TCNQ和TMB电荷转移配合物自组装膜的制备及光谱研究

本文利用layer-by-layer技术制备了以TMB为电子给体以TCNQ为电子受体的电荷转移配合物自组装膜。在自组装膜的付立叶-红外透射光谱中TCNQ组分的C≡N的伸缩振动峰出现在2205cm-1,与游离的中性TCNQ中的C≡N峰位置明显不同。这不仅证明TCNQ和TMB确实形成了电荷转移配合物,而且可以据此计算出电荷转移配合物的电荷转移度为0.42。自组装膜的紫外-可见-近红外光谱中,出现一个非常宽的吸收带,中心位置在2030nm处,说明形成的电荷转移配合物是混合堆积排列。从原子力显微镜照片可以看出,电荷转移配合物自组装膜的表面形貌是由颗粒组成的,这些颗粒的尺寸约为80nm。

Preparation and Spectroscopic Study of the Self-assembled Monolayer of TCNQ and TMB

A monolayer of the charge transfer(CT)complex of TMB and TCNQ has been prepared by the layer-by-layer self-assembled method.Structure and morphology of the complex of the films have been investigated by FT-infrared(IR),ultraviolet-visible-near-infrared(UV-VIS-NIR) spectroscopies and AFM.In the UV-VIS-NIR absorption spectrum,the appearance of a very broad absorption band centered at about 2030 nm in the near-infrared region shows that the mixed-stack CT complex of TMB·TCNQ is formed.In the transmission FT-IR spectrum,the C≡N stretching band in the CT films is observed at 2205 cm~(-1).By the frequency shift of C≡N stretching band,we can estimate that the degree of charge transfer is to be 0.42.The AFM picture of the complex film of TMB and TCNQ shows that its morphology consists of many particles pied up on the plate surface and the sizes of these particles is about 80nm.