Cr3+/Yb3+/Nd3+-doped Ba2LaGa11O20 broadband NIR phosphors for NIR pc-LED and c-Si solar cells

Broadband near-infrared (NIR) phosphors are urgently demanded for smart phosphor-converted light-emitting diodes (pc-LEDs). Herein, a new broadband NIR phosphor Ba2LaGa11O20:Cr3+ (Abbreviated as BLGO:Cr3+) was successfully synthesized for the first time and its luminescent properties were systematically studied. The excitation of BLGO:Cr3+ covers the ultraviolet and visible regions with a maximum of 468 nm, which is well matched with the low-cost commercially available blue LED chip. Under 468 nm blue light excitation, a broad NIR emission band with a peak at 738 nm and a full-width at half maximum (FWHM) of 133 nm was detected in the emission spectrum of BLGO:Cr3+. In addition, using Cr3+ as sensitizer, the Cr3+ → Yb3+/Nd3+ energy transfer is realized in BLGO matrix, so that BLGO:Cr3+,Yb3+/Nd3+ phosphors can absorb ultraviolet and visible light and emit NIR light matching with the optimal absorption of c-Si solar cells. Effective spectral conversion is achieved in BLGO:Cr3+,Yb3+/Nd3+ phosphors. The results indicate that BLGO:Cr3+ and BLGO:Cr3+,Yb3+/Nd3+ are potential broadband NIR phosphors for NIR pc-LED and spectral conversion materials for c-Si solar cells.