Measurement of interchain and intrachain exciton hopping barriers in luminescent polymer.
Measurement of interchain and intrachain exciton hopping barriers in luminescent polymer.
复制标题
发光聚合物中链间和链内激子跳跃势垒的测量。
DOI：
10.1088/0953-8984/24/1/015801
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Santos PL
中科院分区：
文献类型：
--
作者：
Santos PL
用类Mott温度特性分析了“超级黄”共聚物薄膜的积分光致发光强度。这使得我们能够观察到来自两个发射通道的贡献，表明激子复合来自两个不同的来源。在高温下，链间热激活激子的能量传递和迁移占主导地位，导致积分发射强度和光致发光量子产率的大规模猝灭。然而，在相对较低的温度下，会出现积分发射强度的额外增加。这一新的发射通道被归因于激子的复合，其中链内激子的能量在共聚主链的相邻亚单位之间的转移受到阻碍。得到了控制这两个发射通道的激活能垒，并与链主链自由度相关联。
The integrated photoluminescence intensity in thin films of'Super Yellow'copolymer has been analyzed using a Mott-like temperature dependence. This has enabled us to observe contributions from two emission channels, indicative of exciton recombination proceeding from two distinct origins. At high temperature, interchain thermally activated exciton energy transfer and migration dominates, resulting in large scale quenching of the integrated emission intensity and hence the photoluminescence quantum yield. However, at relatively low temperature, an additional increase of the integrated emission intensity occurs. This new channel of emission has been attributed to recombination from excitons where intrachain exciton energy transfer between adjacent subunits of the copolymer backbone becomes hindered. The activation energy barriers that control both of these emission channels have been obtained and are correlated with chain backbone degrees of freedom.