Highly Sensitive Dual-Phase Nanoglass-Ceramics Self-Calibrated Optical Thermometer

A strategy to achieve high sensitivity of noncontact optical thermometer via the structure design of nanoglass-ceramic and the usage of Ln3+ (Ln = Eu, Tb, Dy) luminescence as reference signal and Cr3+ emission as temperature signal was provided. Specifically, the synthesized dual-phase glass-ceramics were evidenced to enable spatially confined doping of Ln3+ in the hexagonal GdF3 nanocrystals and Cr3+ in the cubic Ga2O3 nanoparticles, being beneficial to suppressing detrimental energy transfer between Ln3+ and Cr3+ and thus significantly enhancing their luminescence. As a consequence, completely different temperature-sensitive luminescence of Ln3+4f → 4f transition and Cr3+ 3d → 3d transition in the present glass-ceramic resulted in obvious variation of Cr3+/Ln3+ fluorescence intensity ratio with temperature and strikingly high detecting temperature sensitivity of 15–22% per K. We believe that this preliminary study will provide an important advance in exploring other innovative optical thermometry.