Hydrostatic pressure sensors based on carbon spheres dispersed in polyvinyl alcohol prepared using hexadecyltrimethylammonium bromide as surfactant and water as solvent

We report on hydrostatic pressure sensors based on carbon spheres–polyvinyl alcohol composites prepared in aqueous medium. The carbon spheres were dispersed in water applying a surfactant (hexadecyltrimethylammonium bromide) and deposited onto interdigitated electrodes of tin. The pressure dependence of the conductance of the devices is investigated. An almost linear behavior of the sensitivity of 6.8% between 90–135 kPa is observed for the composite prepared from a solution of 15 mg mL⁻¹ of undoped-carbon spheres, representing a significant improvement with respect to devices based on composites with non-dispersed carbon spheres. (papers)