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Titanium carbide (TiC) fibers are attractive functional materials that find application in the areas of energy, environment, and biology. Herein, a simple precursor route is designed to prepare TiC fibers by means of electrospinning. The precursor is prepared by adding polyvinylpyrrolidone (PVP) to as-synthesized polytitanoxane (PTO), and the synthesis process, structure, and thermal behavior of the resulting TiC fibers are analyzed. Smooth and continuous precursor fibers with a uniform diameter of ~1.22 μm are obtained after the electrospinning of the precursor. With increase in the preparation temperature, the phase composition of the fibers evolves into TiC from TiCxOy via pyrolysis and carbothermal reduction. Chemical-state analysis results show that the surface of as-prepared TiC fibers exhibits very weak oxidation, thus leading to TiO2 and TiCxOy formation. In addition, all the prepared fibers show uniform morphologies without adhesion. With the proposed approach, continuous TiC fibers with a diameter of ~0.55 μm can be obtained.

Herein, in-situ Zr3[Al(Si)]4C6-based composites with 10–40 vol% ZrB2–SiC (2-to-1 molar ratio) were prepared by hot-pressing sintering at 1850 °C. The simultaneously incorporated ZrB2–SiC constitute multicomponent reinforcements and has a synergistic effect on the matrix, which improves the sinterability, mechanical properties, and oxidation resistance of materials. It is found that both of the toughness and strength increase first and then decrease with the increasing content of ZrB2–SiC, while the hardness increases near linearly. Zr3[Al(Si)]4C6–ZrB2–SiC shows high strength (623 MPa), toughness (7.59 MPa m1/2), and hardness (18.6 GPa), which can be ascribed to the synergistic mechanisms of the binary ZrB2–SiC including fine-grained strengthening, particle reinforcement, intragranular microstructure, grain's pull-out and crack bridging, etc. In addition, the oxidation kinetics of as-prepared materials follow the parabolic law, and the composite shows a low oxidation rate of 0.87 × 10−5 kg2 m−4 s−1 when oxidized at 1400 °C.

Pt-SnO2 catalysts supported on modified carbon fibers were prepared by an electrospinning method with polyacrylonitrile (PAN) as the carrier and polyvinylidene fluoride (PVDF) as the pore-forming agent. The physical-chemical property and catalytic performance of the as-synthesized composites were characterized by XRD, SEM, BET, Chronoamperometry and AC impedance. The results showed that the porous structure in the carbon fibers was formed after calcination at 800 °C in the presence of PVDF. When the weight ratio of PAN/PVDF was 1:0.8, the porous carbon fibers had the largest surface area of 374.85 m2 g−1, which was 3.3 times of carbon fibers prepared without PVDF. The in-situ formed porous structure in carbon fibers can provide more active sites for the catalytic reaction. Therefore, the porous carbon fiber supported Pt-SnO2 catalysts exhibited the best catalytic performance with the ethanol oxidation peak current value of 140.14 mA cm−2 and the electrochemical active area up to 54.296 m2 g−1. DEFC performance showed that the best potential was 0.7 V and the maximum of power density was 18.1 mW cm−2 when the oxygen flow rate and the temperature were 100 mL min−1 and 80 °C, respectively.

The oxidation behavior of Zr3[Al(Si)]4C6-matrix composites reinforced by adjusted content of ZrB2-SiC with fixed molar ratio of 2:1 was investigated. The composites were exposed to air at medium temperatures, and the oxidation kinetics of the composites generally follow a parabolic law. With the ZrB2-SiC content increasing from 0 to 40vol.%, the oxidation weight gain per unit surface area (Δw/s) and oxidation rate constant (k p) of the specimens increase and then decrease at the same oxidation conditions. The high content of ZrB2-SiC is benefit for improving the oxidation resistance of the composites. And, the lowest k p of the composite incorporated with 40vol.%ZrB2-SiC is about 2.43×10−6kg2·m−4·s−1 when oxidized at 1100°C, which is stillhigherthan that of monolithic Zr3[Al(Si)]4C6. In addition, the phase composition and microstructure of oxidation products and the oxidation mechanism of materials were analyzed and discussed.