Self-Assembly of Broadband White-Light Emitters

We
use organic cations to template the solution-state assembly
of corrugated lead halide layers in bulk crystalline materials. These
layered hybrids emit radiation across the entire visible spectrum
upon ultraviolet excitation. They are promising as single-source white-light
phosphors for use with ultraviolet light-emitting diodes in solid-state
lighting devices. The broadband emission provides high color rendition
and the chromaticity coordinates of the emission can be tuned through
halide substitution. We have isolated materials that emit the “warm”
white light sought for many indoor lighting applications as well as
“cold” white light that approximates the visible region
of the solar spectrum. Material syntheses are inexpensive and scalable
and binding agents are not required for film deposition, eliminating
problems of binder photodegradation. These well-defined and tunable
structures provide a flexible platform for studying the rare phenomenon
of intrinsic broadband emission from bulk materials.

本研究采用有机阳离子作为模板，以构建大块晶体材料中波纹状卤化铅层的溶液状态组装。此类层状杂化材料在紫外光激发下可辐射出整个可见光光谱。它们作为单源白光发光材料，与紫外光发射二极管配合应用于固态照明设备中具有广阔的应用前景。其宽带辐射特性提供了高色彩还原性，且通过卤素取代可调节发射的色度坐标。我们已成功分离出能够发出所需“暖白光”的室内照明应用材料，以及近似太阳光谱可见区域的“冷白光”材料。材料合成过程经济且可扩展，且无需使用粘合剂进行薄膜沉积，从而避免了粘合剂光降解问题。这些结构明确且可调的体系为研究大块材料中固有的宽带辐射这一罕见现象提供了灵活的平台。