Luminescent properties and energy transfer of novel NIR K(Ga/ Al)11O17:Cr3+,Yb3+ phosphors for solar cells

Novel Cr3+-Yb3+ codoped KGa11O17 and KAl11O17 phosphors (referred to as KGO:Cr3+,Yb3+ and KAO:Cr3+,Yb3+) were prepared via a traditional solid-state method. X-ray diffraction, scanning electron microscope equipped with an energy-dispersive spectrometer, and photoluminescence spectra were used to characterize the phase purity, chemical composition, and luminescence properties of the phosphors. The obtained KGO:Cr3+ and KAO:Cr(3+)phosphors have high efficiency and broad absorption in the ultraviolet and visible (UVevis) region. Under 300/420 nm excitation, KGO:Cr3+ and KAO:Cr(3+)phosphors show deep red emission at about 712 nm. When Cr(3+)Yb(3+)are codoped into the KGO:Cr3+/ KAO:Cr(3+)matrix, the effective energy transfer from the Cr3+ -> to Yb3+ ions occurs, thus achieving intense near-infrared (NIR) emission. As a consequence, the high-energy UVevis light can be efficiently converted into low-energy NIR light in KGO:Cr3+,Yb(3+/)KAO:Cr3+,Yb3+ phosphors based on the energy transfer process of the Cr3+ /Yb3+ ions, which matches well with the high spectral response region of crystalline silicon (c-Si) solar cells. The experimental results reveal that KGO:Cr3+,Yb3+ and KAO:Cr3+,Yb(3+)phosphors are promising solar spectral conversion materials for c-Si solar cells. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Novel Cr3+-Yb3+ codoped KGa11O17 and KAl11O17 phosphors were prepared via a traditional solid-state method, showing high efficiency and broad absorption in the UVevis region. Energy transfer enables effective conversion of high-energy UVevis light into low-energy NIR light, making them promising solar spectral conversion materials for c-Si solar cells.