分类: 材料科学 >> 纳米科学和纳米技术 提交时间: 2017-01-10
摘要: Spongy graphene paper with inside foldable corrugated structure is fabricated by electrothermal reduction of the oxygen-containing groups inside RGO paper. Reversible macroscopical length contraction of the spongy graphene paper with strain of 2.4% under 10V voltage is exhibited, mostly attributed to the deformation of corrugated structures.
分类: 材料科学 >> 纳米科学和纳米技术 提交时间: 2017-01-10
摘要: Bimorph actuators, consisting of two layers with asymmetric expansion and generating bending displacement, have been widely researched. Their actuation performances greatly rely on the differences of coefficient of thermal expansion (CTE) between the two material layers. Here, by introducing a spongy graphene (sG) paper with large negative CTE as well as highly electrical-to-thermal property, an electromechanical sG/PDMS bimorph actuator is designed and fabricated, showing ultra-large bending displacement output under the low voltage stimulation (curvature of about 1.2cm-1 under 10V voltage for 3s), high displacement-to-length ratio (~0.79), and vibration motion under AC voltage (up to 10Hz), which is much larger and faster than that of the other electromechanical bimorph actuators. Based on the sG/PDMS bimorph serving as the “finger”, a mechanical gripper is constructed to realize the fast manipulation of the objects under 0.1 Hz square wave voltage stimulation (0~8V). The designed bimorph actuator coupled with ultra-large bending displacement, low driven voltage, and ease fabrication, may open up substantial possibilities for the utilization of the electromechanical actuator in practical biomimetic device applications.