DVD assisted titanium metasurface for solar energy perfect absorption and potential applications for local thermal antibacterial treatment.

A novel broadband solar absorber is numerically studied based on the commercial digital versatile disc (DVD). Refractory titanium (Ti) material is artificially coated onto the surface of the DVD, which then forms the plasmonic resonant metasurface. Spectral average absorption reaches 91.3% in the whole visible and near-infrared range (0.38–1.50 μm). The total solar absorption in these energy regions is also up to 92.1%. Moreover, the high spectral absorption is insensitive to the incident angle. Interestingly, the absorption is observed to be with high tolerance for the polarized light even if the grating structure is used in the platform. These features suggest that the broadband solar absorption can be maintained well under complex electromagnetic surroundings. Otherwise, the absorbed energy is mainly confined at the proximity surface area of the Ti cavity, which suggests the strong plasmonic near-field localization and paves the feasible way to carry out the local heating operation for thermal antibacterial/antivirus applications. [ABSTRACT FROM AUTHOR]