Multi-responsive deep-ultraviolet emission in praseodymium-doped phosphors for microbial sterilization

镨掺杂的多响应型深紫外荧光粉与杀菌应用

Perusing multimode luminescent materials capable of being activated by diverse excitation sources and realizing multi-responsive emission in a single system remains a challenge.Herein,we utilize a heterovalent substituting strategy to realize multimode deep-ultraviolet(UV)emission in the defect-rich host Li_(2)CaGeO_(4)(LCGO).Specifically,the Pr^(3+)substitution in LCGO is beneficial to activating defect site reconstruction including the generation of cation defects and the decrease of oxygen vacancies.Regulation of different traps in LCGO:Pr^(3+)presents persistent luminescence and photo-stimulated luminescence in a synergetic fashion.Moreover,the up-conversion luminescence appears with the aid of the 4f discrete energy levels of Pr^(3+)ions,wherein incident visible light is partially converted into germicidal deep-UV radiation.The multi-responsive character enables LCGO:Pr^(3+)to response to convenient light sources including X-ray tube,standard UV lamps,blue and near-infrared lasers.Thus,a dual-mode optical conversion strategy for inactivating bacteria is fabricated,and this multi-responsive deep-UV emitter offers new insights into developing UV light sources for sterilization applications.Heterovalent substituting in trap-mediated host lattice also provides a methodological basis for the construction of multi-mode luminescent materials.

开发能够被不同激发光源激发,并在同一体系中实现多响应发射的多模态发光材料是发光材料领域的一个挑战.本文采用一种异价掺杂策略,在富含缺陷的Li_(2)CaGeO_(4)(LCGO)基质中实现了Pr^(3+)掺杂的多模式深紫外发射.LCGO:Pr^(3+)多响应特性使其能够被常见的光源,包括X射线管、标准紫外灯、蓝光和近红外激光器激发.Pr^(3+)掺杂产生并重建LCGO材料中的缺陷位点,包括阳离子缺陷的产生和氧空位的减少,进而调控了陷阱分布,使得该材料同时表现出余辉发光和光激励发光.基于Pr^(3+)离子的4f离散能级,该材料还表现出上转换发光,入射的可见光可转化为用于杀菌的深紫外发射.基于此,本文设计了一种双模光转换策略用于灭活细菌.这种多响应的深紫外发射体为开发用于杀菌的紫外光源提供了新的思路.在以陷阱为媒介的基质晶格中实施异价掺杂或者取代也为构建多模发光材料提供了可行途径.