Temperature and concentration effects on upconversion photoluminescence properties of Ho3+ and Yb3+ codoped 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 multifunctional ceramics

Abstract

Ho3+ and Yb3+ codoped lead magnesium niobate–lead titanate (PMN–PT) ceramics with various doping concentration have been fabricated by conventional solid reaction method. Under the excitation of 980nm laser, as-synthesized samples exhibit bright yellow-green upconversion (UC) luminescence. Their UC photoluminescence properties were investigated by the emission spectra with respect to various concentration of Ho3+ and Yb3+. Results show that optimal luminescent concentration was obtained in 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 ceramics codoped with 0.5mol% Ho3+ and 2mol% Yb3+ (abbreviated as 67PMN–33PT:2Yb,0.5Ho). The possible mechanism of UC emission was discussed by energy level diagrams of Ho3+ and Yb3+ ions according to the dependence of integrated intensity of UC emission bands on pumping power. Furthermore, the temperature dependence of UC emission intensity of 67PMN–33PT:2Yb,0.5Ho sample was investigated in detail in the range of 25–180°C under excitation by a 980 diode laser. According to Arrhenius formula, the fitting result of the effect of temperature on integrated intensity of emission band was coinciding well with the experiment results. It is shown that the emission intensity depends strongly on temperature, which has excellent relative sensitivity with its maximum value of 0.77%K−1 at 93°C. These indicate that the 67PMN-33PT:2Yb,0.5Ho ceramic may be useful for temperature sensing and optical-electrical devices as a multifunctional material.