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• A highly sensitive and strain-insensitive fiber-based wearable temperature sensor. • A conductive ligand chemically grafts onto the surface of silver nanowires. • Theoretically calculate the electrical conductivity properties of the ligands. • Silver nanowire network shows high conductivity with decreased junction resistance. • Modified silver nanowires tightly absorb on a stretchable covering yarn. The real-time monitoring of human temperature can facilitate efficient family health supervision, disaster diagnosis, and treatment. To meet these requirements, there is an urgent need to develop fibre-based temperature sensors with high sensitivity, fast response rates, and excellent stability. This study investigated the positive temperature characteristics of a stretchable and strain-insensitive temperature sensor with a chemically modified silver nanowire (AgNW). The regulation of the surface polymer on the AgNWs using a conductive ligand of polyaniline-L-cysteine ethyl ester hydrochloride (PANI-LCO) improved the network conductivity by decreasing the junction resistance. In addition, the pristine flexibility and helicoid structure of a spandex polyurethane (SP) covered yarn substrate proved advantageous for the ultra-stretchability of the temperature sensor. Therefore, the synergistic effect of the PANI-LCO-AgNWs and the substrate endowed the composite fibre-based temperature sensor with a high-temperature coefficient of resistance (TCR) of 47.4%/°C and a high stretchability of up to 120%. Furthermore, this study investigated the actual characteristics of the sensor required for the high-performance monitoring of human temperatures. Moreover, theoretical calculations of the electrical distribution of the PANI-LCO ligands further confirmed the experimental chemical modification. A fibre-based temperature sensor can be integrated and woven or sewn onto a cloth or glove with high adaptability. This work provides an efficient strategy to control the surface chemical structure of metal nanomaterials as well as the design of fibre-based temperature sensors that are promising for wearable healthcare management systems, artificial intelligence, electronic skin, and smart robots. [ABSTRACT FROM AUTHOR]

Poor adhesion between silver nanomaterials and substrates seriously restricts the development of electronic composite devices. In this work, flexible and conductive silver nanowires/fibroin/degummed silk (AgNWs/fibroin/dSF) composite fibers with high adhesion and conductivity via capillarity-assisted assembly for electromagnetic interference (EMI) shielding are designed and fabricated by a facile and scalable all-solution dip-coating method. The nanocomposite fiber possesses high conductivity with a resistance of 8.8 Ω/cm at a low AgNWs/fibroin loading of 19.3 wt%. The assistance of the capillary force in the fiber highly increases the mass of deposited AgNWs. Furthermore, the AgNWs show high adhesion on the fibers in the tape-peel test. The enhanced deposition factors and mechanisms are detailly investigated. Moreover, the composite fibers are further woven into a soft and flexible fabric. The composite fabric shows an absorption-dominated EMI shielding performance with an efficient shielding effectiveness of 38 dB. The capillarity-assisted assembly is an attractive procedure for constructing high-conductive and uniform coatings for a wide application. [Display omitted] [ABSTRACT FROM AUTHOR]