Electrical conductivity behavior of wet spun graphene fiber

In this paper, we report the conductivity behavior in the insulating phase at zero magnetic field. We have theoretically investigated the temperature dependence of the electrical conductivity of wet spun graphene fiber and its composites. The temperature dependence of electronic conduction follows the law $\sigma\sim\exp(E_0/E)^m$. Indeed, the electronic conduction is dominated by the coexistence of two regimes: Efros–Shklovskii variable range hopping mechanism where $m$ = 1/2 and the activated mechanism where $m$ = 1. By using two different methods: the numerical method based on the calculation of the percentage deviation Dev (%) and the conductance curve derivative analysis method which is based on the logarithmic derivative function $W=d\ln\sigma/d\ln E$, we have found the exponent $m$ is close to 1.