National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland.
Phys Chem Chem Phys. 2011 Apr 21;13(15):7095-101. doi: 10.1039/c0cp02638g. Epub 2011 Mar 14.
Emission spectroscopy and electrochemistry has been used to probe the electronic communication between adjacent metal centres and the conjugated backbone within a family of imidazole based metallopolymers, Ru(bpy)(2)(PPyBBIM)(n), in the ground and excited states, bpy is 2,2'-bipyridyl, PPyBBIM is poly[2-(2-pyridyl)-bibenzimidazole] and n = 3, 10 or 20. Electronic communication in the excited state is not efficient and upon optical excitation dual emission is observed, i.e., both the polymer backbone and the metal centres emit. Coupling the ruthenium moiety to the imidazole backbone results in a red shift of approximately 50 nm in the emission spectrum. Luminescent lifetimes of up to 120 ns were also recorded. Cyclic voltammetry was also utilized to illustrate the distance dependence of the electron hopping rates between adjacent metal centres with ground state communication reduced by up to an order of magnitude compared to previously reported results when the metal to backbone ratio was not altered. D(CT) and D(e) values of up to 3.96 × 10(-10) and 5.32 × 10(-10) cm(2) S(-1) were observed with corresponding conductivity values of up to 2.34 × 10(-8) S cm(-1).
发射光谱和电化学已被用于探测一系列基于咪唑的金属聚合物Ru(bpy)(2)(PPyBBIM)(n)中相邻金属中心和共轭主链之间的电子通讯，其中 bpy 是 2,2'-联吡啶，PPyBBIM 是聚[2-(2-吡啶基)-双苯并咪唑]，n = 3、10 或 20。激发态下的电子通讯效率不高，在光学激发下观察到双发射，即聚合物主链和金属中心都发射。将钌部分偶联到咪唑主链上，导致发射光谱红移约 50nm。还记录了长达 120ns 的荧光寿命。循环伏安法也被用来说明相邻金属中心之间电子跳跃速率的距离依赖性，与之前报道的结果相比，当金属与主链的比例不变时，基态通讯减少了一个数量级。观察到高达 3.96×10(-10)和 5.32×10(-10)cm(2)S(-1)的 D(CT)和 D(e)值，相应的电导率高达 2.34×10(-8)Scm(-1)。
