We report the synthesis and characterization of (Ph 4 P) 2 SbCl 5 , a novel ionically bonded organic metal halide hybrid with a zero-dimensional (0D) structure at the molecular level. By cocrystallization of tetraphenylphosphonium (Ph 4 P + ) and antimony (Sb 3+ ) chloride salts, (Ph 4 P) 2 SbCl 5 bulk single crystals can be prepared in high yield, which exhibit a highly efficient broadband red emission peaked at 648 nm with a photoluminescence quantum efficiency (PLQE) of around 87%. Density functional theory (DFT) calculations reveal the origin of emission as phosphorescence from the excitons localized at SbCl 5 2− with strong excited-state structural distortion. Interestingly, (Ph 4 P) 2 SbCl 5 bulk crystals with a PLQE of around 100% can be prepared via a rapid crystal growth process within minutes, followed by a spontaneous structural transformation. It was found that the rapid growth process yielded a yellow emitting kinetically favored metastable product containing solvent molecules, which turned into the red emitting thermodynamically stable product slowly at room temperature or quickly upon thermal treatment.

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As an excellent candidate for lightweight structural materials and nonmetal electrical conductors, carbon nanotube reinforced carbon matrix (CNT/C) composites have potential use in technologies employed in aerospace, military, and defense endeavors, where the combinations of light weight, high strength, and excellent conductivity are required. Both polymer infiltration pyrolysis (PIP) and chemical vapor infiltration (CVI) methods have been widely studied for CNT/C composite fabrications with diverse focuses and various modifications. Progress has been reported to optimize the performance of CNT/C composites from broad aspects, including matrix densification, CNT alignment, microstructure control, and interface engineering, etc. Recent approaches, such as using resistance heating for PIP or CVI, contribute to the development of CNT/C composites. To deliver a timely and up-to-date overview of CNT/C composites, we have reviewed the most recent trends in fabrication processes, summarized the mechanical reinforcement mechanism, and discussed the electrical and thermal properties, as well as relevant case studies for high-temperature applications. Conclusions and perspectives addressing future routes for performance optimization are also presented. Hence, this review serves as a rundown of recent advances in CNT/C composites and will be a valuable resource to aid future developments in this field.

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and environmentally friendly conductive cables or wires as a replacement for copper. From this view, carbon-based nanomaterial is a potential candidate.Carbon related nanomaterials including fullerenes, carbon nanotubes (CNTs), and graphene are promising due to their exceptional conductive and electronic transport properties, which may accelerate the practical and potential applications for various kinds of novel engineering areas spanning from electronics, energy storage, and advanced materials to nanotechnology and biotechnology. Among the family of carbon nanomaterials, CNTs have been a particularly attractive material since its discovery in 1991 by Iijima, [1] due to their nanoscale 1D shape, excellent mechanical properties, tunable electrical properties either metallic or semiconducting, high current carrying capacity, and many other exciting properties. These properties have highlighted the potential of CNTs use in a plethora of applications, including electrically conductive fillers in polymer composites, flexible and transparent conductive films, microelectronics (transistors, interconnectors, heat dissipaters), and lightweight conducting wires and cables. [2] Figure 1 points out the forecast presented by Endo et al. [3] on the present, near future, and long term applications of CNTs in various fields. An interesting potential application of CNTs is the long-term electrical conductors, which are able to transmit power from plants to plants or households, as well as be used in electronic devices.Compared to conventional copper cables or wires, CNT based cables have several advantages including 1) a lower density of 1.3 g cm −3 for single-walled carbon nanotubes (SWCNTs) [4] and 2.1 g cm −3 for multiwalled carbon nanotubes (MWCNTs), [5] both of which are much lower than that of copper, 8.96 g cm −3 ; [6] 2) environmental stability, which can stand with severe conditions including high pressure, large temperature changes, etc.; 3) excellent mechanical performance with a Young's modulus and strength in the ranges of 1.0 TPa and 50 GPa, respectively; [7] 4) ultrahigh electrical conductivity as high as 10 8 S m −1 for SWCNTs, which is higher than that of copper (≈10 7 S m −1 )). [8] Furthermore, the limited amount of conventional conductive metal resources in nature and their soaring market price greatly increased the need for a desirable alternative solution that are abundant in nature, low-cost, andThe lack of progress to obtain commercially available large-scale production of continuous carbon nanotube (CNT) fibers has provided the motivation for researchers to develop high-performance bulk CNT assemblies that could more effectively transfer the superb mechanical, electrical, and other excellent properties of individual CNTs. These wire-like bulk assemblies of CNTs have demonstrated the potential for being used as electrical conductors to replace conventional conductive materials, such as copper and aluminum. CNT conductors are extremely lightweight, corrosive-resistive, and mechanically strong while being ...