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Abstract Plasma technology is actively used for nanoparticle synthesis and modification. All plasma techniques share the ambition of providing high quality, nanostructured materials with full control over their crystalline state and functional properties. Pulsed-DC physical/chemical vapour deposition, high power impulse magnetron sputtering, and pulsed cathodic arc are consolidated low-temperature plasma processes for the synthesis of high-quality nanocomposite films in vacuum environment. However, atmospheric arc discharge stands out thanks to the high throughput, wide variety, and excellent quality of obtained stand-alone nanomaterials, mainly core–shell nanoparticles, transition metal dichalcogenide monolayers, and carbon-based nanostructures, like graphene and carbon nanotubes. Unique capabilities of this arc technique are due to its flexibility and wide range of plasma parameters achievable by modulation of the frequency, duty cycle, and amplitude of pulse waveform. The many possibilities offered by pulsed arc discharges applied on synthesis of low-dimensional materials are reviewed here. Periodical variations in temperature and density of the pulsing arc plasma enable nanosynthesis with a more rational use of the supplied power. Parameters such as plasma composition, consumed power, process stability, material properties, and economical aspects, are discussed. Finally, a brief outlook towards future tendencies of nanomaterial preparation is proposed. Atmospheric pulsed arcs constitute promising, clean processes providing ecological and sustainable development in the production of nanomaterials both in industry and research laboratories. 

Abstract Thin layers of polypropylene (PP) have been treated by argon low‐temperature plasmas in an inductively coupled plasma setup. The etched thickness of PP was monitored in situ by means of single‐wavelength ellipsometry. The ellipsometric model of the polymer surface exposed to plasma consists of a UV‐modified layer, a dense amorphous carbon layer because of ion bombardment, and an effective medium approximation layer, which accounts for moderate surface roughness. The etching behavior has been compared to a model based on argon ion beam irradiation experiments. In this approach, surface processes are described in terms of etching yields and crosslinking probabilities as a function of incident fluxes and energies of Ar ions and UV photons. The ion beam model fits well with the plasma etching results.