Near-infrared Quantum Cutting in Eu3+-Yb3+ co-doped YAG through Downconversion for Silicon Solar Cell

Near-infrared (NIR) quantum cutting (QC) could provide a solution to minimise the heat loss due to the thermalisation of electron-hole pairs in solar cells by converting high-energy photons to low-energy photons matching with the greatest spectral response of silicon solar cell. Europium (Eu3+) and ytterbium (Yb3+) co-doped yttrium aluminium garnet (Y3Al5O12, YAG) can be used as QC phosphor with emission in both visible and NIR regions. In this study, upon the excitation at 394 nm, the 5D0→ 4f 6 transition of Eu3+ is induced, the characteristic NIR emission located at 1030 nm due to the energy transfer between of 2F5/2-2F7/2 levels of Yb3+, is generated. The quantum efficiency (QE) was derived to be as high as 144%. The results showed the possibility for enhancing the photovoltaic conversion efficiency of silicon-based solar cell by modifying the absorption and utilising the energy in the UV-blue part of the solar spectrum.