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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]

Abstract Nickel cobalt oxide is widely studied as the electrocapacitive material for energy storage devices because of its high electrical conductivity and multiple transition states for generating abundant Faradaic redox reactions. Constructing well-defined core/shell structures with effective charge transfer path and large surface area is one of the feasible ways to develop efficient electrocapacitive materials. This study proposes a novel insight at the first time to investigate the electrocapacitive performance of the NiCo 2 O 4 core/shell electrodes comprising different core morphologies of one-dimensional (1D) nanowire (NW) and two-dimensional (2D) nanosheet (NS). The nickel molybdenum oxide shell synthesized on different NiCo 2 O 4 cores shows similar morphologies, suggesting the core structure has limited influences on the growth of the shell. Simple sheet-on-wire and sheet-on-sheet configurations are therefore obtained for the core/shell structures with 1D NW and 2D NS cores, respectively. A specific capacitance (C F) of 5.53 F/cm2 is obtained at 5 mV/s for the core/shell electrode composed of the 1D NW core, along with the C F retention of 65% after 2000 cycles repeated charge/discharge process. This study provides a novel viewpoint for constructing efficient energy storage devices via carefully designing the core morphology for the core/shell structures as the electrocapacitive material. Highlights • The core morphology effects on core@shell structures and performances are studied. • Nanowire (NW) and nanosheet (NS) are made as core for NiCo 2 O 4 @NiMo x O y structures. • NiCo 2 O 4 @NiMo x O y structures show simple combination of core and shell morphologies. • NiCo 2 O 4 NW@NiMo x O y electrocapacitively performs better than NiCo 2 O 4 NS@NiMo x O y. • The 1-D NW core provides efficient charge transfer paths and better performances. [ABSTRACT FROM AUTHOR]