Photo-thermoelectric generator integrated in graphene-based actuator for self-powered sensing function

Smart actuators integrated with sensing functions are taking a significant role in constructing intelligent robots. However, the detection of sensing signals in most actuators requires external electrical power, lacking in the self-powered feature. Herein, we report a graphene-based light-driven actuator with self-powered sensing function, which is designed by integrating a photo-thermoelectric generator into the actuator intelligently. When one part of the actuator is irradiated by near-infrared light, it shows a deformation with bending curvature up to 1.5 cm⁻¹, owing to the mismatch volume changes between two layers of the actuator. Meanwhile, the temperature difference across the actuator generates a voltage signal due to the photo-thermoelectric effect. The Seebeck coefficient is higher than 40 μV/K. Furthermore, the self-powered voltage signal is consistent with the deformation trend, which can be used to characterize the deformation state of actuator without external electrical power. We further demonstrate a gripper and a bionic hand. Their deformations mimic the motions of human hand (or finger), even making complex gestures. Concurrently, they can output self-powered voltage signals for sensing. We hope this research will pave a new way for self-powered devices, state-of-the-art intelligent robots, and other integrated multi-functional systems.