title: Polybenzoxazole Nanofiber-Reinforced Moisture-Responsive Soft Actuators.
abstract: Hydromorphic biological systems, such as morning glory flowers, pinecones, and awns, have inspired researchers to design moisture-sensitive soft actuators capable of directly converting the change of moisture into motion or mechanical work. Here, we report a moisture-sensitive poly(p-phenylene benzobisoxazole) nanofiber (PBONF)-reinforced carbon nanotube/poly(vinyl alcohol) (CNT/PVA) bilayer soft actuator with fine performance on conductivity and mechanical properties. The embedded PBONFs not only assist CNTs to form a continuous, conductive film, but also enhance the mechanical performance of the actuators. The PBONF-reinforced CNT/PVA bilayer actuators can unsymmetrically adsorb and desorb water, resulting in a reversible deformation. More importantly, the actuators show a pronounced increase of conductivity due to the deformation induced by the moisture change, which allows the integration of a moisture-sensitive actuator and a humidity sensor. Upon changing the environmental humidity, the actuators can respond by the deformation for shielding and report the humidity change in a visual manner, which has been demonstrated by a tweezer and a curtain. Such nanofiber-reinforced bilayer actuators with the sensing capability should hold considerable promise for the applications such as soft robots, sensors, intelligent switches, integrated devices, and material storage.
authors.affiliation: Key Laboratory of Microsystems and Microstructures Manufacturing, Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin, 150080, China.
authors.forename: Meiling
authors.initials: M
authors.lastname: Chen
authors.affiliation: Key Laboratory of Microsystems and Microstructures Manufacturing, Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin, 150080, China.
authors.forename: Johannes
authors.initials: J
authors.lastname: Frueh
authors.affiliation: Key Laboratory of Microsystems and Microstructures Manufacturing, Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin, 150080, China.
authors.forename: Daolin
authors.initials: D
authors.lastname: Wang
authors.affiliation: Key Laboratory of Microsystems and Microstructures Manufacturing, Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin, 150080, China. xiankunlin@hit.edu.cn.
authors.forename: Xiankun
authors.identifier: http://orcid.org/0000-0001-6936-4812
authors.initials: X
authors.lastname: Lin
authors.affiliation: Key Laboratory of Microsystems and Microstructures Manufacturing, Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin, 150080, China. xiehui@hit.edu.cn.|State Key Laboratory of Robotics and Systems, School of Mechatronics Engineering, Harbin Institute of Technology, Harbin, 150080, China. xiehui@hit.edu.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Xie
authors.affiliation: Key Laboratory of Microsystems and Microstructures Manufacturing, Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin, 150080, China. qianghe@hit.edu.cn.
authors.forename: Qiang
authors.identifier: http://orcid.org/0000-0002-3557-6865
authors.initials: Q
authors.lastname: He