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Electrospray deposition. Graziano Magnano. Nanoscience group School of Physics & Astronomy University of Nottingham. Berlin - 1 st October 07. Graziano Magnano. Berlin - 1 st October 07. Overview. Instrument: principles and settings Results: Deposition of PEO on Si(111)
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Electrospray deposition Graziano Magnano Nanoscience groupSchool of Physics & Astronomy University of Nottingham Berlin - 1st October 07
Graziano Magnano Berlin - 1st October 07 Overview • Instrument: principles and settings • Results: • Deposition of PEO on Si(111) • Deposition of C60 on Au(111) • Deposition of C60 onto PTCDI / Melamine on Au(111) • Ongoing and Future work
Graziano Magnano Berlin - 1st October 07 Electrospray ionisation Electrospray is widely used in mass spectrometry (MS) as an ionisation source for non-volatile molecules and molecules which break down upon heating. It’s possible to create gas phase ions directly from a solution of the molecules of interest. • Especially in MS, electrospray works on large molecules: • To determine the molecular weight and distribuition of polymers and biomolecules, e.g. DNA. • To analyse the sequence of proteins or oligonucleotides. • To analyse drugs, pesticides, carbohydrates or fatty acids with long chains.
Graziano Magnano Berlin - 1st October 07 Electrospray ionisation: principles Ion production in an electrospray ionisation source has three steps: • Aerosol formation; • Aerosol formation; • Desorbed ion formation; • Migration to the sample.
Graziano Magnano Berlin - 1st October 07 Electrospray ionisation: principles Ion production in an electrospray ionisation source has three steps: • Aerosol formation; • Desorbed ion formation; • Migration to the sample. Solvent evaporation Coulombic explosion
Graziano Magnano Berlin - 1st October 07 Electrospray ionisation: principles Ion production in an electrospray ionisation source has three steps: • Aerosol formation; • Desorbed ion formation; • Migration to the sample. S.J. Gaskell, J.Mass Spectrom. 32 (1997) 667
New Deposition Techniques Graziano Magnano Berlin - 1st October 07 Applications Recently, aside from mass spectrometry, novel applications of electrospray have been used to create: • Surface coatings • Functional films • Biological arrays • Electrode coatings
Graziano Magnano Berlin - 1st October 07 Instrumentation We have developed an electrospray deposition system in which the spray occurs In vacuum At atmospheric pressure
Graziano Magnano Berlin - 1st October 07 In vacuum 10-5 torr 10-2 torr
Polymer (PEO) Electrospray deposition in vacuum: Swarbrick,J.C; Taylor, J.B.; O’Shea, J.N. Appl. Surf. Sci. (2006) 252, 5622 Graziano Magnano Berlin - 1st October 07 In vacuum Carbon Nanotubes (CNTs) Electrospray deposition of carbon nanotubes in vacuum: O’Shea J.N., Schulte K. et al. Nanotechnology (18) 035707 (2007)
Graziano Magnano Berlin - 1st October 07 At atmospheric pressure
Graziano Magnano Berlin - 1st October 07 At atmospheric pressure 10-7 torr water-methanol solution
Deposition of PEO on Si(111) Graziano Magnano Berlin - 1st October 07
Deposition of PEO on Si(111) Graziano Magnano Berlin - 1st October 07
Deposition of PEO on Si(111) Graziano Magnano Berlin - 1st October 07
Graziano Magnano Berlin - 1st October 07 Deposition of C60 on Au(111)
Graziano Magnano Berlin - 1st October 07 Deposition of C60 onto PTCDI / Melamine on Au(111) J. A. Theobald, et al., Langmuir, 21, 2005. L. M. A. Perdigão , et al., J. Phys. Chem. B, 110 (25), 2006
Graziano Magnano Berlin - 1st October 07 Deposition of C60 onto PTCDI / Melamine on Au(111) 2 minutes deposition from a ~ 1mg/ml C60 soln. in Tol:MeCN (3:1) A – reduced order area B – Dimers trapped in parallelogram network C – Heptamers in hexagonal network with 2nd layer growth +1.80V, 0.03nA, 102.3nm x 75.3nm
Graziano Magnano Berlin - 1st October 07 Deposition of C60 onto PTCDI / Melamine on Au(111) A +1.80V, 0.03nA, 51.0nm x 33.7nm +1.80V, 0.03nA, 23.9nm x 23.9nm
Graziano Magnano Berlin - 1st October 07 Deposition of C60 onto PTCDI / Melamine on Au(111) B +1.80V, 0.03nA, 51.2nm x 40.6nm
Graziano Magnano Berlin - 1st October 07 Deposition of C60 onto PTCDI / Melamine on Au(111) C +1.80V, 0.03nA, 49.8nm x 30.3nm
Graziano Magnano Berlin - 1st October 07 Ongoing and Future work • Deposition of: • Nanotubes, • PbS, • P3HT, DMP (Soluble Pentacene Precursors), • C60O, Porphyrin, N@C60. • Line of Sight Mass Spectrometry of Electrospray • Detailed inventory of species in electrospray beam • Attempt to deflect using a biased target could give idea of impact energy • New housing for spray generation • Inert atmosphere (Nitrogen) • Precise tip positioning during operation • Heated drying gas
Graziano Magnano Berlin - 1st October 07 Acknowledgements • Dr. James O’ Shea • Chris Satterley, Louise Mayor and Anna Rienzo Funding • EC Marie-Curie Early Stage Researcher Training NetworkProgram MONET: MOLECULAR NETWORKS AT PHASE BOUNDARIES …Thank you for your attention