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The microstructure and the electrical, thermal, and mechanical properties of bulk Ti2AlC synthesized by self‐propagating high‐temperature combustion synthesis with pseudo hot isostatic pressing (SHS/PHIP) were investigated in detail. The plate‐like Ti2AlC grains distribute irregularly, with the grain size of around 6 μm in length and 1 μm in width. With increasing temperature, the electrical resistivity increases linearly from room temperature (RT) to 900°C, but the thermal conductivity decreases slightly. The RT electrical resistivity and thermal conductivity are 0.40 ± 0.03 μΩ·m and 27.0 W·(m·K)−1, respectively. The electronic component of the thermal conductivity is the dominant mechanism at all temperatures, and the phonon contribution almost can be neglected above 873 K. With increasing temperature, the flexural strength increases first, then decreases above 550°C, at which it reaches the maximum value of 539 ± 36 MPa. The brittle‐to‐plastic transition temperature falls in the temperature range of 750°C–950°C. The Ti2AlC synthesized by SHS/PHIP process exhibits an anisotropic compressive strength. The work of fracture of Ti2AlC is estimated to be 200 ± 7 J/m2, which is much higher than that of traditional ceramics.

The rapid development of next‐generation portable electronic devices urgently requires dual‐functional materials that possess both efficient heat dissipation and outstanding electromagnetic interference (EMI) shielding performances. In this study, anisotropically oriented carbon films with high thermal conductivity and excellent EMI shielding properties are prepared through an innovative glucose hydrogel‐controllable carbonization method. The horizontal alignment of nanocrystalline graphite results in oriented structures with an extremely high in‐plane thermal conductivity of 439.9 W m−1 K−1, exhibiting a more effective heat‐dissipating capacity on smartphones than their commercial graphite counterparts. Additionally, owing to multiple internal reflections arising from the oriented structures, the films exhibit an EMI shielding effectiveness (SE) of 21.72 dB at an ultrathin thickness of 480 nm in the X‐band and an extraordinarily high absolute shielding effectiveness (SSE/t) of 275 883 dB cm2 g−1, significantly outperforming most of the reported synthetic materials. Furthermore, the flexibility, high mechanical strength, and stability of the films are demonstrated and therefore show promising application prospects. This study offers a facile yet feasible strategy for preparing dual‐functional materials to address the heat emission and EMI problems of advanced electronic devices in a more economical and environmentally friendly manner.

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Several-millimeter long SiC nanowires (NWs) with unique optical properties, excellent thermal stability and flexible nanomechanical properties were synthesized using a simple method with silicon and phenolic resin as the raw materials. The SiC NWs displayed special optical properties that were attributed to their large size and Al-doping. They displayed broad green emission at 527.8 nm (2.35 eV) and purple emission concentrated at 438.9 nm (2.83 eV), in contrast to the other results, and the synthesized SiC NWs could also remain relatively stable in air up to 1000 °C indicating excellent thermal stability. The Young’s moduli of the SiC NWs with a wide range of NW diameters (215–400 nm) were measured using an in situ nanoindentation method with a hybrid scanning electron microscopy/scanning probe microscopy (SEM/SPM) system for the first time. The results suggested that the values of the Young’s modulus of the SiC NWs showed no clear size dependence, and the corresponding Young’s moduli of the SiC NWs with diameters of 215 nm, 320 nm, and 400 nm were approximately 559.1 GPa, 540.0 GPa and 576.5 GPa, respectively. These findings provide value and guidance for studying and understanding the properties of SiC nanomaterials and for expanding their possible applications.

Hierarchical structure consisting of ordered silica nanoparticles grown onto carbon fiber (CF) has been fabricated to improve the interfacial properties between the CFs and polymer matrix. To improve the reactivity of CFs, their surface was modified using poly(1,4-phenylene diisocyanate) (PPDI) via in situ polymerization, which also resulted in the distribution of numerous isocyanate groups on the surface of CFs. Silica nanoparticles were modified on the interface of CF-PPDI by chemical grafting method. The microstructure, chemical composition, and interfacial properties of CFs with ordered silica nanoparticles were comprehensively investigated by scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. Results indicated an obvious increase in the interfacial shear strength, compared to that of CF precursor, which was attributed to silica nanoparticles interacting with the epoxy resin. Furthermore, siliconborocarbonitride (SiBCN) ceramic was used as thermal barrier coating to enhance 3D CF architecture substrate antioxidant and ablation properties. Thermogravimetric results show that the thermal stability of the CF with SiBCN ceramic layer has a marked increase at high temperature.

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