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Lightweight artificial muscles with large strain and large stress output have great application prospects in robotics, rehabilitation, prosthetic, and exoskeletons. Despite the excellent performance of carbon nanotube‐based artificial muscles in recent years, their widespread use is hindered by the high manufacturing costs associated with carbon nanotubes. In this paper, the study introduces a novel approach by developing artificial muscles based on pure conductive polymer coiled yarns. This achievement is facilitated by the successful fabrication of high‐strength conductive polymer microfibers. Furthermore, the study elucidates the molecular structural changes occurring during electrochemical processes that induce a substantial radial volume expansion in the microfibers. The resultant anisotropic volume change is magnified by the coiled yarn, yielding a remarkable contractile strain exceeding 11% at a high stress of 5 MPa, equivalent to lifting loads more than 4000 times their own masses, all achieved with a low input voltage of 1 V. Additionally, these conductive polymer‐based artificial muscles exhibit hydration‐induced contraction up to 33%, with swift recovery through electrical heating, leveraging their intrinsic high conductivity. This breakthrough positions high‐performance conductive polymer microfibers as a promising cost‐effective alternative to carbon nanotubes, establishing them at the forefront of lightweight artificial muscles. [ABSTRACT FROM AUTHOR]

Current research about resistive sensors is rarely focusing on improving the strain range and linearity of resistance-strain dependence. In this paper, a bi-sheath buckled structure is designed containing buckled carbon nanotube sheets and buckled rubber on rubber fiber. Strain decrease results in increasing buckle contact by the rubber interlayer and a large decrease in resistance. The resulting strain sensor can be reversibly stretched to 600%, undergoing a linear resistance increase as large as 102% for 0-200% strain and 160% for 200-600% strain. This strain sensor shows high linearity, fast response time, high resolution, excellent stability, and almost no hysteresis. [ABSTRACT FROM AUTHOR]

Silicon monoxide/graphite/multi-walled carbon nanotubes (SiO/G/CNTs) material was prepared by ball milling followed by chemical vapor deposition method and characterized by X-ray diffraction, scanning electron microscopy (SEM), galvanostatic charge-discharge, and AC impedance spectroscopy, respectively. The results revealed that SiO/G/CNTs exhibited an initial specific discharge capacity of 790 mAh g with a columbic efficiency of 65%. After 100 cycles, a high reversible capacity of 495 mAh g is still retained. The improved electrochemical properties were due to beneficial SEI by the SEM and EIS results. [ABSTRACT FROM AUTHOR]

Yarn artificial muscles offer an exciting avenue to replicate the extraordinary efficiency of biological muscles, converting chemical energy directly into mechanical work. Nevertheless, realizing the chemical‐mechanical energy conversion has posed significant challenges. In this study, a novel approach for harnessing direct catalysis to power yarn artificial muscles within a one‐compartment aqueous system is introduced. This research distinguishes itself through an innovative actuation mechanism using nanoscale catalytic particles. These nanoparticles synthesized and integrated onto the yarn surface act as a chemical trigger for muscle actuation. Notably, the resulting yarn muscle demonstrates a reversible tensile stroke of nearly 4% in ≈20 s. By bridging the gap between chemical catalysis and mechanical performance, this study paves the way for innovative applications in fields ranging from robotics to biomedical devices. [ABSTRACT FROM AUTHOR]

Flexible fuel cells show great prospects as a power source in wearable devices due to their high efficiency and good reliability. Herein, a wire‐shaped fuel cell is designed by achieving two main breakthroughs; one is the fabrication of the catalyst‐loaded current collector for wire‐shaped electrodes, and the other is the membrane‐free configuration design according to a new fuel reaction mechanism. Successfully, a flexible wire‐shaped membraneless fuel cell (WFC) is fabricated for the first time by integrating a biscrolled carbon nanotube (CNT)@ Fe3[Co (CN)6]2 cathode and CNT@ nickel particles anode into a silicone tube with a liquid H2O2 fuel electrolyte. The resulting flexible WFC shows an open‐circuit potential (OCP) of 0.88 V and a power density of 6.28 mW cm−2. Moreover, it can retain the structural integrity and stability under repeated bending deformation. Hopefully, this article will pave the way for the next‐generation reliable wearable electronics. [ABSTRACT FROM AUTHOR]

The increasing demand for wearable glucose sensing has stimulated growing interest in stretchable electrodes. The development of the electrode materials having large stretchability, low detection limit, and good selectivity is the key component for constructing high performance wearable glucose sensors. In this work, we presented fabrication of stretchable conductor based on the copper coated carbon nanotube sheath-core fiber, and its application as non-enzymatic electrode for glucose detection with high stretchability, low detection limit, and selectivity. The sheath-core fiber was fabricated by coating copper coated carbon nanotube on a pre-stretched rubber fiber core followed by release of pre-stretch, which had a hierarchically buckled structure. It showed a small resistance change as low as 27% as strain increasing from 0% to 500% strain, and a low resistance of 0.4 Ω·cm−1 at strain of 500%. This electrode showed linear glucose concentration detection in the range between 0.05 mM and 5 mM and good selectivity against sucrose, lactic acid, uric acid, acrylic acid in phosphate buffer saline solution, and showed stable signal in high salt concentration. The limit of detection (LOD) was 0.05 mM, for the range of 0.05–5 mM, the sensitivity is 46 mA·M−1. This electrode can withstand large strain of up to 60% with negligible influence on its performance. [ABSTRACT FROM AUTHOR]

