The preparation of graphene/polyethylene oxide/sodium dodecyl sulfate composite humidity sensor via electrohydrodynamic direct-writing

Abstract

Abstract Continuous accurate deposition of composites can be achieved by electrohydrodynamic direct-writing, but the eddy flow with the Weissenberg effect may affect stable jet, which is important in electrohydrodynamic direct-writing. So electrohydrodynamic direct-writing of micro-scale graphene/polyethylene oxide/sodium dodecyl sulfate composite (the pumping and preparation of graphene composites based on the Weissenberg effect) is studied for the first time. This paper explores the effects on the morphology of graphene composite films such as voltage and collection distance. In addition, the composite is firstly used in a resistance-based humidity sensor. It is found that the composite films are very sensitive to humidity when its width is less than 200 µ m due to its porous structure and high specific surface area. When the width of the composite films is about 100 µ m, its resistance decreases rapidly as the humidity increases from 63% RH to 100% RH (the response time is less than 2.5 s).