The importance of potential range choice on the electromechanical response of cellulose-carbon nanotube fibers

Recently, an important focus of material research has been aimed at more sustainable smart materials with biodegradable, biocompatible properties such as those based on cellulose (Cell), made stimuli-responsive with the addition of multiwall carbon nanotubes (CNT). Formulated as fibers, such materials have potential applications in smart clothing and wearable's in actuation or sensing function. In order to ensure maximum performance, an optimal driving voltage and regime must be chosen. In addition to the quantitative effects, the actuation response also qualitatively and mechanistically changes, depending on the voltage range. The linear actuation measurements combined with cyclic voltammetry and square wave potential steps were performed in aqueous lithium bis(trifluoromethane)sulfonimide solution. The Cell-CNT fiber actuation response properties were investigated at different potential ranges: 0.8-0.0 V, 0.8 V to - 0.3 V, 0.8 V to - 0.55 V and 0.65 V to - 0.6 V, observing a change in actuation direction between the ranges. Not just the potential range but also the driving frequency had an impact on the response, therefore, the selection of driving parameters is shown to be critical for controllable performance.