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稀土离子掺杂铁电陶瓷是一类新型光致变色材料,在光开关、光信息存储等领域具有潜在应用价值.本研究采用水热法制备了(K0.5Na0.5)1-xEuxNbO3(KNN∶xEu)前驱体粉体,随后利用高温烧结得到对应陶瓷样品.在465 nm激发下,观察到615 nm处有强的红色发光,对应于Eu3+的5D0→7F2跃迁.通过紫外光照射,KNN∶Eu陶瓷从乳白色变为深灰色.随后经过200℃加热10 min,着色陶瓷又变回到初始颜色,显示出良好的光致变色行为.紫外照射和反复加热循环可以有效调控该陶瓷的发光强度.且经过多次循环之后,发光强度没有明显衰减.在紫外光照射下,KNN:0.06Eu陶瓷发光强度的可调比(△Rt)高达83.9％,说明发光具有良好的可调性.进而结合发光中心和色心之间的能量转移,对KNN∶Eu陶瓷的光致变色和发光机理进行了解释.“,”Rare-earth doped inorganic ferroelectrics are considered as novel photochromic materials,with potential applications for optical switch and information storage (K0.5Na0.5)1-xEuxNbO3 (KNN∶xEu) ceramics were prepared by high temperature calcination,with precursor powder obtained by hydrothermal method.Strong red emission at 615 nm was observed which corresponds to the 5D0→7F2 transition of Eu3+ under excitation of 465 nm.Under UV light irradiation for 3 min,the color of the ceramics turned from milky white to dark gray.The colored samples returned to the original color when heated at 200 ℃ for 10 min,showing strong photochromic behavior.Meanwhile,the luminescence intensity of Eu3+ can be tuned without obvious degradation by alternating UV light and heat stimulus.Upon UV light irradiation,large luminescence modulation ratio (ARt) up to 83.9％ was achieved for KNN:0.06Eu,indicating good luminescence switching behavior.A possible mechanism for non-radiative energy transfer from the luminescent center to the color center was proposed according to their luminescent behavior.