Influence of Lu3+on Power-responsive Upconversion Luminescence Chromaticity of Er2Mo4O15∶Tm3+
In the Er2Mo4O15∶Tm3+system reported in the previous paper,by introducing inert Gd3+and Lu3+to replace Er3+,the power-responsive color change has been improved by 31.5%.The study of the physical mechanism shows that when Lu3+is doped,the contraction of the lattice strengthens the Er3-Tm3+coupling,and the electrons at the 4I 11/2 energy level are more populated into the light-emitting level for red UCL in the form of Er3+→Tm3+→ Er3+,thus making the IR/IG larger at low power.On the other hand,thanks to the improved Er3+-Tm3+coupling,the coefficient of the power term is larger,followed by a better power response behavior.This study reports a new strategy for fine-tuning Er3+-Tm3+coupling and provides a reference for the regulation of power-responsive color regulation of UCL.