Dual-functional conductive nanofilm absorber

Converting solar energy by to other forms of energy has attracted a lot of interest from academy to industry. However, the overall utilization efficiency of solar energy is inferior due to the limited effective solar spectrum range. Here, in order to utilize the broadband solar spectrum more efficiently, a novel hybrid absorber structure was proposed, which consists of a four-layer planar nanofilm with dual functions of heat absorption and photocatalysis. The average absorption in the visible range is larger than 0.95, and in the near-infrared spectral region, the average absorption is still larger than 0.85. The overall absorption of the absorber is over 0.86, while the thermal emittance is lower than 0.04, which can lead to remarkable thermal utilization efficiency. Moreover, the full range of the solar irradiance can be utilized by incorporating the photocatalytic TiO₂ layer into the absorber, which is active in the ultraviolet spectral range. In addition to the broadband spectral usage, the virtues of inexpensiveness and environmental friendliness make it a facile alternative to be applied in solar energy transformation.