One step electrodeposition of composite of PANI-PSS tubules with TiO2 nanoparticles and application as electronic sensor device

Abstract

This paper reports electrodeposition of the composite of Polyaniline-Poly(styrene sulfonate) (PANI-PSS) tubules with TiO2 nanoparticles (PANI-PSS/TiO2 tubules) by using cyclic voltammetry (CV) and demonstrates it as an electronic sensor device. By this method, dispersion of TiO2 particles is ubiquitous in PANI-PSS matrix as characterized by various electrochemical, microscopic (FEG-SEM, FEG-TEM) and spectroscopic (FTIR-IMG) techniques. Electronic properties of the device were explored by CV and in situ conductance measurements. In situ conductance was measured based on the liquid-ion-gated Field Effect Transistor (FET) using PANI-PSS/TiO2 tubules as a conductive channel. During in situ conductivity measurements, it was found that PANI-PSS/TiO2 composite showed a fast redox switching (conversion of the most resistive to the most conductive state of PANI) compared to PANI-PSS. FEG-SEM images showed that polymer was thicker in case of composite and likely to be more porous in nature. All these results, owing to the interaction of PANI-PSS with the TiO2 nanoparticles, were supported by the distinct behavior of composite PANI-PSS/TiO2 in ammonia solutions. Composite sensors showed a significant sensor response for lower concentrations of ammonia up to the ppt/ppb range (50 ppt, 100 ppt, 200 ppt, 10 ppb) based on a liquid-ion-gated FET.