The Self-assembly Monolayers Of Heterocyclic Aromatic Selenium (Sulfur) Compounds With Plane-conjugated System

This thesis was mainly researched the self-assembly monolayers (SAMs) of Heterocyclic aromatic selenium or sulfur Compounds with plane-conjugated system on gold surface, their characteristic by the means of electrochenmistry and contact angle titration. The details are as follows:1, The SAMs of Heterocyclic aromatic sulfur Compounds on gold surface: the electrochemical behavior of the SAMs modified with heterocyclic aromatic sulfur compounds was investigated also with the formation of SAMs, electrode interfacial capacitance and their electron transfer mechanism. The results showed that this kind of compounds could form SAMs on gold surface, the thickness and density had concern with their molecular structure. Thereinto, the SAMs of TPT was most compact; the SAMs of TP improved the electron transfer effectively; The TCA monolayer's surface coverage approximately was 95 % and the SAMs of MT was not formed. The contact angle of this kind of compounds was between 60° and 80°.2, The formation kinetics and solvent effects of Selenium compound SAMs on Gold surface: Use Fe(CN)64-/3- as probe, through comparing the electrochemical behavior of NS self-assembled monolayer in different solvents on gold surface to study the solvent effects to the formation process of NS. Using electrode interface capacitance and surface coverage to investigate the formation kinetics of NS monolayer in hexahydrobenzene solvent. The results indicated that with the assembly times increasing, the surface coverage augmented and the interface capacitance reduced gradually. The monolayers prepared in different solvents showed electrocatalytic oxidation to Fe(CN)64-/3-, interface capacitance was effected by solvent and scan rate . With the increase of scan rate, the interface capacitance reduced gradually.3, The SAMs of Heterocyclic aromatic selenium Compounds on gold surface and their electrochemical characteristic: This paper obtained the self-assembly monolayers of Heterocyclic aromatic selenium Compounds such as SPb; SPO and SPDO on gold surface and studied ectrochemical behavior of the modifiedelectrode and their solutions by the means of cyclic voltammetry. The results showed that the electrode process in the solution was mainly controlled by adsorption; the electrochemical characteristic of SAMs were similar with the solution, namely there were reduction peak at -600mV, they had the similar assembly mode. Thereinto, the SAMs of SPO and SPDO on gold surface was densely and steadily formed and hold back the the electron transfer from solution to electrode surface.4 , Synthesis and characterization of Heterocyclic aromatic Selenium compounds: A series of heterocyclic aromatic selenium compounds of BS, SPb, MB, SPDO and NS were synthesized in liquid, solid state and under microwave radiation conditions with their respective ortho-aromatic diamines and selenium dioxide.The yields under microwave radiation conditions were between 29% and 84 %. The products obtained from the microwave solid-state reaction were characterized by IR, XRD, UV, FS, EA and compared with the products obtained from liquid-state reaction and the solid-state reaction. The results indicated that the reaction under the microwave radiation conditions was friendly to the environment, completed with higher yields, less time and more convenient sequential process.