▎ 摘　　要

Graphene oxide (GO)-based actuators provide a material-centered mechanism to enable a broad range of promising applications, especially in artificial muscles, sensors, switches, and energy harvesting devices. However, the current fabrication methods of such actuators require the complicated synthesis of GO-based composites that inevitably break the intrinsic structure of GO. Moreover, the obtained actuators are commonly driven by a strong external stimulus (light, moisture, or electricity) with unavoidable direct contact, which results in the decomposition of the GO-based composites, and thus reduces the device lifetime. To address the aforementioned challenges and limitations, we demonstrate a simple and generic electrostatic actuation principle for the design and fabrication of pristine GO film-based contactless actuators with a fast actuation response, good reversible actuation, and high stability. The resulting GO film-based actuators can be driven easily by almost all commonly charged objects. Two applications are demonstrated, one is a smart "radar'' made by a 3 x 3 GO filmstrip array for tracking the motion of objects, and the other one is GO filmbased "dancers'' obtained from Chinese paper-cuts. The presented contactless actuation principle and the simple fabrication process open a new avenue for the design and development of GO-based actuators, which can be easily extended to the fabrication of other smart devices for motion detection or energy harvesting.