Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-08T13:26:50.056Z Has data issue: false hasContentIssue false

Probing electrically driven nanojets by energy and mass analysis in vacuo

Published online by Cambridge University Press:  23 November 2021

Luis Javier Perez-Lorenzo
Affiliation:
Department of Mechanical Engineering and Materials Science, Yale University, 9 Hillhouse Avenue, New Haven, CT 06511, USA
Juan Fernandez de la Mora*
Affiliation:
Department of Mechanical Engineering and Materials Science, Yale University, 9 Hillhouse Avenue, New Haven, CT 06511, USA
*
 Email address for correspondence: [email protected]

Abstract

Time of flight (TOF) and energy analysis in vacuum are used in series to determine jet velocity Uj, diameter dj, electrical potential Vj and energy dissipated ΔV at the breakup point of electrified nanojets of the ionic liquid 1-Ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate (EMI-FAP) (Ignat'ev et al., J. Fluorine Chem., vol. 126, issue 8, 2008, pp.1150–1159). The full spray is periodically gated by a grid held at a high voltage Vg, and received at a collector where the measured flight times provide the distribution of drop speeds u. Varying Vg provides the bivariate distribution of drop energies ξ and velocities. The collector plate, centred with the beam axis, is divided into eight concentric rings, yielding the angular distribution of the spray current, and high resolution (u,ξ) values in the whole spray. The energies of various particles of given u are all well defined, but depend uniquely on u, even though u and ξ are in principle independent experimental variables. Slow and fast particles have energies respectively well above and below the capillary voltage Ve (1.64 kV). As previously shown by Gamero-Castaño & Hruby (J. Fluid Mech., vol. 459, 2002, pp. 245–276), this behaviour is due to the 2-stage acceleration process, first jointly in the jet for all particles, and then separately for free flying drops or ions of different mass/charge. The measured two-dimensional distributions of u and ξ provide the jet velocity Uj (~0.44 km s−1) and electrical potential Vj (1.2 kV) at the breakup point. All molecular ions originate near the breakup point rather than the meniscus neck. A measurable fraction of anomalously fast drops is observed that must come from Coulomb fissions of the main drops.

