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Efficient heat transfer control is highly demanded for dynamic thermal management of equipment and buildings especially when the environmental temperature dramatically changes. Thermal switches, the current approach of heat transfer control, suffer from the issues of low switching ratios below eight and sharp state transition between "on" and "off". Herein, a continuously‐tuned thermal regulator with an ultrahigh thermal‐conductivity change ratio of 43 based on superaligned carbon nanotube aerogel is reported, which works on the regulation of both thermal interfacial resistance and conduction pathways by compressive deformation‐induced microstructure evolution. This thermal regulator can stabilize the device temperature at 25 °C when the environmental temperature varies by 7 and 11 °C under the natural convection and forced convection conditions, respectively. Toward practical application, the thermal regulator with flexibility is wrapped around a cylindrical lithium‐ion battery to control the operation temperature within the optimal range of 20–40 °C for enhanced discharging performance even at an environmental temperature of −20 °C. Besides, by combining the thermal regulator with radiative cooling film, the house model temperature can be lowered by 2.7 °C during daytime and raised by 1.1 °C during nighttime compared with the bare one. This efficient thermal regulation approach offers an effective solution for practical thermal management. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries (LIBs) have gained widespread attention due to their numerous advantages, including high energy density, prolonged cycle life, and environmental friendliness. Nevertheless, their electrochemical performance deteriorates rapidly under extreme temperature conditions, accompanied by a series of safety issues. Electrolyte optimization has emerged as a crucial and feasible strategy to expand the operational temperature range of LIBs. This review comprehensively summarizes the challenges, advances, and characterization methodologies of electrolytes at both subzero and elevated temperatures. Initially, it discusses the degradation mechanisms of different types of electrolytes at extreme temperatures, integrates recent advances, and offers insights into future research directions. Subsequently, various experimental techniques are systematically presented to evaluate the fundamental physical properties, stability, and dynamic behaviors of electrolytes in non‐ambient environments. Finally, it also provides relevant computational methods across the electronic, molecular, and macroscopic scales, and explores the application of high‐throughput techniques in this field. This review offers valuable guidance for breaking the working temperature limits of electrolytes and promoting the development of next‐generation LIBs. [ABSTRACT FROM AUTHOR]

The polysulfide (PS) dissolution and low conductivity of lithium sulfides (Li2S) are generally considered the main reasons for limiting the reversible capacity of the lithium‐sulfur (Li‐S) system. However, as the inevitable intermediate between PSs and Li2S, lithium disulfide (Li2S2) evolutions are always overlooked. Herein, Li2S2 evolutions are monitored from the operando measurements on the pouch cell level. Results indicate that Li2S2 undergoes slow electrochemical reduction and chemical disproportionation simultaneously during the discharging process, leading to further PS dissolution and Li2S generation without capacity contribution. Compared with the fully oxidized Li2S, Li2S2 still residues at the end of the charging state. Therefore, instead of the considered Li2S and PSs, slow electrochemical conversions and side chemical reactions of Li2S2 are the determining factors in limiting the sulfur utilization, corresponding to the poor reversible capacity of Li‐S batteries. [ABSTRACT FROM AUTHOR]

Non‐dispersive infrared (NDIR) gas monitoring has advantages of environment stability, convenient operation and maintenance, wide detection range, and multi‐gas‐detection capability. However, the conventional IR sources for NDIR gas monitoring, such as miniature lamps, microelectromechanical system (MEMS) light sources, and light‐emitting diodes (LEDs), can only work at narrow modulation frequency and spectral range, or require complicated design and fabrication, because of the constraint of materials and work principle. These issues cause low data acquisition rate, poor anti‐interference ability and limited gas compatibility to NDIR. Here, the super‐aligned carbon nanotube (SACNT) film is developed as an IR source in NDIR gas monitoring system. It has a wide spectral range (0.2–334 µm), a facile fabrication method, and can work up to a high frequency ≈150 kHz. A mechanical‐chopper‐free and wide‐concentration‐range monitoring equipment for CO2 and CH4 greenhouse gases is demonstrated with SACNT film IR source. The concentration ranges for CO2 and CH4 investigated in this paper are 0.0195–20.10% (v/v) and 0.10–17.11% (v/v), respectively. It can be easily applied to monitor other kinds of gases as well. [ABSTRACT FROM AUTHOR]

