Interface models for the photochromism and thermochromism of glasses with nanocrystals
Interface models for the photochromism and thermochromism of glasses with nanocrystals
复制标题
纳米晶体玻璃的光致变色和热致变色界面模型
DOI：
10.1016/s0022-3093(02)01426-6
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发表时间：
2003
影响因子：
3.5
通讯作者：
V. F. Solinov
中科院分区：
文献类型：
--
作者：
S. L. Kraevskii;V. F. Solinov
研究了含AgCl2或CuCl2纳米晶玻璃的(UV，X-射线)/温度诱导吸收光谱。提出了这些玻璃的光色效应和热色效应的新模型。光致变色CuCL玻璃辐照后的漂白与烧毁光谱孔深度的减小同步进行。玻璃/纳米晶界面载流子注入陷阱的库仑场引起的CuCL纳米晶激子解离可以解释这种光谱烧孔现象。光致变色诱导光谱与著名的硅酸盐玻璃辐射色心谱带表现出很好的拟合。估计了界面处的陷阱参数。在热致变色光谱的情况下，在高于纳米晶体熔化温度的温度下，双带吸收光谱转变为单一的窄带被认为是Mie理论应用的唯一论点。根据一个新的模型对数据进行了解释，该模型涉及在含有纳米晶体或其熔体的空腔的内表面将扁球形金属银颗粒可逆地转变为连续的银涂层。
A study was made of the (UV, X-ray)/temperature induced absorption spectra of glasses with AgCl or CuCl nanocrystals. New models are proposed for photochromic and thermochromic effects in these glasses. Bleaching of the photochromic CuCl-glass after irradiation goes synchronously with diminishing of the burned out spectral hole’s depth. The CuCl nanocrystal exciton dissociation due to the Coulomb field of carriers injected into traps at the glass/nanocrystal interface can account for this spectral hole burning. The photochromic induced spectra display excellent fit with the bands of well-known silicate glass radiation color centers. Trap parameters at the interface are estimated. In case of the thermochromic spectra, the transformation at temperatures above nanocrystal melting temperatures of a two-band absorption spectrum into a single narrow band is considered a unique argument for Mie Theory application. The data are interpreted in terms of a new model that involves reversible transformation of oblate spheroid silver metal particles to continuous silver coating at the inside surface of a cavity containing a nanocrystal or its melt.