Influence of Magnetic Nanoparticles and Magnetic Stress on an Ionic Liquid Electrospray Source

Two electrospray sources were developed to operate on an ionic liquid ferrofluid; one source was a pressure‑fed capillary electrospray source and the other was a novel electrospray source which used a magnetically‑induced instability to produce a peak from which an electric field could extract electrospray. Multiple characteristics of electrospray operation were examined for both sources using faraday plates/cups, a quartz crystal microbalance, a retarding potential analyzer, and a time-of-flight mass spectrometer. The ILFF electrosprays for a capillary source were shown to operate in a mixed ion/droplet regime. The mass flow of the electrospray beam was primarily transported by larger particles (potential droplets) within it. The magnetic nanoparticles increased the required flowrate and extraction potential of the source, as well as the emission current at a given flowrate. The nanoparticles also influenced the beam divergence and energy of an electrospray, increasing and decreasing each respectively with higher concentrations of NPs. The magnetic field had significant influence on the required flowrate of the electrospray, as it reduced the minimum stable flowrate by upwards of 16 percent. It also was shown to decreased the emission current of ILFF electrosprays for a given flowrate, while concurrently increasing the beam energy of particles in the electrospray. Other effects of magnetic field on electrospray characteristics were either inconclusive or insignificant

Influence of Magnetic Nanoparticles and Magnetic Stress on an Ionic Liquid Electrospray Source

Two electrospray sources were developed to operate on an ionic liquid ferrofluid; one source was a pressure?fed capillary electrospray source and the other was a novel electrospray source which used a magnetically?induced instability to produce a peak from which an electric field could extract electrospray. Multiple characteristics of electrospray operation were examined for both sources using faraday plates/cups, a quartz crystal microbalance, a retarding potential analyzer, and a time-of-flight mass spectrometer. The ILFF electrosprays for a capillary source were shown to operate in a mixed ion/droplet regime. The mass flow of the electrospray beam was primarily transported by larger particles (potential droplets) within it. The magnetic nanoparticles increased the required flowrate and extraction potential of the source, as well as the emission current at a given flowrate. The nanoparticles also influenced the beam divergence and energy of an electrospray, increasing and decreasing each respectively with higher concentrations of NPs. The magnetic field had significant influence on the required flowrate of the electrospray, as it reduced the minimum stable flowrate by upwards of 16 percent. It also was shown to decreased the emission current of ILFF electrosprays for a given flowrate, while concurrently increasing the beam energy of particles in the electrospray. Other effects of magnetic field on electrospray characteristics were either inconclusive or insignificant