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[Display omitted] • Bulk nanostructured ceramic was prepared by embedding CNTs in YSZ-MgO nanocrystals. • He ion irradiation response of CNT-reinforced ceramic at 500 °C was studied. • Management of defects/He atoms via constructed ternary nanostructures was realized. • High ability in keeping microstructure stability and resisting radiation hardening. Developing long-lifetime bulk-form ceramic-based materials with high irradiation resistance is crucial for advanced nuclear systems. Here, we incorporated carbon nanotubes (CNTs) into yttria-stabilized zirconia (YSZ) and magnesia (MgO) nanocrystals to fabricate bulk YSZ-MgO-CNT nanocomposites with abundant ternary nanostructures by spark plasma sintering. To understand the role of tailored ternary nanostructure on irradiation, we investigated the microstructure and mechanical properties evolutions of the YSZ-MgO-CNT nanocomposites irradiated by multi-energy He+ ions at high temperature to different fluences. Compared with the single-phase YSZ and ultrafine-grained YSZ-MgO composites, the YSZ-MgO-CNT nanocomposites possessed higher ability to manage irradiation-induced He bubbles/defects via the defect-interface interactions of proposed "loading-unloading" and "loading-transporting-unloading" mechanisms for controlling the dynamical behaviors of He atoms/defects in the CNT-doped ternary nanostructures, thereby presenting more stable microstructure and better performance in resisting irradiation hardening. This work provides insight into the design of advanced inert matrix nuclear fuel and new nuclear waste management materials. [ABSTRACT FROM AUTHOR]

Friction and wear are omnipresent, which have caused many problems such as energy dissipation and component damage, making all mankind face an energy crisis and huge economic losses. The prosperity of carbon materials in the past two decades has provided us with a versatile platform for various prominent usages like energy, electronics, and biology. At present, applications of advanced carbon materials, such as carbon nanotubes, graphite, fullerene, graphene and nanodiamonds have inaugurated a new epoch of tribology. But, fundamental tribological understandings of carbon materials, as well as their relations to polymer, metal and ceramic matrices, remain fully unexplored. Herein, this review summarizes the up-to-date advances on carbon materials for realizing superior anti-friction and wear-resistance performances in the polymer/metal/ceramic systems form micro to macro. Finally, we point out the condensed conclusions, foreseeable challenges associated with carbon materials, and potential outlooks and future recommendations of such tribological field. [ABSTRACT FROM AUTHOR]

Efficient toughening of the interlaminar fracture toughness for CFRP composites without sacrificing in-plane mechanical performance remained an unresolved challenge. Here, we present a synergistic toughening strategy by construction of hierarchical architecture, within which carbon nanotubes (CNTs) in-depth stitched into the nano-channel between neighboring carbon fibers at the interlaminar region. Mode I fracture test revealed that, even at low concentration of CNTs (0.3 wt%), a considerable improvement (50%) on mode I fracture energy G I c of composites can be realized, from 1098.6 to 1647.8 J/m 2 which is nearly two times greater than that of most aerospace CFRP laminates (∼ 500 J/m 2). The excellent fracture toughness is predominantly attributed to the desired hierarchical architecture, which simultaneously triggered the intrinsic toughening by CNTs nano-bridging and extrinsic toughening mechanisms due to carbon fiber bridging, as was demonstrated by SEM images of fracture surfaces and further verified by finite element simulations. These findings offer significant guidelines for designing CFRP composites with high fracture toughness by application of low content CNTs using cost-effective resin mixing process. [Display omitted] • A desirable hierarchical architecture for CFRP was constructed. • High interlaminar fracture toughness is achieved with small amount of additional CNTs. • CNTs are able to trigger extrinsic toughening mechanism in the form of carbon fiber bridging. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interaction mechanism between ions and carbon nanotubes was studied theoretically, and a novel PU/EMIM:TFSI gel with excellent ion transport ability was prepared. • Based on the PU/EMIM:TFSI gel, a multilayer infrared camouflage device was developed, whose regulation coefficient reaches 0.85. • The infrared camouflage devices were further integrated into an array device with 4 rows and 4 columns, and a wireless control system was constructed to realize remote intelligent infrared camouflage. The dynamic regulation of infrared signals has received widespread attention. For the typical multilayer adaptive infrared camouflage structure, many efforts have been made to explore a variety of materials; metals, carbon nanomaterials and polymers can all be used in this field. However, little attention has been given to the mechanism of mass transfer within the structure, which could play a decisive role in the infrared camouflage performance. In this paper, the influence of cation and anion enrichment on the band structure and density of states of multiwalled carbon nanotubes (MWCNTs) is discussed through density functional theory (DFT), and the results show that ion migration plays an important role in the regulation of the emissivity. On the basis of theoretical research, a novel waterborne polyurethane (WPU)/ionic liquid (IL) gel is further prepared to realize control of the ionic transport capability, and a MWCNT film-based sandwich structure is fabricated to achieve adaptive infrared camouflage. The maximum emissivity regulation coefficient reaches 0.85, which is the highest to the best of our knowledge. The optimization scheme proposed in this work can provide a good reference for other similar problems. [ABSTRACT FROM AUTHOR]

For graphene-based film, versatility is essential for its potential multi-functional applications. In order to obtain graphene-based films with superior mechanical and electrical properties, a "brick and mortar" structure has been proposed by previous researchers. In this structure, the graphene or reduced graphene oxide (rGO) layers are the "bricks", while the "mortar" is various, which is critical to the performance of the films. In this work, the mixture of carbon nanotube (CNT)/polyurethane (PU) was introduced as the mortar to bind rGO layers, forming a dense layered film. The PU builds strong interactions between rGO layers through covalent bonds, while the CNTs help to highly reduce the inter-layer electrical resistance. Hence, the CNT/PU/rGO film shows an optimized tensile strength of 1193 MPa and an electrical conductivity of 687 S cm−1. More remarkably, the PU has good compatibility with ionic liquid (IL), and can build internal transport tunnels for IL in the films. IL was further introduced into the composite film. By applying voltage upon the two sides of the film, ion transport across the two sides of the film can be fast and precisely guided. The interaction between IL and the nano-carbon assemblies can tune the infrared emissivity of the composite film, which "function" proposes the film for potential application as a flexible infrared camouflage device. The performance of the infrared camouflage film is investigated in this work. [ABSTRACT FROM AUTHOR]