Fabrication of Janus GO/rGO humidity actuator by one-step electrochemical reduction route

Abstract

Graphene oxide (GO) is an insulator and should be converted to reduced graphene oxide (rGO) paper structure by reduction to provide electrochemical activity. This work maintains an essential route to fabricate rGO paper. Hence, the first aim of this study is to produce rGO paper by one-step electrochemical reduction of GO paper by the optimization of quality parameters. Humidity actuators produce mechanical feedback if the moisture is exposed to their surface. To provide this kind of response, Janus materials are good nominated due to their asymmetric surface character in terms of hydrophilicity. GO paper can be performed for this application by converting one side to rGO layers. By this approach, hydrophobic rGO and hydrophilic GO sheets of the Janus system are generated, in which moisture flow swells the GO side and causes bending motion of the material through the rGO layer. In this work, Janus GO/rGO paper has been prepared by one-step electrochemical reduction of one side of the GO paper. Characterization of the samples has been carried out using numerous techniques. Humidity actuator experiments have indicated that Janus GO/rGO paper is acting circularly and there is an exponential relationship between relative humidity and circularly-oriented bending angle of the actuator.