Enhanced spectral splitting in a novel solar spectrum optical splitter based on one dimensional photonic crystal heterostructure

Abstract Controlling the distribution of solar spectrum in different bands would boost the energy harvesting efficiency and optimize the energy dispatchability. 1D photonic crystal with intrinsic optical band gap can be used to split the solar spectrum for hybrid photovoltaic/thermal solar applications. Here, we designed an efficient solar spectrum optical filter based on a cermet layer, Si/SiO2 1D photonic crystal, and top heterostructure layer. Compared with 1D photonic crystal structure, the 1D photonic crystal heterostructure with top YSZ layer can realize the reflectance of greater than 92% in PV band and the low average reflectance in two thermal bands by tuning the effective impedance of multilayer films. The enhanced reflectance in PV band results from the huge mismatching of impedance between free space and the heterostructure structure. The top dielectric layer can also be extended to other oxides.