Spray mechanism in paper spray ionization

Images and droplet size measurements show that paper spray operates in two distinct spray modes. Mode 1 occurs in solvent-rich systems in which multiple Taylor conejets are created producing droplets of a range of sizes. Mode 2 occurs at low solvent flow rates and the higher currents (∼1 uA) suggest a contribution from corona discharge. The latter experiment produces monodispersed droplet sizes. A distinguishing feature of paper spray in both modes is a fixed droplet velocity independent of droplet size.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (158 K)Download as PowerPoint slideHighlights► We describe the spray modes during paper spray ionization. ► When solvent-rich, paper spray produces multimodal droplet distributions. ► Solvent-deficient paper spray produces monodisperse drops and a corona discharge. ► Microfiber structures enhance the electric field near the Taylor cone(s).