Multiwalled Carbon Nanotubes Films for Sensing Purpose

Films of multiwalled carbon nanotubes (MWCNTs) are proposed as the sensing element of low-cost sensors for the detection of temperature, pressure and water droplets. Liquid solutions of functionalized MWCNTs are vacuum filtered to produce freestanding films of randomly oriented MWCNTs, known as buckypapers, which are patterned in strips of several mm size. The electrical conduction of the buckypaper is highly sensitive to the environmental conditions. It increases for rising temperature or when a pressure is applied; conversely, it is decreased under tensile strain or by exposure to water droplets. The experimental data presented in this work confirm the suitability of buckypapers for multipurpose sensors able to detect different physical quantities simultaneously.