As the semiconductor industry enters the post‐Moore era, reconfigurability on the device level, that incorporates multifunction in a device unit to realize more complex systems with more compact logic gates, is a promising methodology to extend the development of integrated circuit industry. Here, a reconfigurable carbon nanotube (CNT) barristor is developed on the basis of a Schottky barrier (SB) CNT transistor. The device shows a significant rectifying characteristic and can be reconfigured to a forward rectifying mode or a backward rectifying mode by applying an appropriate gate voltage. The reconfigurability originates from the ambipolar characteristics of the CNT channel, and the rectification behaviors can be attributed to the drain‐induced self‐gating effect. Additional experiments reveal that it is the interfacial charge redistribution that plays the role of an additional gate on the SB near the drain. A gate‐controllable half‐wave rectifier has been fabricated by using the reconfigurable CNT barristor. The CNT barristor brings new functions to CNT electronic devices and also opens up a new methodology for future reconfigurable device design. [ABSTRACT FROM AUTHOR]

Recently, advanced flexible tactile sensors have been widely studied for human motion detection, which is an essential part of human healthcare monitoring. New types of materials with novel composition and structures play a significant role in sensing performance improvement. Herein, a stretchable and dissolvable porous silver nanowire (Ag NW)/polyvinyl alcohol (PVA) nanocomposite hydrogel is fabricated through a facile foaming and freezing‐thawing combined approach. The PVA gel is foamed with lots of tailorable micropores to achieve much enhanced stretchability and compressibility. Ag NWs are uniformly embedded inside PVA matrix to increase the permittivity upon introduction of numerous microcapacitors. Incorporated with carbon nanotube network electrodes, a capacitive tactile sensor is developed with high sensitivity (1.9 kPa−1), wide detection range (250 kPa), quick response time (25 ms), and remarkable stability over 10 000 loading/unloading cycles. Wearable sensing demonstration of detecting various human motions is performed. The hydrogel‐based sensor can be dissolved in hot water within minutes with recycling use of electrode material, which is environmentally friendly. A large‐area integrated sensor sheet can be made upon one fabrication process followed by cut into small sensor devices with desired shapes, indicating potential customized mass production. The proposed microporous nanocomposite hydrogel‐based sensor is promising in wearable sensing applications. [ABSTRACT FROM AUTHOR]

Cross‐linked polyethylene glycol‐based resin (c‐PEGR) is constructed by a ring‐opening reaction of polyethylene glycol diglycidyl ether (PEGDE) with epoxy groups and polyether amine (PEA) with amino groups. By confining the hydroxyl groups with inferior oxidative stability to the c‐PEGR backbone, the oxidation potential of the PEG‐based polymer material with reduced reactivity is boosted to 4.36 V. The c‐PEGR based gel electrolyte shows excellent flexibility, lithium‐ion transport, lithium compatibility, and enhanced oxidation stability, and is successfully applied to a 4.35 V lithium cobaltate (LCO)||lithium (Li) battery system. A quasi‐static linear scanning voltammetry (QS‐LSV) method is proposed for the first time to accurately measure the oxidation potential and electrochemical stability window of materials with low conductivities such as polymers, which possesses the advantages of high accuracy and short test time. This work provides new insights and research techniques for selecting polymer electrolytes for high‐voltage flexible lithium‐ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur (Li/S) cells. A comprehensive understanding of the shuttle‐related sulfur speciation and diffusion process is vital for addressing this issue. Herein, we employed in situ/operando X‐ray absorption spectroscopy (XAS) to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte‐separator and electrolyte‐anode interfaces, respectively, in a real‐time condition. After we adopted a shuttle‐suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix (BSOC), we found the Li/S cell showed greatly improved sulfur utilization and longer life span. The operando S K‐edge XAS results revealed that the BSOC modification was bi‐functional: trapping polysulfides and catalyzing conversion of sulfur species simultaneously. We elucidated that the polysulfide trapping‐and‐catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection. Our results could offer potential stratagem for designing more advanced Li/S cells. [ABSTRACT FROM AUTHOR]