A highly stretchable, resistive strain sensor composed of a bi‐sheath structure is described by Jianning Ding, Linqi Shi, Zunfeng Liu, and co‐workers in article number 1702134. Buckles of a carbon nanotube sheath contact with one another under compression of an underlying buckled elastomer sheath, which is co‐axially coated on a rubber fiber. Stretching separates the buckles, resulting in linear increase of resistance with strain. [ABSTRACT FROM AUTHOR]

Spinnable carbon nanotube arrays (spinnable CNTs) combine the multifunctional properties of CNTs and impart unique properties that are absent in disordered CNTs, such as anisotropy, high electrical conductivity, large specific surface area, super hydrophobicity, and high absorbance. Thermal chemical vapor deposition (CVD) is the main method for the preparation of spinnable CNTs. In CVD, the roles of the catalyst, substrate, temperature, gas flow rates, reaction time, and carbon sources have been studied intensively to understand their effect on the process and to identify the precise conditions for high spinnability. However, most studies have been conducted under atmospheric pressure, neglecting the crucial impact of pressure that is often discussed in semiconductor processes. To investigate the effect of pressure, we fabricated spinnable CNTs by thermal CVD in the pressure range of 1–30 kPa. Results showed that the reaction pressure not only influenced the spinnability of the CNT arrays, but also effectively reduced the optimal temperature to 540 °C, which was approximately 100 °C lower than that in the atmospheric process. In addition, the process executed at lower temperature and low pressure can suppress the leakage of flammable explosive gases, and it is more energy-saving and environmentally friendly. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The electronic structure of (5,5)/(10,0) single wall carbon nanotube intramolecule junction under electric field is investigated based on the density functional calculation. The variations in the density of states (DOS) as well as in the local DOS of the junction are direction depended on the longitudinal electric field. The delocalization of electrons can be enhanced by transverse electric field, for example a peak is resulted at the Fermi level in the DOS. The Mulliken charges redistribute under the external electric field. Their population indicates that the charges concentrate at the interface. Furthermore, some discussions are made on the structure deformation, the highest occupied molecular orbital and the lowest unoccupied molecular orbital. [Copyright &y& Elsevier]

Success in making artificial muscles that are faster and more powerful and that provide larger strokes would expand their applications. Electrochemical carbon nanotube yarn muscles are of special interest because of their relatively high energy conversion efficiencies. However, they are bipolar, meaning that they do not monotonically expand or contract over the available potential range. This limits muscle stroke and work capacity. Here, we describe unipolar stroke carbon nanotube yarn muscles in which muscle stroke changes between extreme potentials are additive and muscle stroke substantially increases with increasing potential scan rate. The normal decrease in stroke with increasing scan rate is overwhelmed by a notable increase in effective ion size. Enhanced muscle strokes, contractile work-per-cycle, contractile power densities, and energy conversion efficiencies are obtained for unipolar muscles. [ABSTRACT FROM AUTHOR]

A washable and sensitivity flexible piezoresistive pressure sensor is necessary to realize the practical application in intelligent wearable field. However, it remains a great challenge to prepare piezoresistive pressure sensor with high sensitivity and superior washable stability. Herein, a 3D porous structure carbon nanotube (CNT)/carbon black (CB) sponge piezoresistive pressure sensor was constructed by salt-template and physical absorption method. The CNT/CB sponge with porous structure exhibited excellent compression cycle stability (372 ± 6 kPa), and lower hysteresis (≤9.38 % residual strain). Impressively, the assembled CNT/CB sponge pressure sensor showed high sensitivity of 164 kPa−1 (0–2.1 kPa), 8000 times long-term cycles stability and superior washable stability. The pressure sensor was used for human motion monitoring, such as: pulse, joint bending, micro-expression, foot type recognition and gesture detection. Furthermore, the pressure sensor can be connected with bluetooth module to monitor the gait characteristics of human movement in real time to prevent foot membrane inflammation. [Display omitted] [ABSTRACT FROM AUTHOR]

