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Rechargeable lithium metal batteries are next generation energy storage devices with high energy density, but face challenges in achieving high energy density, high safety, and long cycle life. Here, lithium metal batteries in a novel nonflammable ionic‐liquid (IL) electrolyte composed of 1‐ethyl‐3‐methylimidazolium (EMIm) cations and high‐concentration bis(fluorosulfonyl)imide (FSI) anions, with sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) as a key additive are reported. The Na ion participates in the formation of hybrid passivation interphases and contributes to dendrite‐free Li deposition and reversible cathode electrochemistry. The electrolyte of low viscosity allows practically useful cathode mass loading up to ≈16 mg cm−2. Li anodes paired with lithium cobalt oxide (LiCoO2) and lithium nickel cobalt manganese oxide (LiNi0.8Co0.1Mn0.1O2, NCM 811) cathodes exhibit 99.6–99.9% Coulombic efficiencies, high discharge voltages up to 4.4 V, high specific capacity and energy density up to ≈199 mAh g−1 and ≈765 Wh kg−1 respectively, with impressive cycling performances over up to 1200 cycles. Highly stable passivation interphases formed on both electrodes in the novel IL electrolyte are the key to highly reversible lithium metal batteries, especially for Li–NMC 811 full batteries.

Fatigue resistance is a key property of the service lifetime of structural materials. Carbon nanotubes (CNTs) are one of the strongest materials ever discovered, but measuring their fatigue resistance is a challenge because of their size and the lack of effective measurement methods for such small samples. We developed a noncontact acoustic resonance test system for investigating the fatigue behavior of centimeter-long individual CNTs. We found that CNTs have excellent fatigue resistance, which is dependent on temperature, and that the time to fatigue fracture of CNTs is dominated by the time to creation of the first defect.

Consistent-chirality carbon nanotube tangles with high on-currents in transistors.

Energy storage in a proper form is an important way to meet the fast increase in the demand for energy. Among the strategies for storing energy, storage of mechanical energy via suitable media is widely utilized by human beings. With a tensile strength over 100 GPa, and a Young's modulus over 1 TPa, carbon nanotubes (CNTs) are considered as one of the strongest materials ever found and exhibit overwhelming advantages for storing mechanical energy. For example, the tensile‐strain energy density of CNTs is as high as 1125 Wh kg‐1. In addition, CNTs also exhibit great potential for fabricating flywheels to store kinetic energy with both high energy density (8571 Wh kg‐1) and high power density (2 MW kg‐1 to 2 GW kg‐1). Here, an overview of some typical mechanical‐energy‐storage systems and materials is given. Then, theoretical and experimental studies on the mechanical properties of CNTs and CNT assemblies are introduced. Afterward, the strategies for utilizing CNTs to store mechanical energy are discussed. In addition, macroscale production of CNTs is summarized. Finally, future trends and prospects in the development of CNTs used as mechanical‐energy‐storage materials are presented.

Poly(ester amide) has attracted much attention because they demonstrate satisfactory mechanical performance, yet are biodegradable. Owing to the increasing depletion of fossil resources, we chose 1,4‐butanediol, 1,10‐decanediamine (DD), 1,10‐sebacic acid, and itaconic acid (IA), which can be produced in large scale by fermentation of renewable resources, to synthesize a series of biobased poly(ester amide)s (BPEAs) by condensation polymerization. We used multiple monomers to suppress crystallization. The pyrrolidone rings formed between DD and IA increases the molecular spacing and the chain irregularity of BPEAs. The properties of BPEAs were tunable by adjusting the monomer ratio. The effect of DD content on the molecular weight, thermal stability, mechanical properties, and in vitro degradation of BPEAs was investigated. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43446.

Carbon nanotubes (CNTs) possess a unique tubular structure composed of highly graphitized atoms. Since their sp2 hybridized skeleton is discovered under the microscope, extensive attention is paid to their peculiar physics and extraordinary performances in mechanics, optics, and electricity. However, due to the challenges in controlled synthesis and mass production, there is a long bottleneck period in both the science and engineering of CNTs. In the recent decade, significant advances have emerged in ton‐scale production, 3D microprocessors, ultrastrong fibers, etc., which have pushed the renaissance of CNTs toward a new peak. This important progress benefits from the critical but commonly ignored breakthroughs in the precise structure control and assembly of CNTs. Herein, the morphological manipulation and technical routes toward the CNT industry will be focused on. First, the growth mechanism of defect‐free aligned CNTs will be discussed. Subsequently, nondestructive flow‐guided fabrication methods and their application paradigms are summarized. Then, attention will be turned to assembly‐based industrial production and applications of CNTs. Some research prospects toward the precise synthesis and CNT industry are proposed at last, in the hope of building a comprehensive understanding on the catalytic assembly toward defect‐free nanostructures and their high‐end applications.

Chirality is a significant structural feature for chemistry, biology, physics, and materials science, and especially determines the electrical, mechanical, and optical properties of diverse tubular structures, such as carbon nanotubes (CNTs). To recognize the chirality of nanotubes, templates are introduced as potential tools to obtain crystalline samples with visible chiral fringes under electron microscopes. However, few efforts show optimistic results, and new understanding is desired to control the sample quality with CNT templates. Here, a synthesis strategy of single-crystalline molybdenum trioxide (α-MoO ) nanotubes (MONTs) on CNT surfaces is reported to build a 1D van der Waals (vdW) heterostructure. The chirality of the MONTs can be directly "seen" and their structural selectivity is revealed. First, the centralized distribution of the chiral angles of the MONTs indicates a preferential orientation due to the anisotropic bending rigidity of the 2D layers. Then, the interlayer mismatching rejects the radial stacking of α-MoO to maintain the single-walled nature. These results provide a spontaneous strategy for the efficient recognition and control of chirality, and open up a new avenue for CNT-based functional 1D vdW heterostructures.