The transport property of six types of individual carbon nanotubes (CNT) with specified chiral indices at high temperature is investigated on a home‐made apparatus. It is found that the resistivity of all individual CNTs increases with temperature monotonically, whereas the mobility decreases with temperature and follows different laws in different temperature ranges. The carrier concentration increases exponentially with −1/T. The mobility of CNT deviates from traditional trends with temperature, T−β, at high temperature (1070–1728 K). This deviation is attributed to scattering with optical phonons at high temperature. The data show that the electron‐optical phonon interaction becomes dominant in the temperature range of 1070–1362 K for all measured CNTs. Finally, result within a polaron model is discussed. [ABSTRACT FROM AUTHOR]

High‐temperature thermionic electron emission from different types of individual suspended carbon nanotubes (CNTs) in a homemade chip is studied. When collecting emission electrons with an external electrode, it is found that the collecting electric field influence the transport current in the CNTs, and the thermionic electron emission deviated from the traditional thermionic electron emission model and cannot reach "saturation". This effect is analyzed for single‐walled, double‐walled, multiwalled‐CNT and CNT bundles. It is found that this effect show correlation with the conductivity and diameter of the CNT. With the increase in metallicity, the influence of collecting electrode is gradually weakened. Also, the effect shows a negative correlation with the diameter of CNTs. An equation is proposed to describe the measured thermionic emission curve and determine the "effective" work function of the CNT. [ABSTRACT FROM AUTHOR]

Current artificial tactile sensors mostly exploit a variety of electron‐related physical mechanisms to obtain high sensitivity and low detection force. However, these mechanisms are still distinct from the ion‐related biological processes of human's tactile sensation, and are therefore away from the goal of bionic applications. In the past few years, only several types of ionic tactile sensors have been proposed, and they are still subject to low sensitivity. Here, a novel type of ultrasensitive hydrogel tactile sensor is reported based on asymmetric ionic charge injection as the working mechanism, named as asymmetric ionic sensing hydrogel (AISH). With a small external working voltage of only tens of millivolts, these AISH devices show an extremely low detection force of 0.075 Pa, ultrahigh sensitivity of 57–171 kPa−1, and excellent cycling reliability upon pressing. Applications of these ultrasensitive tactile sensors in fingerprint identification of voice, monitoring of pulse waves, and detection of underwater wave signals are experimentally demonstrated. Combining the merits of simple fabrication process, ionic‐type detection mechanism, and ion injection procedure, such AISH sensors not only reveal a new strategy toward highly sensitive tactile sensors, but also show realistic potential applications in future wearable electronic and bioelectronic devices. [ABSTRACT FROM AUTHOR]

As a domestic waste in daily life, eggshell membrane (ESM) is a unique biomaterial due to its biocompatibility, bioadsorption, and the structure of interwoven and coalescing fibers with many pores which can be utilized in many fields. Herein, a new kind of potentially biocompatible energy harvesting and storage device based on polymer polyaniline/carbon nanotube (PANI/CNT) composite electrodes and ESM is designed. Without external electric power, a single device can extract a maximal output voltage of 0.26 V from water osmosis. The energy can be stored directly and released circularly, and the output voltage can achieve superposition by integrating devices in series. This self‐charging bioelectric phenomenon can be explained by the membrane potential of the ESM induced by water movement. Due to the biocompatible feature of the ESM, and sufficiently high electric output, this study provides a new idea for sustainable and biocompatible energy harvesting and storage devices. [ABSTRACT FROM AUTHOR]

