High Sensitivity and a Wide Sensing Range Flexible Strain Sensor Based on the V‑Groove/Wrinkles Hierarchical Array
journal contributionposted on 2022-05-11, 21:44 authored by Jin Ji, Chengpeng Zhang, Shaohua Yang, Yongzhi Liu, Jilai Wang, Zhenyu Shi
Flexible strain sensors occupying a large part of human body detection and wearable electronics, which have a wide sensing range and high sensitivity, are crucial in fully monitoring human motion signals. This study proposed a strategy to construct flexible strain sensors based on the V-groove/wrinkles hierarchical array. The V-groove array was prepared on a polydimethylsiloxane (PDMS) substrate through mold transfer printing. The gold film was sputtered on the prestretching PDMS substrate, and the V-groove/wrinkles hierarchical array was formed after strain release. Compared with the sensors based on single-scale wrinkle structures and a V-groove array, the fabricated strain sensor with the hierarchical array showed high sensitivity (maximum gauge factor up to 2,557.71) and a wide sensing range (up to 45%). In addition, the dynamic characteristics of the sensor were investigated in detail, indicating that the sensor had a fast response (less than 130 ms), a low detection limit (0.1% strain), and good stability (almost no performance loss after 10,000 cycles). In practical applications, the sensor was used to detect sizable physical motion and weak physiological signals, demonstrating great potential application value in human motion detection. This study could provide new ideas for preparing high-performance flexible strain sensors.
wide sensing rangeweak physiological signalsscale wrinkle structuresmold transfer printingmaximum gauge factorlow detection limithuman motion detectionhuman body detection000 cycles ).wrinkles hierarchical array130 ms ),fabricated strain sensorv ‑ grooveprestretching pdms substratestrain ),groove arraystrain releasewearable electronicsstudy proposedsensors basedpreparing highpractical applicationsperformance losslarge parthigh sensitivitygood stabilitygold filmfast responsedynamic characteristics45 %).