Microwave‐Facilitated Sensitization Route Boosting Efficiency, Thermostability, and Multifunction of Nanophosphors

Rare earth‐activated nanophosphors (NPs) have attracted significant attention due to their promising applications in compact and portable optoelectronic devices. However, limited by inherent nanoscale effects, achieving stable and efficient luminescence remains a long‐standing challenge. Herein, we developed microwave‐facilitated Ce sensitization engineering to obtain desirable green‐emitting NaSrY(PO 4 ) 2 (NSYP):Tb NPs. Compared to NSYP:Tb, benefiting from highly efficient Ce–Tb energy transfer, NSYP:Ce,Tb exhibits a 45.8‐fold enhancement in green emission intensity, along with exceptional internal quantum efficiency (IQE) of 82.2% and outstanding thermostability (93% intensity retention at 423 K). For health lighting, the NSYP:Ce,Tb NPs enable a high‐quality white lighting source with remarkable color rendering index of 94. For multimodal non‐contact thermometry, it can realize superior relative sensitivities across broad temperature ranges (2.28% K −1 at 473 K and 2.20% K −1 at 298 K). For X‐ray imaging, it reaches a spatial resolution of up to 18.1 lp/mm, which surpasses commercially mainstream scintillators by above 70%. This study provides a microwave‐facilitated sensitization route for multifunctional nanomaterials with high performance.