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The preparation and storage of aluminum nanoparticles pose significant challenges due to their high chemical reactivity. This paper proposes a one-step method for the production of carbon-coated aluminum nanoparticles using an argon protective arc in a liquid nitrogen environment. The emission spectra of the arc validate that the method proposed in this paper can effectively mitigate the adverse impact of impurity gases such as oxygen and water on the product without the need for expensive vacuum equipment. The obtained nanoparticles underwent characterization through high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman analysis, thermogravimetric analysis, and dynamic light scattering. The characterization results demonstrate the successful synthesis of carbon-coated aluminum nanoparticles with nitrogen-doped fullerene shells. With an increase in arc current, the nanoparticles exhibit a corresponding enlargement in diameter, accompanied by a broader distribution. The characterization of the electrode erosion suggests that the aluminum droplet ejection plays a more important role in the nanoparticle generation process as the arc current increases. Optimized strategies are proposed to increase the percentage of successfully-formed carbon-coated aluminum nanoparticles. • One-step preparation of carbon-coated aluminum nanoparticles. • Arc discharge in liquid environment without vacuum and sealing equipment. • Core-shell structure: Al core wrapped in N-doped fullerenes. • The arc current impacts electrode erosion pattern and product characteristics. [ABSTRACT FROM AUTHOR]

Abstract: Based on two-temperature magnetic hydrodynamic (MHD) model, the influence of saddle-shaped distributed axial magnetic field (AMF, linearly increases along radial position) and bell-shaped distributed AMF (linearly decreases along radial position) on plasma loss and heat flux density to anode in subsonic high-current vacuum arc (HCVA) is simulated and analyzed. According to the simulation results, the saddle-shaped AMF can more effectively inhibit plasma loss from arc column than that of bell-shaped AMF. Comparisons between simulation results and experimental results further verify the correctness of model and simulation. [Copyright &y& Elsevier]

Abstract: A magnetic field parallel to the carbon arc in water was used to increase the directionality of moving carbon particles and generate carbon nano-materials. The products were analyzed and compared with those obtained without a magnetic field. The study shows that the purity and quality of multi-walled carbon nanotubes in the cathode deposition formed by an arc in water with a magnetic field were both improved, and cylinder-like carbon structures were also found in the deposition. The influence of the magnetic field on the formation of the products was analyzed. [Copyright &y& Elsevier]