Near-Infrared Down-Conversion and Energy Transfer Mechanism of Ce3+-Yb3+ Co-Doped Ba2Y(BO3)2Cl Phosphors

Abstract

Ce3+ and Yb3+ co-doped Ba2Y(BO3)2Cl phosphors are synthesized via a conventional high-temperature solid-state method in CO atmosphere. The structure and luminescent properties of sample are characterized by X-ray diffraction (XRD) and photoluminescence excitation (PLE) and emission (PL) spectra. The phosphor has strong broad band absorption and strong near infrared (NIR) emission, which matches well with the Si-based solar response curve. As a function of Yb3+ concentration, the decay time curves of Ce3+ emission in Ba2Y(BO3)2Cl: Ce3+, Yb3+ are measured to prove the occurrence of energy transfer (ET) from Ce3+ to Yb3+ and the energy transfer efficiency is also calculated. The energy transfer processes are also discussed, and possible transfer models are proposed. Results demonstrate that Ba2Y(BO3)2Cl: Ce3+, Yb3+ phosphors might act as a promising down-conversion (DC) solar spectral convertor to enhance the efficiency of the silicon solar cell by utilizing the broadband absorption for solar spectrum.