The Influence of Tensile Stress on Polyaniline as Strain Sensor

In this letter, we report a first-principles study to investigate the influence of tensile stress on HCl-doped emeraldine-base polyaniline (PANI-Cl) as strain sensors by means of dispersion-corrected density functional theory computations. Our results show that up to a strain of ~17%, the strain increases linearly with the tensile stress. The analysis of the band gap changes and the density of states variations at Fermi level with tensile stress provide insight into the role that the tensile stress plays in affecting the conductivity of PANI-Cl. The sensitivity of PANI-Cl as strain sensors is also calculated, which show a stress dependence. We hope that our findings may open new opportunities in fabricating conducting polymer-based strain sensors.