Metal to insulator transition in Conducting Polyaniline/Graphene Oxide composites

TL;DR

This study investigates the metal-insulator transition in Polyaniline/Graphene Oxide composites using broadband dielectric spectroscopy, revealing a transition around 75K influenced by temperature and annealing, with implications for electrical stability.

Contribution

It provides new insights into the charge transfer mechanisms and the effects of annealing on the electrical properties of Polyaniline/Graphene Oxide composites.

Findings

Metal-insulator transition occurs around 75K.

Annealing enhances electrical stability of the composite.

Charge transfer mechanisms are qualitatively described.

Abstract

Broadband Dielectric Spectroscopy (BDS) measurements of P{\omicron}lyaniline/Graphene oxide composites were conducted for an as-prepared and a thermally annealed specimen, respectively, from 15K to room temperature. Electrical conductivity values of the annealed composite display a very modest rise denoting the important contributions of the GO component to achieving electrical stability of the polymer. Patterns of the dc conductivity as a function of temperature also reveal a metal to insulator transition around 75K. The transition is dominated by two key factors; temperature and annealing process. Metal-like and insulating features are subsequently detected, as well, and accordingly described to provide a qualitative inspection of the charge transfer mechanisms involved