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.
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Coatings for Core–Shell Composite Micro‐Lattice Structures: Varying Sputtering Parameters
Magnetron sputtering has garnered increased attention as a versatile deposition method for generating novel core–shell composite nano‐ and micro‐lattice materials spanning a wide range of properties and functionalities. Sputtering offers an expansive material workspace consisting of a wide range of ceramics, single‐element metals, and alloy systems. However, achieving uniform coatings on such fine‐featured structures remains a challenge. Thus, herein, a foundational assessment of various sputtering configurations, cathode geometries, and deposition parameters is carried out to investigate their implications on the coating thickness and uniformity of 3D micro‐lattice scaffolds. Specifically, tetrahedral‐truss structures fabricated via direct laser writing are coated by leveraging planar and inverted cylindrical magnetron cathodes at select deposition rates, sputtering powers, and Ar working pressures. Both plasma focused ion beam and microtome sectioning techniques are employed to evaluate the cross section of individual struts and assess overall uniformity. Overall, the influence of key sputtering factors on the design and development of core–shell composite nano‐ and micro‐lattice materials is highlighted and a pathway for future sputter coating optimization on these complex structures is provided.
- NSF-PAR ID:
- 10445807
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Engineering Materials
- Volume:
- 24
- Issue:
- 4
- ISSN:
- 1438-1656
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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