Synthesis Of The Polyaniline Composite Modified Neural Electrode And The Effect Of Substrate Roughness On Interface Properties Of These Modified Electrodes

In order to improve the electrochemical performance and stability of neural electrode,the sulfosalicylic acid?SSA?and multi-walled carbon nanotubes?MWCNTs?doped polyaniline?PANI?composite modified electrodes were synthesized by electro-polymerization.The PANI composite modified electrode has been characterized utilizing SEM,FTIR and electrochemical techniques.Platinum?Pt?substrates were electrochemically roughened and the morphology and conductivity of roughened Pt was characterized by AFM and electrochemical station.The roughened Pt electrodes modified with PANI coatings were evaluated for use as neural electrodes utilizing SEM and electrochemical techniques.The results showed that:the morphology of SSA/MWCNTs doped PANI composite modified electrode was more uniform and compact compared with PANI modified electrode.It was showed that the conductive properties improved significantly,the charge injection capacity of the electrode increased by about 12.1-fold.The surface roughness factors?f_R??up to 424?of Pt substrates can be increased in a controlled manner.With the increase of f_R,the roughened substrates showed increasing electrochemical surface area.The double layer capacitance(C_dl)of the roughened Pt substrate?f _R=424?is about 77 times greater than that of a smooth substrate.The morphology of PANI coatings on the roughened Pt substrates exhibited more uniform and compact.The charge density of PANI coatings on the roughened substrate?f_R=424?increases by about5.6-fold and the interfacial impedance reduces half at the biologically relevant frequency of 1 kHz compared to that of PANI coatings on a smooth substrate.The PANI coatings on the roughened substrates demonstrated higher stability under harsh ultra-sonication than coatings on smooth substrates.These results indicate the potential use of PANI coatings on the roughened substrates as new neural interfaces.