Low-temperature wet chemical precipitation of YVO₄:Bi ³⁺,Eu³⁺ nanophosphors via citrate precursors

YVO₄:Bi³⁺,Eu³⁺ nanophosphors are prepared by low-temperature wet chemical precipitations in the presence of citrate ions. Transparently dispersed YVO₄:Bi³⁺,Eu³⁺ nanophosphors crystallize from amorphous gel precursors through a gel-sol process. The homogeneity of Bi³⁺ doping process as well as the photoluminescence property are improved by using the homogeneous Bi³⁺ solution as a Bi³⁺ source instead of Bi³⁺ powder. YVO₄:Bi³⁺,Eu³⁺ nanophosphor under the irradiation of near-UV light shows peculiar photobleaching behavior through the reduction from V⁵⁺ to V⁴⁺, but this photobleach is suppressed by subsequent hydrothermal treatment. The authors also discuss the advantage of transparency of YVO₄:Bi³⁺,Eu³⁺ nanophosphor in terms of wavelength conversion as compared to micron-sized phosphor.