Ultrathin MnO2/graphene oxide/carbon nanotube (G/M@CNT) interlayers are developed as efficient polysulfide-trapping shields for high-performance Li-S batteries. A simple layer-by-layer procedure is used to construct a sandwiched vein-membrane interlayer of thickness 2 µm and areal density 0.104 mg cm−2 by loading MnO2 nanoparticles and graphene oxide (GO) sheets on superaligned carbon nanotube films. The G/M@CNT interlayer provides a physical shield against both polysulfide shuttling and chemical adsorption of polysulfides by MnO2 nanoparticles and GO sheets. The synergetic effect of the G/M@CNT interlayer enables the production of Li-S cells with high sulfur loadings (60-80 wt%), a low capacity decay rate (−0.029% per cycle over 2500 cycles at 1 C), high rate performance (747 mA h g−1 at a charge rate of 10 C), and a low self-discharge rate with high capacity retention (93.0% after 20 d rest). Electrochemical impedance spectroscopy, cyclic voltammetry, and scanning electron microscopy observations of the Li anodes after cycling confirm the polysulfide-trapping ability of the G/M@CNT interlayer and show its potential in developing high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

Large current hysteresis is observed in carbon nanotube (CNT) transistors and usually shows as a positive threshold voltage shift when the gate sweeping direction changes from positive to negative. This paper reports fabrication of inverse hysteresis CNT thin‐film transistors (TFTs) using magnetron sputtered oxide as a dielectric. Stacking of the sputtered dielectric with dielectrics deposited by other methods, such as atomic layer deposition, can effectively reduce or even eliminate the hysteresis. This can be explained as a combination of the effects of surface and interface trapped charges. Additionally, this hysteresis reduction method is widely compatible with various CNT‐TFT structures and types and is even suitable for MoS2 TFTs. The output characteristics and frequency responses of large and small hysteresis devices are compared and show that the small‐hysteresis inverter has lower distortion, and that its maximum operating frequency is nearly five times larger than that of TFTs with normal hysteresis. [ABSTRACT FROM AUTHOR]

Recently, actuating materials based on carbon nanotubes or graphene have been widely studied. However, present carbon-based actuating materials are mostly driven by a single stimulus (humidity, light, electricity, etc.), respectively, which means that the application conditions are limited. Here, a new kind of multiresponsive actuating material which can be driven by humidity, light, and electricity is proposed, so it can be used in various conditions. The fabrication is based on the simplest pencil-on-paper method, in which the pencil and paper are both low-cost and easily obtained daily materials. The actuation effect is more remarkable due to a dual-mode actuation mechanism, which leads to an ultralarge actuation (bending curvature up to 2.6 cm−1). Elaborately designed, the actuator can further exhibit a bidirectional bending actuation, which is a significant improvement compared with previous reported thermal actuators. What is more, a colorful biomimetic flower and a smart curtain are also fabricated, fully utilizing the printable characteristic of the paper and multiresponsive characteristic of the actuator. It is assumed that the newly designed actuating material has great potential in the fields of lab-on-paper devices, artificial muscles, robotics, biomimics, and smart household materials. [ABSTRACT FROM AUTHOR]

Ultralong cycle‐life and stable Li2S‐C/Li cells can be achieved by using highly nitridated graphene and controlling both recharge capacity and voltage. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) current collectors with excellent flexibility, extremely low density (0.04 mg cm−2), and tunable thickness are fabricated by cross-stacking continuous CNT films drawn from super-aligned CNT arrays. Compared with metal current collectors, better wetting, stronger adhesion, greater mechanical durability, and lower contact resistance are demonstrated at the electrode/CNT interface. Electrodes with CNT current collectors show improvements in cycling stability, rate capability, and gravimetric energy density over those with metal current collectors. These results suggest that CNT films can function as a promising type of current collector for lightweight and flexible lithium ion batteries with high energy density. [ABSTRACT FROM AUTHOR]

Ionic Sensing Hydrogels: Ultrasensitive, Low-Voltage Operational, and Asymmetric Ionic Sensing Hydrogel for Multipurpose Applications (Adv. Funct. In article number 1909616, Lei Zhang, Kai Liu, and co-workers present a hydrogel-based tactile sensor with an extremely low detection limit (0.075 Pa) that employs a novel asymmetric ionic injection mechanism. The application of these ultrasensitive tactile sensors in fingerprint identification of voices, monitoring of pulse waves, and detection of underwater wave signals is experimentally demonstrated. [Extracted from the article]

