Broad Range Energy Absorption Enabled by Hydrogenated TiO2 Nanosheets: from Optical to Infrared and Microwave
Effecient energy harvesting is critical in developing various future clean energy sources and technologies from our ultimate clean energy source – the sun, which covers a broad range of photon energies ranging from ultraviolet, to visible, infrared, and microwave regions. Absorption is the first key step to the uptake of the solar energy for various energy conversions and utilizations. Materials with broadrange electromagentic interaction are therefore highly desirable. Here, we demonstrate that such a broad range energy absorption from visible light to microwave regions can be achieved with hydrogenated TiO2 nanosheets. A large near-infrared and visible-light absorption (> 60%), a broad mid-IR absorption, and a highly efficient absorption in the microwave region have been obtained with hydrogenated TiO2 nanosheets. On the contrary, barely any absorption is observed for pristine TiO2 nanosheets in these regions. Therefore, this study shows that with such high absorption across such a broad energy range, hydrogenated TiO2 nanosheets obviously have the large capability in absorbing the solar energy across a broad energy region, which can be potentially useful for various photo-, photoelectro-, photochemical- applications, such as semiconductor devices, photocatalysis, photovoltaics, infrared detection, microwave communication.