Trivalent lanthanide doped orthovanadate phosphors for efficient upconversion

Abstract

Lanthanide doped crystalline materials has gathered an immense impression to develop highly efficient upconverting phosphors for industrial as well as biomedical applications. The interaction between the electron cloud of the lanthanides and the crystal field of different host matrices affects the transition probabilities between the energy levels of lanthanide ions. Here, we have investigated the structural and optical properties of Er3+ doped YVO4 phosphors with the irradiation of 980 nm continuous wave diode laser. A twin efficient green band peaking at ∼ 525 nm and ∼ 554 nm has been observed along with a relatively low intense red band at ∼ 660 nm. The radiative/non radiative transitions between energy levels of Er3+ ions are well understood with the help of energy level diagram. The pump photons required to populate the green and red levels have been calculated. The colour coordinate of the prepared phosphors has been calculated by CIE chromaticity diagram. The present lanthanide-based phosphors have an efficient and bright upconversion emission, with applications spanning optical sensing, biological imaging, solid state lighting and LEDs.