Yang Na, Ji Xingxiang, Sun Juanjuan, Zhang Yu, Xu Qinghua, Fu Yingjuan, Li Hongguang, Qin Menghua, Yuan Zaiwu
State Key Laboratory of Biobased Material and Green Papermaking, School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology (Shandong Academy of Sciences), 250353, Jinan, China.
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, 250100, Jinan, China.
Nanoscale. 2019 May 28;11(20):10088-10096. doi: 10.1039/c9nr02294e. Epub 2019 May 15.
Developing actuators with multi-responsibility, large deformation, and predefined shapes is critical for the application of actuators in the field of artificial intelligence. Herein, we report the preparation of a new type of unimorph actuators containing phenol-formaldelyde resin (PFR) and graphene oxide (GO) using the chiral nematic structure of cellulose nanocrystals (CNCs) as the template. The so-obtained PFR/GO films have a unimorph structure with an asymmetric distribution of GO across the film. They exhibit synchronous responses of both photonic properties and actuation to humidifying/dehumidifying. Moreover, PFR/GO films can be forged into desired shapes by aldehyde treatment, and thereby are able to produce complex movements. In addition, the objects with predetermined shapes show good shape recovery capability upon many wetting-drying cycles, especially through the treatment with formaldehyde. A mechanism model for shape predetermination by aldehyde treatment is suggested based on experimental details. By further designing the predetermined shapes and patterns, such PFR/GO actuators may hold great promise for smart actuation devices of highly complex movements.
