有机-无机杂化金属卤化物作为一种高性能白光发光二极管的荧光粉材料已被广泛研究。在本文中,通过机械化学方法合成了一系列具有不同Mn2离子掺杂浓度的有机-无机金属卤化物(C3H10N)4Pb1-xMnxBr6粉末,在室温下发出宽带白光,光致发光量子产率为36.1%,在80K时变绿强度更大。有趣的是,在100°C处理后,其发射从白色转化为红色,并在暴露于潮湿空气一段时间后再次变成白色。这种发射变化是由通过电介质限制在产品粉末表面上的吸附水层引起的。没有水粉的红色发射被确定为发生在点共享八面体位置的Mn铁磁对中,而宽带白色发射源于地表水辅助的介电限制和表面极化,它们结合了产物中Mn离子和Mn对的自陷激子和d-d跃迁。此外,这种白色发射可以在80K下以更强的强度转变为绿色,由吸附的冻结水层产生的均匀有效的表面介电限制。这种特殊的化合物具有制备简单的优点,低成本,稳定性好,甚至在空气中含有水分子,发出近乎完美的白色发射,CIE为(0.33,0.35),相关色温约为5733K,可用于不同的应用,如传感,固态照明,和显示。
Organic-inorganic hybrid metal halides have been widely studied as a kind of phosphor materials for high-performance white light-emitting diodes. In this paper, a series of organic-inorganic metal-halide (C3H10N)4Pb1-xMnxBr6 powders with different Mn2+ ion doping concentrations were synthesized by mechanochemical methods, giving broadband white light emission with a photoluminescence quantum yield of 36.1% at room temperature, which turn green with a much larger intensity at 80 K. Interestingly, its emission converted from white to red after 100 °C treatments and turned back to white again when exposed to moist air for a while. This emission variation was caused by the adsorbed water layer on the surface of product powders via the dielectric confinement. The red emission from no water powders is identified to occur from the Mn ferromagnetic pair in point-shared octahedral sites, while the broadband white emission originated from the surface water-assisted dielectric confinement and surface polarization which combine the self-trapped excitons and d-d transitions of Mn ions and Mn pairs in the product. Moreover, this white emission can transform into green color at 80 K with a much stronger intensity, caused by the even efficient surface dielectric confinement by the adsorbed frozen water layer. This special compound has the advantages of simple preparation, low cost, and good stability and even contains water molecule in the air, giving a near-perfect white emission, with CIE of (0.33, 0.35) and correlated color temperatures at around 5733 K, which may be used for different applications such as sensing, solid-state lighting, and display.