Improving the electrochemical behavior of sustainable polyaniline titanium dioxide composite by intercalation of carbon nanotubes

Abstract

Polyaniline titanium dioxide (PANi-TiO2) composite had improved electrochemical behavior by intercalation of varied carbon nanotubes (CNTs): from 0 wt% to 30 wt%, compared to aniline. Those composites were coated on the titanium substrate to form PANi-TiO2-CNTs/Ti by using a binder agent. Material properties were characterized by IR spectra, X-ray diffraction and thermal analysis. The scanning electron microscope (SEM) images explained that the composite existed in uniform fibers with diameter of about 100 nm if content of CNT was 20–30 wt%. Electrical conductivity measurement, electrochemical impedance spectroscopy (EIS) and cyclic voltammograms showed their excellent electrical performance: electrical conductivity reached approximately 10−1 S/cm, and the resistances of those composite layers were reduced from 18 to 27 times compared to that without CNTs. Warburg diffusion was found by EIS analysis with coefficient data ranging from 10−15 to 10−16 cm2/s only for composites containing CNTs on which also no adsorption resistance occurred. The potentiodynamic and galvanodynamic polarizations explained that the composite contained 20% CNTs, exhibiting a better cyclic voltammetry (CV) diagram because of higher responding current density and a better performance because of yielding a higher current density (300 μA/cm2) at 250 mV versus silver/silver chloride reference electrode in comparison with the other obtained composites in this study, respectively.

Keywords

• anode materials for mfc
• cyclic voltammetry
• dynamic current polarization
• electrochemical impedance spectroscopy
• pani-tio2-cnts nanocomposite