A Wearable, Highly Sensitive Piezoresistive Pressure Sensor Based on MXene/NiMoO4@CMF and Mimicking the Hedgehog Skin Spike Structure for Its Real-Time Monitoring of Human Movement

Flexible piezoresistive pressure sensors have received much attention due to their potential for applications in personalized real-time health detection, human-computer interaction, and the Internet of Things (IoT). However, achieving a fast response and high sensitivity while keeping the cost low remains a key concern for researchers. In this paper, we simulated the spiky surface of hedgehog skin by hydrothermal growth of nickel molybdate on a carbonized sponge. Based on this, the MXene material was compounded by a process of immersion and sonication, and thus the MXene/NiMoO4@CMF (MNC) was successfully prepared. After assembly into an MNC piezoresistive pressure sensor, it shows good performance. In terms of sensitivity, the sensitivity is 31.1 kPa–1 in the pressure range of 0–10 kPa, 15.7 kPa–1 in the range of 10–15 kPa, and 3.3 kPa–1 in the range of 15–64 kPa. Moreover, it also has a fast response capability (500 ms) and excellent cyclic stability (95.7%). In addition, we integrated the MNC sensor with the ESP8266 WiFi Module IoT Development Board and an autonomously programmed UI interface. Therefore, it is capable of monitoring human health in real time and displaying abnormal statuses in the UI interface when the test value is outside the normal range. In summary, based on its high sensing performance and integrated application, the MNC sensor has a wide range of potential applications in wearable devices, IoT, and health monitoring.