3D Printing Assisted-Fabrication of Low-Temperature Strain Sensors with Large Working Range and Outstanding Stability

Recently, low-temperature wearable strain sensors, referring to those working at sub-zero temperatures, are attracting increasing attentions. However, the fabrication of low-temperature strain sensors with large working ranges, high sensitivity, and good stability remains a major challenge. In this study, a novel low-temperature wearable strain sensor is fabricated by depositing the silver nanoplates (Ag NPs)/carbon nanotubes (CNTs) composite onto a cured silicone (DS) substrate that is constructed by using a 3D printing technology. The synergistic effect of the Ag NPs with positive temperature coefficient of resistance (TCR) and the CNTs with negative TCR enable the Ag NPs/CNTs/DS strain sensor's TCR value (-1.16 x 10-5 K-1) to approach zero. The Ag NPs/CNTs/DS strain sensor demonstrates a high gauge factor over a large working range (0-100%) and fast response and recovery rates. Simultaneously, the Ag NPs/CNTs/DS strain sensor displays outstanding reproducibility and long-term stability at -40 & DEG;C as well as excellent temperature cycling resistance under cyclic temperature of -40 to 60 & DEG;C. The Ag NPs/CNTs/DS strain sensor is further validated by incorporating into a wireless sensing system for remotely monitoring various human activities at -40 & DEG;C. This work provides wearable strain sensors for monitoring human-machine interaction under low-temperature condition. Constructed by a 3D printing assisted-fabrication, the Ag NPs/CNTs/DS low-temperature strain sensor with a near zero TCR has excellent outstanding reproducibility, long-term stability, and wide working range, which can remotely monitor various human activities at -40 & DEG;C.image