Direct current atmospheric pressure glow discharge generated between a pin‐type solid cathode and a flowing liquid anode as a new tool for silver nanoparticles production

Abstract

Direct current atmospheric pressure glow discharge (dc‐APGD), generated between a pin‐type tungsten solid cathode and the surface of a flowing liquid anode (FLA), was used to synthesize Ag nanoparticles (AgNPs) and gelatin‐stabilized Ag nanoparticles (GEL‐AgNPs) in a flow‐through plasma‐reaction system. To characterize the nanostructures, UV/Vis absorption spectrophotometry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were applied. Resulting GEL‐capped AgNPs were more stable and lower in size than AgNPs. By applying attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT‐IR) and FT‐Raman spectroscopy, possible functionalization of the AgNPs surface by GEL after dc‐APGD treatment was examined. The described method was robust and provided high amounts of the suspensions of nanocolloidal Ag.

Plasma-liquid synthesis of silver nanoparticles and their antibacterial and antifungal applications

“…The plasma-liquid interactions technique for the synthesis of nanoparticles is comparatively new. Different configurations of these methods depending upon power sources and electrodes have been used for the growth of silver nanoparticles [32][33][34].…”

Production of antimicrobial silver nanoparticles modified by alkanethiol self‐assembled monolayers by direct current atmospheric pressure glow discharge generated in contact with a flowing liquid anode

“…A convenient solution to the abovementioned problems can be to apply a cold atmospheric pressure plasma (CAPP)‐based bottom‐up approach, based on generation of selected reactive oxygen and nitrogen species along with hydrated electrons and H radicals, which are involved in reducing AgNPs precursor ions . CAPP‐based methods have been utilized for environment‐friendly AgNP production by several research groups . In the above‐cited studies, different CAPPs are operated either in liquids or in contact with liquids, but in all cases stationary (nonflow‐through) reaction‐discharge systems are used.…”

“…Ag nanostructures’ production via the CAPP‐based bottom‐up approach has been typically carried out in the presence of capping agents, preventing their sedimentation and aggregation . Natural stabilizers such as gelatin, dextran, pectins, sucrose, fructose, or surfactants like sodium dodecyl sulfate, have been used to stabilize NPs synthesized in CAPP‐based systems. Alkanethiols are example of ligands that have been used to cap versatile noble metal nanostructures produced with the aid of non‐CAPP based synthesis procedures .…”

“…TMA allows to obtain stable nanoparticles, as well as noncytotoxic AgNPs with antimicrobial potential . Previously, dc‐APGD or pulse‐modulated radio‐frequency atmospheric pressure glow discharge (pm‐rf‐APGD), operated between the surface of flowing liquid electrodes and pin‐type W electrodes or a gaseous nozzle jet, was used in our group to synthesize Ag or Ag‐Au core‐shell nanostructures. Until now, operating conditions for production of size‐defined Ag nanostructures have only been optimized for the pm‐rf‐APGD reaction‐discharge system; no dc‐APGD reaction‐discharge system has been previously been optimized for that purpose.…”

“…[20] CAPPbased methods have been utilized for environmentfriendly AgNP production by several research groups. [21][22][23][24][25][26][27][28][29][30][31] In the above-cited studies, different CAPPs are operated either in liquids [22] or in contact with liquids, [23,[27][28][29][30] but in all cases stationary (nonflowthrough) reaction-discharge systems are used.…”