In Situ Reactivity and TOF SIMS Analysis of Surfaces Prepared by Soft and Reactive Landing of Mass Selected Ions

Journal Article · Thu Jul 01 04:00:00 EDT 2010 · Analytical Chemistry, 82(13):5718-5727

DOI:https://doi.org/10.1021/ac100734g· OSTI ID:984213

Johnson, Grant E; Lysonski, Michael; Laskin, Julia

An instrument has been designed and constructed that enables in situ reactivity and time of flight secondary ion mass spectrometry (TOF-SIMS) analysis of surfaces prepared or modified through soft- and reactive landing of mass-selected polyatomic cations and anions. The apparatus employs an electrospray ion source coupled to a high transmission electrodynamic ion funnel, two focusing collision quadrupoles, a large 19 mm diameter quadrupole mass filter, and a quadrupole bender that deflects the ion beam, thereby preventing neutral contaminants from impinging on the deposition surface. The ion soft landing apparatus is coupled to a commercial TOF-SIMS instrument permitting the introduction of surfaces into vacuum and SIMS analysis before and after ion deposition without breaking vacuum. To facilitate a comparison of the current TOF-SIMS instrument with the in situ Fourier transform ion cyclotron resonance (FT-ICR-SIMS) deposition apparatus constructed previously, dications of the cyclic peptide Gramicidin S (GS) and the photoactive organonometallic complex ruthenium tris-bipyridine (Ru(bpy)3) were soft landed onto fluorinated self-assembled monolayer (FSAM) on gold surfaces. In both cases similarities and differences were observed in the secondary ion mass spectra, with the TOF-SIMS results, in general, characterized by greater sensitivity, larger dynamic range, less fragmentation, and fewer in-plume reactions than the corresponding FT-ICR-SIMS spectra. The charge reduction kinetics of both the doubly and singly protonated GS cations on the FSAM surface were also examined as was the influence of the primary gallium ion (Ga+) flux on the efficiency of these processes. In addition, we demonstrate that the new instrument enables detailed studies of the reactivity of catalytically active species immobilized by soft- and reactive landing towards gaseous reagents.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 984213
• Report Number(s): PNNL-SA-71728; 30445; 19594; 34913; 30466; KC0302020; KC0302020
• Journal Information: Analytical Chemistry, 82(13):5718-5727, Journal Name: Analytical Chemistry, 82(13):5718-5727 Journal Issue: 82; ISSN 0003-2700
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANIONS
CATIONS
DEPOSITION
EFFICIENCY
ELECTRODYNAMICS
Environmental Molecular Sciences Laboratory
FOCUSING
FRAGMENTATION
GALLIUM IONS
GOLD
ION BEAMS
ION CYCLOTRON-RESONANCE
ION SOURCES
KINETICS
MASS SPECTRA
MASS SPECTROSCOPY
PEPTIDES
QUADRUPOLES
RUTHENIUM
SENSITIVITY
SPECTRA