ZnO Nanostructure-Based Flexible Pressure Sensors Deposited on Filter Paper for Wearable Application

Flexible pressure sensors have broad prospects in smart wearables, healthcare, and human-computer interaction. Nevertheless, flexible pressure sensors still face numerous thorny challenges. It has become a crucial problem to skillfully design and successfully achieve flexible pressure sensors with both a high sensing range and ultrahigh sensitivity. The sensor is designed and realized with inspiration drawn from the layered microstructure of human skin, and hierarchical structure flexible pressure sensors are fabricated, where PDMS microstructures/MWCNTs act as the top electrode, filter paper/ZnO nanostructures/MWCNTs act as the intermediate active layer, and an Ag interdigitated electrode acts as the bottom electrode. The sensing performance of the sensor is investigated to develop the application of pressure sensors for human health detection in daily life, and a pressure sensor array is prepared to investigate the detection of spatial pressure distribution. Sensors based on paper and PDMS can achieve low-pressure detection (30 Pa), high sensitivity (261.38 kPa^-1), fast response time (∼73.8 ms), and excellent cyclic stability (10 000 cycles). Finally, the sensor demonstrates its functionality by lighting up a small lamp, which confirms that the as-prepared pressure sensor has excellent application scenarios and is beneficial for the development of flexible electronic devices.