Doped Polypyrrole Electrochemical Synthesis And Research Of Its Electrochemical Properties

Conducting polypyrrole has been much attracted due to its flexible mechanical, processing,reversible chemical and electrochemical reduce properties. Though singe-polypyrrole is limited inapplication, doped-polypyrroles have semiconductive conductivity and electrical property and excellentstability. Hence, it is very important to explore suitable methods to improve their conductivity. Tomodify polypyrrole and polypyrrole electrodes, in this paper, we synthesized polypyrrole viaelectrochemical method. And, to obtain suitable reactive conditions to improve their electrical properties,we doped polypyrrole with electrochemical oxidation and reduction and protonic acid by controllingdifferent synthesized conditions. Additionally, we investigated polypyrrole doped by different sulfonate,the electric color effect of polypyrrole electrode doped by different dyes and their catalytic properties.1. The synthesis of polypyrrole and electrochemical properties.Polypyrrole were prepared on ITO bythe method of potentiostatic deposition. The morphology and electrical properties of the as-preparedpolypyrrole were studied by controlling the synthetic potential, reaction time, and the doped Inorganicanions. The result shows that the PPy film prepared at0.8V have better adhesion on ITO and,the reactiontime is for50s, the polypyrrole film is great smooth and, with time increasing, the wrinkle of the polypyrroleare more obvious. By CV and EIS, we can observed that C1ion exchange membrane is a low transmissionresistance, electrochemical exchange reaction is easy and it exhibits diffusion charge saturation process inthe low frequency part.2.Influence on the morphology and electrochemical properties by sulfonic acid group dopeding.Sulfonic acid group was doped in polypyrrole by potentiostatic method and investigated the influenceon morphology and electrochemical properties of polypyrrole. We can see in SEM image that the size of the as-prepared PPy particles doped by sulfonic acid are distributed from micrometer to nanometer and PPy filmwithout sulfonic acid group is more smooth than that of being doped. CV and EIS show that the oxidation ofsulfonic acid group entering polypyrrole film is irreversible. Steric hindrance of sulfonic acid group is larger.When it went into PPy film, it was firmed in PPy film. The process of doping and undopig is really theprocess of anion-cation ion with small volume going into and out PPy. The ion in solution easily entered inand exhausted the PPy, which can enhance cyclic stability of the membrane.3.The electric colour effect of polypyrrole in different dyes.The modified glass carbon electrodes wereprepared by depositing different dyes via potentiostatic method. The electric color effect of polypyrrole inKCl solution is studied by electrochemical method. The SEM image shows that the morphology of thepolypyrrole was changed. Methylene blue doped by microsphere, Rhodamine B doped by not uniformstructures and Malachite green doped by micro and nano-scale. We can observe that the doped PPy haveobviously color change in cyclic potentiodynamic scanning. CV and EIS show that the doped polypyrroleelectrodes have high cyclic life and good chemical stability.4.The electrocatalytic oxidation of polypyrrole for different alcohols.The modified glass carbonelectrodes were prepared by depositing different sulfonate via potentiostatic method. The electrocatalyticoxidation propertoes of the as-prepared electrodes are studied by electrochemical method. CV shows that theoxidation peak current, If/Ib rate and catalytic activity of the modified PPy/GCE electrodes increasedobviously in the process of catalytic alcohols. With concentration of alcohols increasing, the oxidation peakand catalytic activity decreased gradually. The modified electrodes have good response to the lowconcentration of alcohols.