Correlation between electrical resistance and defect concentration in graphite under non-hydrostatic stress

Abstract

Combination of Raman spectroscopy and electrical resistance measurements carried out under non-hydrostatic stress reveals a direct correlation between the transport properties and the concentration of structural defects in graphite, as measured by the relative intensity of the D and D′ bands. We have found that the piezoelectric behavior of highly defected specimens can be modulated through changes in the microstructure, essentially by affecting the crystallite size. The observed correlation suggests some interesting applications based on the use of Raman spectroscopy as a technique for estimating the relative electrical behavior of microstructurally controlled graphite samples under quasi-uniaxial strain conditions.