalable processing technique. Here, we report on the nanoengineering of carbon nanotubes (CNT) as an approach to design high-performance solar absorbers using oxide materials in a core/shell architecture. Gas-phase synthesis is deployed for the growth of modified CNT cores with infra-red reflecting and low refractive index shell layers. The designed coating fully benefits from the high absorbance of CNTs and the infrared-reflecting properties of Al-doped ZnO irrespective of the nature of the underlying substrate. The nano-engineered CNT-metal oxide design withstands extended exposure to 1000 K.