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Additive methods for manufacturing materials have recently emerged, particularly for the fabrication of three‐dimensional architectures. Because of their long history in thin‐film etching and deposition, plasmas offer unique advantages for many of the materials and surface processes associated with additive manufacturing. Here, we review recent efforts that have been primarily focused on the direct writing of patterned structures and the post‐treatment of printed materials. Different configurations, materials, and applications are presented. Current challenges and a future outlook are also provided. [ABSTRACT FROM AUTHOR]

The use of low‐temperature plasmas for bio‐decontamination and sterilization has been gaining increased attention. In this study, a two‐dimensional array of integrated coaxial microhollow micro‐discharges generated in dry air at atmospheric pressure is used to treat metal surfaces (gas‐phase) and solution (liquid‐phase) contaminated with a known concentration of feline calicivirus (FCV). FCV acts as a surrogate for human norovirus, which is responsible for causing outbreaks of acute gastroenteritis in humans. The decontamination efficacy as well as the primary chemical pathways leading to virus inactivation in both the treatments are studied and compared. It is found that the humidity of the bio‐sample for gas‐phase treatment in dry air is required to achieve >5 log10 reduction in FCV titer within 3 min. The gas‐phase FCV inactivation is found to be due to a combination of ozone (O3) and reactive nitrogen species (RNS), most likely NOx. The liquid‐phase FCV inactivation mechanism is pH‐dependent and is primarily due to RNS, most likely acidified nitrites. O3 has a negligible effect on FCV suspended in solution. Previous studies performed in a batch reactor have shown that the inactivation pathways through O3 and RNS are mutually exclusive due to ozone poisoning at high NxOy concentrations. The present study employs a flow‐through system which avoids accumulation of reactive species and allows for the coexistence of NOx and O3 for the gas residence times used in this study, giving rise to these specific inactivation pathways. [ABSTRACT FROM AUTHOR]

The gas breakdown processes in dc microdischarges with a zeolite cathode (ZC) have been investigated. The electric field has a pronounce effect on the electrical characteristics of the ZC. The effects of electric field and secondary emission were discussed in atmospheric plasmas (AP). A nanoporous surface used as microreactor could enhance the electron emission from the cathode surface, thus reducing the breakdown voltage ( UB). Results indicate that the UB decreases with increasing ZC diameter and decreasing with gap distance. Microdischarges in spatially confined geometries, such as the nanoporous structure of ZCs, present a promising method for the generation and maintenance of stable AP. [ABSTRACT FROM AUTHOR]

This paper reports a method for producing protein arrays on antifouling PEO-like coatings using a 'non-contact' atmospheric pressure helium microplasma array. ToF-SIMS characterization of PEO-like coatings after short plasma treatment revealed the antifouling plasma polymer was largely modified/removed within the microplasma-exposed regions. Incubation of microplasma-patterned PEO-like coatings with a fluorescently labeled streptavidin resulted in selective and uniform protein adsorption within the modified regions. A protein sensing application was demonstrated where a target red fluorescent protein (RFP) was only captured on the anti-RFP functionalized regions. This indicates the adsorbed antibody protein on the microplasma-treated PEO-like regions retained its bioactivity. [ABSTRACT FROM AUTHOR]

Silicon oxide nanowires are synthesised below 523 K by a non-VLS mechanism on different substrates: Fe-0.5 wt.-%Si and Fe-1.5 wt.-%Si alloys and silicon wafers coated or not by 30-nm thick coatings of iron. An Ar-O2 micro-afterglow is used to feed the substrate with oxidising species over an area of ≈2 mm2. In this area, circular bundles of nanowires appear after 15 min and are randomly distributed. Each bundle diameter increases with time and reaches 50 µm. After several hours, bundles overlap and give a continuous carpet of nanowires. TEM analyses show that no iron is found in the nanowires, whatever the substrate. A growth mechanism, based on the emergence of a surface defect is proposed. [ABSTRACT FROM AUTHOR]