An atmospheric pressure microplasma process for continuous synthesis of titanium nitride nanoparticles

- Microplasma process is developed for continuous, one pot synthesis of TiN NPs.
- The obtained NPs are extremely small, uniform and have polycrystalline nature.
- The admixture of H2 during synthesis process can reduce the oxidation of TiN NPs.
- Comparative analysis of key parameters among competing technologies is carried out.
- Microplasma array design is shown as a promising way to scale up the throughput.

This research studies a continuous process for the direct synthesis of titanium nitride nanoparticles assisted by an atmospheric pressure microplasma. Titanium tetrachloride (TiCl4) is used as precursor and nitrogen is used as reacting gas. Composition and microstructure analysis (SEM, EDX, TEM, HRTEM, XRD and XPS) of the synthesized nanoparticles reveals that nanometer-sized titanium nitride (TiN) with polycrystalline nature can be directly prepared by the studied process, and the admixture of H2 gas in plasma during synthesis process can be an effective way to reduce the oxidation of TiN nanoparticles. The influence of the dissipated power and H2 concentration on the optical emission spectra of the microplasma in the operating reactor is investigated. The characteristics gas temperature of the plasma filament is estimated from the emission averaged spectra. A hypothesized mechanism of TiN synthesis in microplasma is illustrated, and comparisons with preceding researches are carried out. Based on process analysis and experimental results, the feasibility of the upscale towards industrial level production is discussed.