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[Display omitted] To cope with the demand of more complex and variable applications, it is urgent to develop dual-mode triggered, breathable, and shape-memory wearable heaters for all-weather personal thermal management of composite phase change materials (PCMs). Herein, after high-temperature carbonization of ZnCo-MOF (metal–organic framework) nanosheet array grown in situ on flexible and breathable carbon cloth (CC) and subsequent encapsulation of polyethylene glycol (PEG), the as-prepared PEG/CC@Co/CNT (carbon nanotube) composite PCMs exhibited good breathability, mechanical strength (tensile strength of 9.15 MPa), thermal energy storage density (114.19 J/g), and shape memory due to the synergy of flexible CC skeleton and rigid PEG. More importantly, composite PCMs possessed excellent solar-thermal (93.7 %, 100 mW/cm2) and electro-thermals (94.5 %, 2.0 V) conversion and storage capacity, benefiting from the conjugation effect of high graphitized carbon/carbon heterostructure with fast electron/photon/phonon transmission and the localized surface plasmon resonance effect of Co nanoparticles. Therefore, the integration of solar heating and Joule heating into breathable composite PCMs can be accurately used for next-generation all-weather, all-season, dual-mode triggered personal thermal management, including indoor/outdoor, daytime/night, rainy/cloudy and other complex and changeable scenarios. [ABSTRACT FROM AUTHOR]

A well-dispersed Ni nano electrocatalyst boosts the kinetics and decreases the reaction overpotential of Li 2 S 4 reduction, providing more spaces for the concentration difference overpotential and allowing more soluble polysulfide intermediates farther away (l 2) from the surface of conductive materials to be reduced based on Fick's first law, significantly improving the sulfur utilization. Consequently, excellent rate performance, high areal capacity, and stable cycle performance are exhibited. [Display omitted] The lithium-sulfur battery (Li-S) has been considered a promising energy storage system, however, in the practical application of Li-S batteries, considerable challenges remain. One challenge is the low kinetics involved in the conversion of Li 2 S 4 to Li 2 S. Here, we reveal that highly dispersed Ni nanoparticles play a unique role in the reduction of Li 2 S 4. Ni-porous carbon (Ni-PC) decorated in situ on a free-standing carbon nanotube sponge (CNTS/Ni-PC) enriches the current response of liquid phase Li 2 S 4 and Li 2 S 2 around the cathode more than 8.1 and 5.7 times higher than that of the CNTS blank sample, respectively, greatly boosting the kinetics and decreasing the reaction overpotential of Li 2 S 4 reduction (lower Tafel slope and larger current response). Thus, with the same total overpotential, more space is provided for the concentration difference overpotential, allowing the more soluble polysulfide intermediates farther away from the surface of the conductive materials to be reduced based on the "wane and wax" strategy, and significantly improving the sulfur utilization. Consequently, S@CNTS/Ni-PC delivers excellent rate performance (812.4 mAh·g−1 at 2C) and a remarkable areal capacity of 10.1 mAh·cm−2. This work provides a viable strategy for designing a target catalyst to enhance the conversion kinetics in the Li 2 S 4 reduction process. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are one of the most promising energy storage systems, in which the severe shuttle effect causes the loss of the sulfur active species and unacceptable capacity and cycling stability. Here, a self-supporting functional carbon nanotube sponge (FCNTS), electrostatically repelling polysulfide anions and allowing Li+ to pass through, is synthesized by etching channels and introducing enriched anions on CNTs based on the "Donnan effect". The experimental results confirmed that FCNTS accelerated the Li-ion transport, that is, the Li+ transfer rates of the FCNTS materials were 8.226 (Li 2 S 4 reduction) and 3.627 times (Li 2 S oxidation) that of the CNTs blank samples, respectively. Meanwhile, defects and O-group modified FCNTS regulated the local charge density of carbon-based materials, which enriched the reduction current response of the soluble Li 2 S 4 and the oxidation current of Li 2 S 2 /Li 2 S around the cathode more than 1.9 and 1.6 times that of the CNTs blank samples, respectively. This significantly improved the kinetics and suppressed the overpotential. Thus, the cells assembled by S@FCNTS achieved a high-rate performance (866.9 mAh∙g−1 at 2 C), excellent stability (fading rate of only 0.035% per cycle after 500 cycles at 2 C), and a high area capacity of 13.2 mAh∙cm−2 at a high sulfur load of 10.9 mA∙cm−2. This work demonstrates a dynamic polysulfide-interception strategy to facilitate the utilization of polysulfides and provides a promising idea for the design of multi-functional sulfur storage electrode materials for high-load LSBs. [Display omitted] • A self-supporting functional CNT sponge (FCNTS) is synthesized. • FCNTS electrostatically repels polysulfide ions and allows the Li+ traverse. • Synergistic effect of defects and O-doping induces the charge rearrangement. • S@FCNTS achieves ultrafast ion transport capability along with ultrahigh capacity. [ABSTRACT FROM AUTHOR]