Highly Sensitive, Low Voltage Operation, and Low Power Consumption Resistive Strain Sensors Based on Vertically Oriented Graphene Nanosheets

Abstract Flexible and stretchable electronics are essential module of mobile wearable devices, soft human–machine interfaces, and also e‐skin on biomedical prostheses and biorobotics. Strain sensors, as one of the major part of flexible electronics, have been extensively studied recently. When being used for mobile and long‐term applications, low power consumption and low operation voltage beside high sensitivity and fast response of the sensors are required. Easy integration is also an important aspect to build an internet of things. Here, resistive strain sensors with a maximum gauge factor of 150, a fast response time of about 10 ms, a low operation voltage of 20 mV, and a low power consumption of <8 µW, are demonstrated by introducing easily patternable vertically oriented graphene nanosheets (VGs film) as the sensing material. Ultrasmall strain of 0.07% can be detected with VGs film patterned into 200 µm × 200 µm square array. It is the special structure of the VGs film with a combination of an underlying buffer layer and vertically oriented nanosheets upon it that ensures both the high sensitivity and the low power consumption. To demonstrate the capacities of the sensor, the sensor was applied to monitor the human artery pulses.