Type
JFM Papers
Copyright
© The Author(s), 2021. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Benassayag, G., Sudraud, P. & Jouffrey, B. 1985 In situ high voltage tem observation of an electrohydrodynamic (EHD) ion source. Ultramicroscopy 16 (1), 18.CrossRefGoogle Scholar
Collins, R.T., Sambath, K., Harris, M.T. & Basaran, O. 2013 Universal scaling laws for the disintegration of electrified drops. Proc. Natl Acad. Sci. USA 110 (13), 49054910.CrossRefGoogle ScholarPubMed
Cook, K.D. 1986 Electrohydrodynamic mass-spectrometry. Mass Spectrom. Rev. 5 (4), 467519.CrossRefGoogle Scholar
Fedkiw, T.P. & Lozano, P.C. 2009 Development and characterization of an iodine field emission ion source for focused ion beam applications. J. Vac. Sci. Technol. B 27 (6), 26482653.CrossRefGoogle Scholar
Fernández de la Mora, J. 2007 The fluid dynamics of Taylor cones. Annu. Rev. Fluid Mech. 39 (1), 217243.CrossRefGoogle Scholar
Gabovich, M.D. 1983 Liquid-metal ion emitters. Sov. Phys. Uspekhi 26 (5), 447455.CrossRefGoogle Scholar
Gamero-Castaño, M. 2008 Characterization of the electrosprays of 1-ethyl-3-methylimidazolium Bis(Trifluoromethylsulfonyl) imide in vacuum. Phys. Fluids 20, 032103.CrossRefGoogle Scholar
Gamero-Castaño, M. 2010 Energy dissipation in electrosprays and the geometric scaling of the transition region of cone-jets. J. Fluid Mech. 662, 493513.CrossRefGoogle Scholar
Gamero-Castaño, M. 2019 Dissipation in cone-jet electrosprays and departure from isothermal operation. Phys. Rev. E 99 (6), 15.CrossRefGoogle ScholarPubMed
Gamero-Castaño, M. & Cisquella-Serra, A. 2021 Electrosprays of highly conducting liquids: a study of droplet and ion emission based on retarding potential and time-of-flight spectrometry. Phys. Rev. Fluids 6 (1), 013701.CrossRefGoogle Scholar
Gamero-Castaño, M. & Fernández de la Mora, J. 2000 Direct measurement of Ion evaporation kinetics from electrified liquid surfaces. J. Chem. Phys. 113 (2), 815832.CrossRefGoogle Scholar
Gamero-Castaño, M. & Hruby, V. 2001 Electrospray as a source of nanoparticles for efficient colloid thrusters. J. Propul. Power 17 (5), 977987.CrossRefGoogle Scholar
Gamero-Castaño, M. & Hruby, V. 2002 Electric measurements of charged sprays emitted by cone-jets. J. Fluid Mech. 459, 245276.CrossRefGoogle Scholar
Gamero-Castaño, M. & Magnani, M. 2018 Numerical simulation of electrospraying in the cone-jet mode. J. Fluid Mech. 859, 247267.CrossRefGoogle Scholar
Gamero-Castaño, M. & Magnani, M. 2019 The minimum flow rate of electrosprays in the cone-jet mode. J. Fluid Mech. 876, 553572.CrossRefGoogle Scholar
Gañán-Calvo, A.M. 1997 Cone-jet analytical extension of Taylor's electrostatic solution and the asymptotic universal scaling laws in electrospraying. Phys. Rev. Lett. 79, 217220.CrossRefGoogle Scholar
Gañán-Calvo, A.M., López-Herrera, J.M., Herrada, M.A., Ramos, A. & Montanero, J.M. 2018 Review on the physics of electrospray: from electrokinetics to the operating conditions of single and coaxial Taylor cone-jets, and AC electrospray. J. Aerosol Sci. 125, 3256.CrossRefGoogle Scholar
Guerrero, I., Bocanegra, R., Higuera, F.J. & Fernandez de la Mora, J. 2007 Ion evaporation from taylor cones of propylene carbonate mixed with ionic liquids. J. Fluid Mech. 591, 437459.CrossRefGoogle Scholar
Higuera, F.J. 2003 Flow rate and electric current emitted by a Taylor cone. J. Fluid Mech. 484, 303327.CrossRefGoogle Scholar
Ignat'ev, N.V., Welz-Biermann, U., Kucheryna, A., Bissky, G. & Willner, H. 2005 New ionic liquids with tris(perfluoroalkyl)trifluorophosphate (FAP) anions. J. Fluorine Chem. 126 (8), 11501159.CrossRefGoogle Scholar
Krohn, V. 1961 Liquid metal droplets for heavy particle propulsion. In Electrostatic Propulsion, pp. 73–80. American Institute of Aeronautics and Astronautics.CrossRefGoogle Scholar
Larriba, C., Castro, S., Fernandez De La Mora, J. & Lozano, P. 2007 Monoenergetic source of kilodalton ions from taylor cones of ionic liquids. J. Appl. Phys. 101 (8), 16.CrossRefGoogle Scholar
Lozano, P. & Martinez-Sanchez, M. 2004 Ionic liquid ion sources: suppression of electrochemical reactions using voltage alternation. J. Colloid Interface Sci. 280 (1), 149154.CrossRefGoogle ScholarPubMed
Miller, C.E. & Lozano, P.C. 2020 Measurement of the dissociation rates of ion clusters in ionic liquid ion sources. Appl. Phys. Lett. 116 (25), 38.CrossRefGoogle Scholar
Perez-Lorenzo, L.J. & Fernandez de la Mora, J. 2019 A new facility for electrospray propulsion studies withspatial resolution of the full beam and high-resolution mass analysis: remarks on drop versus ion propulsion. In AFOSR Contractors Meeting Los Angeles, CA.Google Scholar
Richardson, C.B., Pigg, A.L., & Hightower, R.L. 1989 On the stability limit of charged droplets. Proc. R. Soc. Lond. A 422, 319328.Google Scholar
Romero-Sanz, I., Bocanegra, R., Fernández de la Mora, J., & Gamero-Castaño, M. 2003 Source of heavy molecular ions based on Taylor cones of ionic liquids operating in the pure ion evaporation regime. J. Appl. Phys. 94(5), 35993605.CrossRefGoogle Scholar
Safarov, J., Lesch, F., Suleymanli, K., Aliyev, A., Shahverdiyev, A., Hassel, E. & Abdulagatov, I. 2017 Viscosity, density, heat capacity, speed of sound and other derived properties of 1-butyl-3-methylimidazolium tris(pentafluoroethyl) trifluorophosphate over a wide range of temperature and at atmospheric pressure. J. Chem. Engng Data 62 (10), 36203631.CrossRefGoogle Scholar
Seki, S., Serizawa, N., Hayamizu, K., Tsuzuki, S., Umebayashi, Y., Takei, K. & Miyashiro, H. 2012 Physicochemical and electrochemical properties of 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate and 1-ethyl-3-methylimidazolium tetracyanoborate. J. Electrochem. Soc. 159 (7), 967971.CrossRefGoogle Scholar
Součková, M., Klomfar, J. & Pátek, J. 2012 Temperature dependence of the surface tension and 0.1 MPa density for 1-C n-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate with n = 2, 4, and 6. J. Chem. Thermodyn. 48, 267275.CrossRefGoogle Scholar
Tang, K. & Gomez, A. 1994 On the structure of an electrostatic spray of monodisperse droplets. Phys. Fluids 6, 2317.CrossRefGoogle Scholar
Yang, W., Duan, H., Li, C. & Deng, W. 2014 Crossover of varicose and whipping instabilities in electrified microjets. Phys. Rev. Lett. 112, 5.CrossRefGoogle ScholarPubMed
Supplementary material: File

Perez-Lorenzo and Fernandez de la Mora supplementary material

Perez-Lorenzo and Fernandez de la Mora supplementary material

Download Perez-Lorenzo and Fernandez de la Mora supplementary material(File)
File 4 MB