湿度驱动的高性能致动器与传感器:界面工程调控氧化石墨烯与乙基纤维素（英文）

Moisture-triggered actuator and detector with high-performance: interface engineering of graphene oxide/ethyl cellulose

致动器可以将外界环境中的能量直接转换成机械能,在能源应用和智能设备上有着广阔的应用前景.但迄今为止,界面接触强度较低以及湿度响应是制约驱动器发展的瓶颈问题,限制了其实际应用.本文从实验上构建了优化双层膜结构驱动器界面接触的模型,所构建的氧化石墨烯与乙基纤维素双层膜致动器对于环境湿度的变化具有快速可逆的响应性,同时可以驱动压电探测器.此结构模型中,氧化石墨烯与乙基纤维素之间通过化学键结合,成功地构建了机械强度和韧性协同增强的双层膜驱动器.由于氧化石墨烯的优异吸湿特性,同时伴随着明显的体积膨胀,引起双层膜驱动器对于湿度变化超过90度弯曲的响应.同时,构建的压电传感器具有优异可逆性的0.1 V开路电压.我们期望湿度响应驱动器和传感器有望在各种多功能纳米系统中得到应用并能服务于智能设备领域.

Actuators that can directly convert other forms of environmental energy into mechanical work offer great application prospects in intriguing energy applications and smart devices. But to-date, low cohesion strength of the interface and humidity responsive actuators primarily limit their applications. Herein, by experimentally optimizing interface of bimorph structure, we build graphene oxide/ethyl cellulose bidirectional bending actuators — a case of bimorphs with fast and reversible shape changes in response to environmental humidity gradients. Meanwhile, we employ the actuator as the engine to drive piezoelectric detector. In this case, graphene oxide and ethyl cellulose are combined with chemical bonds, successfully building a bimorph with binary synergy strengthening and toughening. The excellent hygroscopicity of graphene oxide accompanied with huge volume expansion triggers giant moisture responsiveness greater than 90 degrees. Moreover, the open circuit voltage of piezoelectric detector holds a peak value around 0.1 V and exhibits excellent reversibility. We anticipate that humidity-responsive actuator and detector hold promise for the application and expansion of smart devices in varieties of multifunctional nanosystems.