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Abstract Manipulating surface charge, electric field, and plasma afterglow in a non-equilibrium plasma is critical to control plasma-surface interaction for plasma catalysis and manufacturing. Here, we show enhancements of surface charge, electric field during breakdown, and afterglow by ferroelectric barrier discharge. The results show that the ferroelectrics manifest spontaneous electric polarization to increase the surface charge by two orders of magnitude compared to discharge with an alumina barrier. Time-resolved in-situ electric field measurements reveal that the fast polarization of ferroelectrics enhances the electric field during the breakdown in streamer discharge and doubles the electric field compared to the dielectric barrier discharge. Moreover, due to the existence of surface charge, the ferroelectric electrode extends the afterglow time and makes discharge sustained longer when alternating the external electric field polarity. The present results show that ferroelectric barrier discharge offers a promising technique to tune plasma properties for efficient plasma catalysis and electrified manufacturing.
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Achieving Low Voltage Plasma Discharge in Aqueous Solution Using Lithographically Defined Electrodes and Metal/Dielectric Nanoparticles
Becauseof thehighdielectricstrengthofwater, it isextremelydifficult todischargeplasmainacontrollablewayin the aqueous phase. By using lithographically defined electrodes andmetal/dielectric nanoparticles, we create electric field enhancementthatenablesplasmadischargeinliquidelectrolytesatsignificantlyreducedappliedvoltages.Here,weusehighvoltage (10−30kV)nanosecondpulse(20ns)dischargestogenerateatransientplasmaintheaqueousphase.Anelectrodegeometrywitha radiusofcurvatureofapproximately10μm,agapdistanceof300μm,andanestimatedfieldstrengthof5×106V/cmresultedina reductionintheplasmadischargethresholdfrom28to23kV.Asecondstructurehadaradiusofcurvatureofaround5μmanda gapdistanceof100μmhadanestimatedfieldstrengthof9×106V/cmbutdidnotperformaswellasthelargergapelectrodes. Addinggoldnanoparticles(20nmdiameter) insolutionfurther reducedthethresholdforplasmadischargeto17kVduetothe electricfieldenhancementatthewater/goldinterface,withanestimatedE-fieldenhancementof4×.Addingaluminananoparticles decoratedwithPtreducedtheplasmadischargethresholdto14kV. Inthisscenario, theemergenceofatriplepointatthejuncture ofalumina,Pt,andwaterresultsinthecoexistenceofthreedistinctdielectricconstantsatasingularlocation.Thisleadstoanotable concentrationof electric field, effectively aiding in the initiationof plasma discharge at a reduced voltage. To gain amore comprehensive and detailed understanding of the electric field enhancement mechanism, we performed rigorous numerical simulations.Thesesimulationsprovidevaluableinsights intotheintricateinterplaybetweenthelithographicallydefinedelectrodes, thenanoparticles, andthe resultingelectricfielddistribution, enablingus toextract crucial informationandoptimize thedesign parameters forenhancedperformance.
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- PAR ID:
- 10538952
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 16
- Issue:
- 26
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 33571 to 33577
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsami.4c06007
