Integration of high-thermal-responsive color change and invisible emission intensity ratio in Gd2Mo4O15 lattice with the desired structure

Thermal-responsive upconversion luminescence (UCL) is of interest due to its potential application in anti-counterfeiting and temperature sensing. However, integrating the multi-model emission intensity ratios with high-thermal sensitivity, especially those involving invisible UCL, into a single host lattice remains challenging. In this work, the color change of blue to bluish-purple and invisible emission intensity ratio with a temperature sensitivity as high as 13.47% K−1, thanks to the crossover-reduced thermal quenching and the Yb3+-MoO42- dimer sensitization, are available in the monoclinic Gd2Mo4O15:Yb3+/Tm3+. Moreover, the temperature-dependent color response is tunable, such as the introduction of Er3+ results in a color change from blue to bluish-green. Our results allow promising temperature-dependent UCL applications and open the opportunity for other functional materials based on Re2Mo4O15 with desirable phase structures.