Investigation of upconversion and photoacoustic properties of NIR activated Er3+/Yb3+ doped [RE]VO4 (RE = Y, Gd) phosphors for photothermal conversion applications

Abstract

Er³⁺/Yb³⁺ doped YVO₄ and GdVO₄ phosphors were prepared through the combustion technique and were characterized through various techniques. XRD has revealed a tetragonal structure for YVO₄ and GdVO₄ phosphors. The 980 nm excited upconversion emission has resulted in intense green upconversion emission from both samples. However, the GdVO₄ sample has shown higher emission intensity. Photoacoustic heat generation in samples has been studied using the same 980 nm excitation, and in this case, the YVO₄ phosphor has shown higher heat generation. The YVO₄ phosphor again has shown lower heat dissipation and, hence, higher photo-thermal conversion efficiency upon irradiation of the sample.