Abstract

Abstract The mismatch between the absorption spectrum of silicon solar cells and the solar spectrum is the main factor limiting the photovoltaic conversion efficiency. In this work, broadband sensitized near-infrared (NIR) emission Ba 5 Si 2 O 6 Cl 6 :Eu 2+ ,Yb 3+ phosphors were prepared by the high-temperature solid-state method. This phosphor appears green emission in natural light and the particle size observed using a scanning electron microscope is approximately 2 microns. The broadband absorption property of Eu 2+ ions enables the materials to absorb photons in the ultraviolet-blue region of 210-500 nm and transfer the energy to Yb 3+ , causing Yb 3+ to emit NIR photons of 974 nm due to the Yb 3+ : 2 F 5/2 → 2 F 7/2 transition. The NIR spectra match the bandgap of silicon (1.12 eV), reducing energy loss due to thermal vibrations. The materials have excellent optical properties and can be applied as spectral modulators on the surface of silicon solar cells to solve the spectral mismatch problem, which has a promising application in silicon solar cells.