Monodomain liquid crystal elastomers with excellent reversible contraction deformation under a heat stimulus have broad application prospects in artificial muscles, soft robots, and micromechanical systems. Greater control can be achieved in a flexible actuation process through the generation of Joule heat by electricity. Herein, a highly conductive liquid crystal elastomer fibre actuator (c-LCF) was continuously prepared via liquid-phase drawing, with a conductivity of up to 12.5 S/m at 30 ℃. High conductivity is realised by the semi-wrapping combination of the main-chain liquid crystal prepolymer and carbon nanotube/carbon black to achieve a high-concentration dispersion of multi-dimensional conductive carbon nanomaterials. The fabricated c-LCF had a negative temperature coefficient, which is favourable for controllability and fast electrothermal actuation. The c-LCF contracted by approximately 30 % under a load of 1 MPa with a current of 9 mA (28 V/cm, 252 mW/cm). Its output power density reached 0.94 kJ/kg, indicating a better performance than biological muscle fibres; thus, it can be used to construct high-load bio-muscles. The different structures constructed by the c-LCF and fibre bundles can realise different electric actuation modes. In addition, fast driving can be realised using an elastic instability structure. The applications of liquid-crystal elastomers will be significantly broadened by this research. [Display omitted] • A highly conductive liquid crystal elastomer fiber actuator is prepared continuously. • The high conductivity is realized by the semi-wrapping combination of CNT. • The fabricated c-LCF has a negative temperature coefficient character. • The c-LCF can contract by approximately 30 % under a load of 1 MPa. [ABSTRACT FROM AUTHOR]

In this study, a new laminate CNT sheet/AgNWs/CNT sheet structure is proposed to improve the rate performance of solid-state long linear supercapacitors. The fabricated 16 cm long linear supercapacitor with a ∼40 μm diameter electrode has a specific length capacitance of 6.26 mF cm −1 at 20 mV s −1 . Further, it exhibits good capacitance behavior even at scan rate of 100 mV s −1 . AgNWs/CNT sheet improves the axial electron transport greatly and consequently boosts the rate performance of linear supercapacitor. Serially connected linear supercapacitors were found to possess good electrochemical performance, and the device was able to illuminate an electronic watch successfully. This study provides an effective method to enhance the rate performance of long linear supercapacitors, which has potential applications in wearable and portable electronics and micro robots. [ABSTRACT FROM AUTHOR]

• Inspired by human skin, a novel dual spinosum microstructured sensor was fabricated. • The sensor demonstrated high pressure sensitivity and excellent cycle stability. • Our sensor has excellent capabilities in temperature and texture roughness detection. The bionic sensor imitates the function of biological perception of external stimuli, which have attracted tremendous attentions. However, it remains a great challenge to prepare wearable bioinspired sensor with highly sensitive at low pressure and with multifunctional sensory capabilities. Herein, inspired by the spinosum structure of human skin, a novel surface morphology with dual spinosum microstructure (DSM) sensor was constructed by using clay and sucrose double template method. Benefiting from the reconfigurable behavior of the DSM, the assembled piezoresistive sensor demonstrated high sensitivity (32.9 kPa−1), pressure detection limit of 11 Pa, short response time (＜400 ms), and excellent stability (loading/unloading test of 3000 cycles). In practical application, the sensor showed excellent sensing performance in differentiating tiny stress changes and monitoring human motion in all directions, such as respiration, pulse, bending motions and gestures. Additionally, the novel sensor can detect environmental temperatures and recognize textures, which showed promising applications in intelligent electronic skins and human health monitoring. [ABSTRACT FROM AUTHOR]

Actuators based on thermotropic liquid crystal elastomers (LCEs) with excellent reversible deformations have broad applications in soft robotics, micro and nano devices, and bionic manufacturing. However, these components suffer from sharp mechanical properties degradation at phase transition temperatures. Herein, the breaking strength of the LCE at the anisotropic–isotropic transition temperature (T ni = 53.8 ℃) is increased, by an order of magnitude, by introducing a high-temperature resistant, high modulus, and self-healing crosslinked polyurethane network designed for the molecular chain network of the actuator. The developed actuator can lift an object 800 times its own weight with a contraction ratio of 40.6 %, and the object can be lifted up to 2000 times. The actuation performance was stable during the reciprocating test, and the damaged actuator could still restore 88.7 % of actuation performance and 60.4 % of the mechanical property after self-healing. Furthermore, a self-sensing characteristic was conferred by the carbon nanotube/carbon black composites (CNT/CB)-modified porous structure constructed on the surface. The actuator developed with a low actuation temperature, excellent actuation performance, self-healing, and self-sensing is expected to expand the applications of LCEs. [Display omitted] • High-strength interpenetrating polyurethane-LCEs actuators was proposed. • The breaking strength at T ni (53.8 ℃) is increased by an order of magnitude. • The damaged actuator restore 88.7 % of actuation performance after self-healing. • The actuator has the characteristic of self-sensing. [ABSTRACT FROM AUTHOR]

Abstract: The possibility of atomic scale mass delivery by bend kink in single walled carbon nanotube was investigated with the aid of molecular dynamics simulation. By keeping the bending angle while moving the tube end, the encapsulated atomic scale mass such as atom, molecule and atom group were successfully delivered through the nanotube. The van der Waals interaction between the encapsulated mass and the tube wall provided the driving force for the delivery. There were no dramatic changes in the van der Waals interaction, and a smooth and steady delivery was achieved when constant loading rate was applied. The influence of temperature on the atom group delivery was also analyzed. It is found raising temperature is harmful to the smooth movement of the atom group. However, the delivery rate can be promoted under higher temperature when the atom group is situated before the kink during the delivery. [Copyright &y& Elsevier]