偶氮苯衍生物自组装膜的表征及组装动力学

The Adsorption Kinetics and Characterization of Azobenzene Self-Assembled Monolayers on Gold

报导了4-正辛基-4′-（3－巯基丙氧基）偶氮苯（简称C8AzoC3）自组装膜（Self-AssembledMonolnyersSAMs）的表征及其自组装成膜动力学，接触角滴定、原子力显微镜（AFM）及电化学的实验结果表明，C8AzoC3分子在金表面自组装形成致密有序的流水性单分子膜，并且在电极上没有明显的电化学响应．通过控制组装时间，考察了偶氮苯自组装形成单分子膜的动力学过程，从接触角和电化学数据得到组装过程的速率常数kad为（1.2±0.2）×103mol-1·dm3·s－1；依据不同组装时间形成的自组装膜的特征循环伏安行为，提出了C8AzoC3分子在金表面自组装过程的动态模型．

The characterization and adsorption kinetics of azobenzene self-assembled monolayers(C8AzoC3 SAMs) on gold were reported. By assembling for about 24 hours,highly ordered and closely packed C8AzoC3 SAMs can be formed on gold surface and showed no electrochemical response, which were evidenced by contast angle titration,atomic force microscopic abservation afld electrochemical measurements. The edsorption kinetics of C8AzoC3 molecules on gold was studied by controlling the assembling time and accompanying with dynamic characterization. The adsorption kinetic rate constant was estimated to be (1 .2±0.2) × 103 mol-1·dm3·s-1 by using the data of contast angle titration and electrochemical measurements. A simple model of the self assembling process was suggested to illustrate the unique electrochemical behavior of C8AzoC3 SAMs.