Carbon nanotubes (CNTs) with the advantage of high thermal conductivity and light weight can be widely used in thermal management. Meanwhile, heat removal for hot spots has become a major issue in the development of electronics because of the increasing of power density and thermal load. Therefore, more effective heat dissipation approaches are needed. Here, the high water‐absorbent and phase‐change heat dissipation materials based on super‐aligned cross‐stack CNT (CSCNT) films with excellent cooling performance are reported. Pure CSCNT and CaCl2/CSCNT composite show the outstanding water absorption property because of their high specific surface area and porosity. Combined the high natural convection and heat radiation of CSCNTs with heat removal by water evaporation, the heat dissipation coefficient of CaCl2/CSCNT can reach as high as 98 W m−2 K−1 with the help of auxiliary plate. Due to the high absorption rate, the composite can absorb water when electronics are at low power and dissipate heat by water evaporation at high power. Moreover, it is founded that there is a dynamic balance of water absorption and desorption to enhance cooling performance at thermal equilibrium. [ABSTRACT FROM AUTHOR]

Most of conventional actuators have only actuation functions, lacking in real‐time sensing signal feedback. In article number 1806057, Luzhuo Chen and co‐workers report a graphene‐based actuator with integrated‐sensing functions. The robot hand based on the actuator can not only manipulate an object, but also sense every actuation state. This work will open new application fields in integrated‐multifunctional devices. [ABSTRACT FROM AUTHOR]

Flexible actuators have important applications in artificial muscles, robotics, optical devices, and so on. However, most of the conventional actuators have only actuation function, lacking in real‐time sensing signal feedbacks. Here, to break the limitation and add functionality in conventional actuators, a graphene‐based actuator with integrated‐sensing function is reported, which avoids the dependence on image post‐processing for actuation detection and realizes real‐time measurement of the shape‐deformation amplitudes of the actuator. The actuator is able to show a large bending actuation (curvature of 1.1 cm−1) based on a dual‐mode actuation mechanism when it is driven by near infrared light. Meanwhile, the relative resistance change of the actuator is −17.5%. The sensing function is attributed to piezoresistivity and thermoresistivity of the reduced graphene oxide and paper composite. This actuator can be used as a strain sensor to monitor human motions. A smart gripper based on the actuators demonstrates perfect integration of the actuating and sensing functions, which can not only grasp and release an object, but also sense every actuation state of the actuator. The developed integrated‐sensing actuator is hopeful to open new application fields in soft robotics, artificial muscles, flexible wearable devices, and other integrated‐multifunctional devices. A graphene‐based actuator with integrated‐sensing function is developed. It realizes real‐time measurements of the shape deformation of the actuator. A smart gripper based on the actuator demonstrates perfect integration of actuating and sensing functions. It can not only grasp and release an object, but also sense every actuation state of the actuator. [ABSTRACT FROM AUTHOR]

A multi‐responsive actuator based on paper and polymer composite is fabricated by a Pencil‐on‐Paper method, which is described by L. Chen, W. Zhang, C. Liu, and co‐workers on page 7244. A colorful biomimetic flower and a smart curtain are also fabricated to demonstrate the applications. This work has great potential in the fields of lab‐on‐paper devices, artificial muscles, robotics, and biomimics. [ABSTRACT FROM AUTHOR]

On page 846, Jiaping Wang and co‐workers report carbon nanotube (CNT) current collectors for lithium ion batteries (LIBs). The CNT current collectors with excellent flexibility, extremely low density, and tunable thickness are fabricated by cross‐stacking continuous CNT films drawn from super‐aligned CNT arrays. Electrodes with CNT current collectors show better wetting, stronger adhesion, lower contact resistance, greater mechanical durability, and higher energy density than those with metal current collectors, suggesting CNT films as a promising type of current collector for lightweight and flexible LIBs. [ABSTRACT FROM AUTHOR]