Cs_(2)NaBiCl_(6):Mn^(2+)一种橙黄色全无机双钙钛矿荧光粉

Cs_(2)NaBiCl_(6):Mn^(2+)-An Orange-yellow Inorganic Double Perovskite Phosphor

采用液相合成法制备Cs_(2)NaBiCl_(6):Mn^(2+)荧光粉,通过利用X射线衍射、荧光光谱对其结构及发光性能进行了研究.结果表明:随着Mn^(2+)的逐步引入,基质Cs_(2)NaBiCl_(6)中以Bi^(3+)为中心的局域激发强烈吸收近紫外光,Bi^(3+)向Mn^(2+)发生能量转移促进了原子d轨道之间的电子跃迁并导致了强烈的橙黄色光致发光.当锰铋摩尔比n(Mn)/n(Bi)达到0.7以后,由于浓度猝灭效应导致光致发光明显变弱,同时在发射谱中可以看到,在590 nm附近有1个宽的发射峰,为八面配位Mn^(2+)的^(4)T_(1)→^(6)A_(1)跃迁.激发谱包含了由Bi^(3+)的6s^(2)→6s^(1)6p^(1)激发产生的356 nm的吸收峰.Cs_(2)NaBiCl_(6):Mn^(2+)不含有毒元素,合成原料价格低廉,是一种具有潜在应用前景的新型橙黄色荧光材料.

A series of Cs_(2)NaBiCl_(6):Mn^(2+)double perovskite phosphors were prepared via liquid-phase synthesis,and their structures and luminescent properties were investigated by X-ray diffraction and fluorescence spectroscopy.The result show that with the gradual introduction of Mn^(2+),localized excitations centered on Bi^(3+) ions in the host lattice Cs_(2)NaBiCl_(6)strongly absorb near-UV light,and the energy transfer between Bi^(3+)and Mn^(2+)promotes the electron transition between atomic d orbitals,thus leading to an intense orange-yellow photoluminescence.The photoluminescence reduces when the manganese-bismuth molar ratio is 0.7 due to the concentration quenching effect.Also,a broad emission peak centered at 590nm is assigned to the^(4)T_(1)→^(6)A_(1)transition of octahedrally coordinated Mn^(2+).Based on the excitation spectrum,there are some peaks at 354nm that arise from 6s^(2)→6s^(1)6p^(1)excitations of Bi^(3+)ions.It is indicated that Cs_(2)NaBiCl_(6):Mn^(2+)could be a promising fluorescent phosphor synthesized without the use of expensive reagents and toxic elements materials.