Compound nanostructure capable of realizing full-spectrum utilization of solar energy for PV-TE hybrid systems.

Abstract

The photovoltaic-thermoelectric (PV-TE) hybrid system can achieve full-spectrum utilization of the solar spectrum, but surface reflection has always been an important reason to suppress its power conversion efficiency. Therefore, a novel composite nanostructure (CN) is proposed by the finite-difference time-domain (FDTD) simulation method to reduce the surface reflection in the spectral range of 0.3-2.5μm, which consists of a pyramid and grating structure. For the sake of generality, this paper studies the spectral reflectance of the CN under multiple parameters. The results show that the CN integrated pyramid and grating correspond to excellent anti-reflection performance in the short wavelength range and long wavelength range, respectively, compared to a unitary structure, achieving anti-reflection in the full spectral range. In addition, the CN expresses the insensitivity to the structural parameters, and has lower reflectivity compared with a commercial battery. The mechanism for achieving this full-spectrum anti-reflection is mainly to enhance the path of light in the medium to enhance absorption and achieve high transmission under the action of the waveguide. This paper implements ultra-broadband anti-reflection of a compound nanostructure for full-spectrum utilization of solar energy, and provides a solution to improve the power conversion efficiency of PV-TE hybrid systems.