Multifunctional Sensors Based on a Silver Nanowires/PDMS Aerogel Composite

Abstract

A multifunctional sensor that combines force/strain and temperature sensing functions into a single element is much more advantageous in saving space and avoiding technical complexity than integrating multiple sensing elements together. In this work, we realized force/strain and temperature sensing with a lightweight aerogel composite of silver nanowires and poly(dimethylsiloxane) (AgNWs/ PDMS). The AgNWs/PDMS aerogel composite was prepared using a sugar cube as a sacrificial template, and the AgNWs were uniformly distributed on the inner surface of the porous structure. Multifunctional sensors made of the AgNWs/PDMS aerogel composite show sensitive responses to various stimuli in resistivity. When serving as a force/strain sensor, it exhibits an excellent sensitivity (gauge factor ∼32) in the strain range of 60−90%. While working as a temperature sensor, the multifunctional sensor presents a temperature sensitivity of 0.33%/°C. Moreover, the porous aerogel structures can also be used to absorb pollutants such as oil and organic solvents, which will make them revive once their sensing function degrades. The proposed composite shows great potential in multifunctional wearable devices, sensor arrays for the Internet of things, and pollutant cleaning.

Lightweight and Mechanically Robust MXene/Polyimide/Silver Nanowire Composite Aerogels for Flexible Piezoresistive Sensors

“…Silver nanowires (AgNWs) with one-dimensional structure and excellent intrinsic conductivity are also a good material choice for obtaining high-performance aerogel piezoresistive sensors. 22,36−38 Han et al 38 fabricated a AgNWs/poly-(dimethylsiloxane) composite aerogel by using a sugar cube as a sacrificial template, and the AgNWs were uniformly distributed on the inner surface of the obtained porous structure. The composite aerogel exhibits excellent sensitivity [gauge factor (GF) of ∼32] in the strain range of 60−90%.…”

“…Since there are also a large number of hydrophilic functional groups on the surface of MXene nanosheets, the PI can be selected as a material component to improve the mechanical properties of MXene-based aerogel. , For example, Liu et al fabricated a conductive PI nanofiber/MXene composite aerogel with “layerstrut” bracing hierarchical nanofibrous cellular structure, the composite aerogel exhibits outstanding sensing capacity up to 90% strain (corresponding 85.21 kPa), ultralow detection limit of 0.5% strain (corresponding 0.01 kPa), and robust fatigue resistance over 1000 cycles. Silver nanowires (AgNWs) with one-dimensional structure and excellent intrinsic conductivity are also a good material choice for obtaining high-performance aerogel piezoresistive sensors. ,− Han et al fabricated a AgNWs/poly­(dimethylsiloxane) composite aerogel by using a sugar cube as a sacrificial template, and the AgNWs were uniformly distributed on the inner surface of the obtained porous structure. The composite aerogel exhibits excellent sensitivity [gauge factor (GF) of ∼32] in the strain range of 60–90%.…”

Wearable and Cost-Effective Pressure Sensor Based on a Carbon Nanotube/Polyurethane Sponge for Motion Detection and Gesture Recognition

“…Flexible sensors have received widespread attention from researchers due to their excellent characteristics such as being lightweight, compressible, and wearable. These sensors have been widely used in various fields, including human motion detection, − health monitoring, − handwriting typing, − and human–machine interaction. − Flexible sensors can be broadly classified into different sensing mechanisms, namely, piezoresistive, − capacitive, − piezoelectric, − and triboelectric. − Among them, piezoresistive sensors have been recognized as the ideal choice for next-generation wearable devices, human–machine interaction, and health monitoring due to their advantages of a simple structure, fast response, and convenient signal acquisition. To obtain both greater sensitivity and a wider detection range, many studies have proposed improvements to piezoresistive sensors.…”

Dual conductive network sensors based on an MXene/PDES supramolecular elastomer and their performance

“…1,2 The ideal wearable strain sensor should have a broad limit of detection (LOD), high sensitivity (gauge factor, GF), fast response, high linearity, and high durability. 3 Many researchers have reported wearable strain sensors by mixing metal nanoparticles, 4,5 graphene, 6,7 carbon nanotubes, 8 silver nanowires, 9,10 or other electronically conductive materials with traditional flexible polymers such as natural rubber (NR), 11–15 polydimethylsiloxane (PDMS), 16–19 and polyurethane (PU), 20–23 but saw little success. Usually, the mixing processes are divided into two strategies: one is directly dispersing conductive nanomaterials in the polymer matrix, and the other is constructing specific conductive pathways of nanomaterials in the polymer matrix.…”