Up-conversion luminescence and temperature sensing properties of Ho3+ activated Na3Y(VO4)2 phosphors under 980 and 808 nm excitation

A series of Yb3+, Ho3+, Nd3+ doped Na3Y(VO4)2 phosphors are prepared by the high temperature solid reaction method. Na3Y(VO4)2: Yb3+, Ho3+ present bright yellow emission under the excitation of 980 nm. The introduction of Nd3+ can effectively absorb 808 nm photon energy, realizing the energy transfer process of Nd3+ (sensitizer)→Yb3+ (energy transfer bridge)→Ho3+ (activator) under 808 nm excitation. Up-conversion mechanism proves that the variable luminescence color at different concentrations Nd3+ doped samples may be attributed to back energy transfer between Ho3+ and Nd3+. Moreover, the temperature sensing behaviors are investigated by the fluorescence intensity ratio technology. The maximum temperature sensing sensitivities can be maintained as a constant of 10 × 10−3 K over the whole temperature measurement range (298–618 K), which is beneficial to achieve stable optical thermometry. The phosphors can achieve color tunable luminescence within green and yellow region by adjusting the temperature. Ho3+ activated Na3Y(VO4)2 phosphors with excellent sensitivity performance have excellent prospects in the fields of optical anti-counterfeiting and temperature sensing.