Electrochemical impedance studies of ethanol oxidation on synthesized poly methylene blue - poly pyrole films doped with nickel nano-particles

In this research, poly methylene blue and poly pyrole films were synthesized on the surface of platinum electrode by electrochemical method of cyclic voltammetry and their optimumconditions of synthesis are obtained. For investigation of the stability of poly methylene bluepoly pyrole composite, each freshly synthesized polymer separately undergoes 70 cycles in cyclic voltammetry. According to low decrease in anodic current peak, it was obvious that resultantpolymers are stable. Poly methylene blue and poly pyrole films do not have electrocatalytic property for ethanol oxidation. So, poly methylene blue-poly pyrole- nickel nanocamposite was synthesized and optimum conditions were established for nickel particles dispersion in polymermatrix by changing time and current parameters (current of -10 mA, during 50 s) in chronopotentiometry method. Scanning electron micrograph image of poly methylene blue-poly pyrolenickel nano-composite showed that spherical nickel particles of 97-135 nm was dispersed onmicro size poly pyrole. Electrocatalytic properties of nano-composite for ethanol oxidation were investigated in alkaline solution by electrochemical methods of cyclic voltammetry andimpedance. It was found that poly methylene blue-poly pyrole- nickel nano-composite has higher electrocatalytic property than poly methylene blue and poly pyrole individually and also each homo-polymers contained nickel particles. The charge transfer resistance of ethanol electrooxidation was reduced by increasing its concentration.

کلیدواژه ها:

Ethanol electro-oxidation ، Poly methylene blue ، Poly pyrole ، Nickel nano-particles