NaBiNb_(2)O_(7)基光致变色材料的可逆荧光调控和温度传感特性

Reversible Fluorescence Regulation and Temperature Sensing Properties of NaBiNb_(2)O_(7)-Based Photochromic Materials

近年来,设计和发展新型光敏感的多功能材料已经成为研究热点,而稀土掺杂发光材料因其独特的光学性能备受关注。采用高温固相反应法合成了NaBiNb_(2)O_(7):0.01Er^(3+)/xYb^(3+)光致变色材料,在405 nm辐照下样品从淡绿色变成灰色,热刺激后可逆恢复到初始状态,表现出典型的光致变色效应;此外,材料在980 nm光激发下呈现出Er^(3+)离子的绿色(526和557 nm)和红色(667 nm)上转换发光。光致变色前后,上转换发光的调控比率(△I_(t))达到58.2%。基于荧光强度比技术,采用Er^(3+)离子的热耦合能级(^(2)H_(11∕2)和^(4)S_(3∕2))探究了样品在298~718 K范围内的光学温度传感性能,最高相对灵敏度达到1.18%K^(-1),这些结果对设计多功能光学温度传感性能具有指导作用。

In recent years,the design and development of light sensitive multifunctional materials have become a research hotspot.Rare earth-doped luminescent materials have attracted much attention due to their unique optical properties.In this paper,NaBiNb_(2)O_(7):0.01Er^(3+)/xYb^(3+)photochromic materials were synthesized by high-temperature solid-state reaction method.Under 405 nm irradiation,the samples change their color from light green to gray,and after thermal stimulation,the colored samples reversibly return to its initial state,exhibiting a typical photochromic effect.In addition,the materials exhibit green(526 and 557 nm)and red(667 nm)upconversion luminescence under 980 nm excitation.Before and after 405 nm irradiation,the luminescence modulation contrast(△I_(t))of upconversion luminescence is about 58.2%.Based on the luminescent intensity ratio(FIR)technique,the optical temperature sensing performance of the sample was studied in the temperature range from 298to 708 K using the thermally coupled energy levels(^(2)H_(11/2)and^(4)S_(3/2))of Er^(3+)ions,the optimized relative sensitivity(Sr)reaches up to 1.18%·K^(-1).These results provide a good method for designing multifunctional optical temperature sensing performance.