Near-infrared downshifting luminescence of Ca2LaTaO6:Nd3+/Yb3+/K+ phosphors and their applications: solar cells and anti-counterfeiting

A series of Nd3+/Yb3+ co-doped Ca2LaTaO6 (CLTO) phosphors are synthesized by a high temperature solid phase method. Structural characterization confirms the successful incorporation of Nd3+ and Yb3+ ions into the CLTO host lattice. The photoluminescence excitation (PLE) spectra and photoluminescence (PL) spectra of CLTO:Nd3+ and CLTO:Nd3+/Yb3+ are investigated in detail. Under the excitation of ultraviolet (UV) and visible (VIS) light, the CLTO:Nd3+/Yb3+ phosphor emits broadband near infrared (NIR) luminescence. In particular, the luminescence intensity of the Yb3+ ion is increased through an energy transfer (ET) process from Nd3+ to Yb3+. The luminescence mechanism of the CLTO:Nd3+/Yb3+ sample is analyzed based on the decay lifetime and PL spectra. In addition, the NIR emission intensity of Yb3+ ions is also enhanced by doping K+ ions. The broadband luminescence (850-1050 nm) of the CLTO:Nd3+/Yb3+/K+ phosphor has good application in solar cells and anti-counterfeiting.A series of Nd3+/Yb3+ co-doped Ca2LaTaO6 (CLTO) phosphors are synthesized by a high temperature solid phase method. Structural characterization confirms the successful incorporation of Nd3+ and Yb3+ ions into the CLTO host lattice. The photoluminescence excitation (PLE) spectra and photoluminescence (PL) spectra of CLTO:Nd3+ and CLTO:Nd3+/Yb3+ are investigated in detail. Under the excitation of ultraviolet (UV) and visible (VIS) light, the CLTO:Nd3+/Yb3+ phosphor emits broadband near infrared (NIR) luminescence. In particular, the luminescence intensity of the Yb3+ ion is increased through an energy transfer (ET) process from Nd3+ to Yb3+. The luminescence mechanism of the CLTO:Nd3+/Yb3+ sample is analyzed based on the decay lifetime and PL spectra. In addition, the NIR emission intensity of Yb3+ ions is also enhanced by doping K+ ions. The broadband luminescence (850-1050 nm) of the CLTO:Nd3+/Yb3+/K+ phosphor has good application in solar cells and anti-counterfeiting.