The paper presents the effects of plasma treatment on agricultural seeds. Cucumber and pepper seeds, widely used in agriculture, were treated using the Diffuse Coplanar Surface Barrier Discharge (DCSBD) at atmospheric pressure in ambient air. The plasma treatment (4 s for pepper, 20 s for cucumber) led to an improvement of germination and germinating power. XPS confirmed chemical changes on the seed surface. The surface morphology of the plasma treated seeds showed no evidence of structural damage. The conclusion is that DCSBD proves to be able to reduce some of the microorganisms and pathogens affecting the seeds. Thanks to their technical simplicity and easy scaling‐up, DCSBD plasma sources open new opportunities for atmospheric pressure plasma application in the agricultural industry.

The influence of the interplay between central (Q C ) and secondary (Q S ) channel gas flow, as well as delivered microwave power (P MW ), during graphene nanosheet synthesis in a dualchannel electrode configuration of a microwave plasma torch at atmospheric pressure by ethanol decomposition was investigated. In the dual-channel configuration, plasma discharge can be sustained, even at high flow rates of ethanol, due to the separation of argon working and carrier gas. The plasma discharge instability was mainly influenced by an increase in the central channel flow, and a minor influence of secondary channel flow was also observed. With respect to the dependence on experimental conditions, the synthesized nanopowder consisted of amorphous carbon and nanocrystalline diamond nanoparticles, defective carbon nanosheets or few-layer graphene nanosheets. The synthesized nanosheets are rectangular in shape with a lateral size of several hundreds of nanometres and a few graphene layers thick, as shown by electron microscopy. Raman and x-ray photoelectron spectroscopy analysis of the synthesized nanosheets showed a good degree of graphitization, low oxygen content and increasing quality of graphene nanosheets with increasing microwave power. The number of defects in the synthesized nanosheets could be decreased by elongation of the graphene nanosheet assembly zone. An increase in the C 2 /C emission line intensity ratio correlated with a decrease in the number of defects in the graphene nanosheet structure. The achieved conversion yield of ethanol into graphene nanosheets was 8.3%, without negatively affecting the nanosheet quality.

Polyoxazolines are a new promising class of polymers for biomedical applications. Antibiofouling polyoxazoline coatings can suppress bacterial colonization of medical devices, which can cause infections to patients. However, the creation of oxazoline-based films using conventional methods is difficult. This study presents a new way to produce plasma polymerized oxazoline-based films with antibiofouling properties and good biocompatibility. The films were created via plasma deposition from 2-methyl-2-oxazoline vapors in nitrogen atmospheric pressure dielectric barrier discharge. Diverse film properties were achieved by increasing the substrate temperature at the deposition. The physical and chemical properties of plasma polymerized polyoxazoline films were studied by SEM, EDX, FTIR, AFM, depth-sensing indentation technique, and surface energy measurement. After tuning of the deposition parameters, films with a capacity to resist bacterial biofilm formation were achieved. Deposited films also promote cell viability.

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