Preparation Of Nanofibers Modified Electrode And Its Electrocatalytic Properties

In this paper, the indium tin oxide (ITO) electrode was modified with chitosan(CS) orcellulose acetate (CA) nanofibers by electrospinning method. After that, different substancessuch as Polyaniline (PANI), P2Mo18, and prussian blue were adsorbed on those eletrodes,respectively.1. We first made chitosan nanofibers modified electrode by electrospinning technique.PANI was electrodepositied on the modified ITO. The PANI/CS nanofibers modifiedelectrode shows excellent electrocalalytic ablitity towards nitrite. The sensitivity is 27.77μA/mM and the lowest detection limit is 0.45μM (S/N=3). Then we introduced poly(styrenesulfonate) (PSS) into polyaniline via electrochemical polymerization of aniline in thepresence of PSS on CS nanofibers modified electrode. The redox activity of the obtainedPSS-PANI/CS nanofibers modified electrode can be shifted to neutral condition because ofthe assembling of PSS. Moreover, it also shows excellent electrocatalytic ablitity towards DA.The sensitivity is 81.48μA/mM and the lowest detection limit is 0.70μM (S/N=3), whichoffers great promise for biosensing.2. The ITO electrode modified by CS nanofibers were made by electrospinning.α-[P2Mo18O62]6- (P2Mo18) was immobilized on the CS nanofibers by electrostatic interaction. Inorder to prove the superiority of the electrode, we made P2Mo18/CS membrane modifiedelectrode also. We used amperometry to study electrocatlytic activity of P2Mo18/CSnanofibers and membrance modified electrode. The result shows that P2Mo18/CS nanofibersmodified electrode has higher electrocatalytic ablitity towards nitrite than P2Mo18/CSmembrance modified electrode. The sensitivity of P2Mo18/CS nanofibers modified electrode is73.18μA/mM and the lowest detection limit is 0.34μM (S/N=3).3. The CA nanofibers modified ITO electrode was made by electrospinning. In thepretection of PDDA, nano-sized prussian blue particles were synthesized with a chemicalmethod. The electrospun CA nanofibers are insoluble in water but carry numerous negativecharges which can provide a great driving force for the adsorption of oppositely chargedsubstance. The PDDA protected P-PB nanoparticles which carry positive charges wereimmobilized on the CA nanofibers by electrostatic interaction. The P-PB/CA nanofibersmodified ITO electrode shows excellent electrocatalytic ablitity towards H₂O₂. The sensitivityis 3.02μA/mM and the lowest detection limit is 2.41μM (S/N=3).