Interchangeable films made from cellulose acetate and different types of carbon nanotubes with humidity sensing capabilities

Abstract

This study presents a novel manufacturing technique for cellulose-based/multi-walled carbon nanotube film (CMF), which produces high-performance, flexible humidity sensors with fast reaction sensing in response to the growing need for wearable technology and environmental monitoring. The technique allows for the production of several kinds of sensors by varying the substrates on which the carbon nanotubes are attached. Because of its exceptional intrinsic qualities as well as its ability to produce films, cellulose acetate was chosen as a support for the implementation of this assembly. Furthermore, we have a great deal of structural flexibility with cellulose acetate since it is easily transformed into cellulose and then into carboxyl cellulose by TEMPO-mediated oxidation. Thus, depending on the chemical structure of each type of substrate, this structural diversity will produce sensors with varying sensitivity and functionality. Furthermore, the range of the examined samples has been further extended by the addition of amino groups to the nanotubes by chemical functionalization. The cellulose-based/CNT films exhibit a response time of only 100 s and demonstrate high reversibility, with sample recovery times exceeding 150 s. Considering these promising results, a wide range of application areas, including wearable technology, environmental tracking, and artificial skin, hold great potential for this straightforward manufacturing technique.