Paper Title
Supersonic Mass-Selected Electrospray Deposition System-based Studies of Complex Molecules on Surfaces

Abstract
Depositing molecules onto surfaces represents a gradual change in the range of scientific research by comparing electrospray ion beam deposition and conventional deposition techniques. In addition, depositing the molecules under ultra-high vacuum conditions aids to minimize the effect of atmospheric contaminants means maintaining the cleanliness of the surface during deposition. The electrospray ion beam deposition technique has facilitated the in-situ characterization to deposit enormous molecules on surfaces, for example, large organic molecules, inorganic clusters, nanoparticles, dye-sensitizers of photovoltaics, water-splitting solar cells, and biomolecules in ultra-high vacuum environments (UHV) due to their fragile, thermal instability, and non-volatile molecules. On the other hand, this technique overcomes the limitations of thermal evaporation or sublimation via a Knudsen cell (also known as a K-cell), which is considered only suitable for depositing small volatile and thermally stable molecules. This work introduces the electrospray ion beam deposition technique which is incorporating a supersonic mass selection with simple electrostatic deflection to achieve the mass selection. The supersonic mass selection (called mass filtering) plays an important role by removing residual solvent from the original solution and contaminants, as well as determining the nanoparticle sizes, and molecular masses. The dataset was presented here in order to demonstrate the separation of fluorescein and ferrocene (i.e., exploring the use of deflection plates to separate out the two molecules from the solution to deposit selectively one or the other). As well as, it was explored defocusing within the Einzel lens using a sodium chloride solution (NaCl) with X-ray photoelectron spectroscopy (XPS) measurements. Keywords - Electrospray Deposition, Molecules, Mass-Selection, Technique