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Single‐crystalline {100} faceted TiC is of great significance in theory to a large number of engineering applications owing to its extraordinary catalytic properties. However, the {111} planes are prevalent in conventional TiC powders given their favorable thermodynamic stability during the initial low stoichiometric growth stage. Herein, a disproportionation–decomposition strategy is developed to directly produce Ti and C atoms to synthesize single‐crystalline {100} faceted TiC powders. Outstanding electrochemical performance of TiC {100} crystal planes in terms of the hydrogen evolution reaction is evidenced by an overpotential of 392 mV at 10 mA cm−2, which is 52% lower than that of randomly faceted TiC counterparts (815 mV).

(1−x)CoTiNb 2 O 8 −xZnNb 2 O 6 microwave dielectric ceramics were prepared via the conventional solid-state reaction route with the aim of reducing the τ f value and improving the thermal stability. The phase composition and the microstructure were investigated using X-ray diffraction, Raman spectra, and scanning electron microscopy. A set of phase transitions which were induced by composition had been confirmed via the sequence: rutile structure→coexistence of rutile and columbite phase→columbite phase. For (1−x)CoTiNb 2 O 8 −xZnNb 2 O 6 microwave dielectric ceramics, the addition of ZnNb 2 O 6 content (x = 0-1) led to the decrease of ε r from 62.98 to 23.94. As a result of the high Q × ƒ of ZnNb 2 O 6 ceramics, the increase of ZnNb 2 O 6 content also led to the lower sintering temperatures and the higher Q × ƒ values. The τ f value was reduced from +108.04 (x = 0) to-49.31 ppm/℃ (x = 1). Among them, high density 0.5CoTiNb 2 O 8 −0.5ZnNb 2 O 6 ceramics were obtained at 1175 ℃ with excellent microwave dielectric properties of ε r 39.2, Q × ƒ 40013 GHz, and τ f + 3.57 ppm/℃.

The ultra‐coarse WC‐Co composite powders with a core‐shell structure were effectively prepared by fluidized bed chemical vapor deposition (FBCVD) using CoCl2 precursor. An excellent interfacial bonding was formed between WC and the deposited Co. Defluidization was the major barrier to depositing high‐Co‐content composite powders, which was caused by the adhesion of the deposited Co particles. Decreasing the deposition temperature reduced the cohesion force of the deposited Co particles, which was thus beneficial to preventing the defluidization. Increasing the WC particle size and the gas velocity increased the collision force and benefited the fluidization. The final Co contents were largely dependent on the deposition and fluidization behaviors. For the conditions tested, the optimal deposition temperature was 800°C while the minimum WC particle size suitable for FBCVD was 25 μm.

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