title: Characterization of pyridine-octanethiolated gold nanoparticles: desorption kinetics by thermal analysis mass spectrometry.
abstract: We describe a synthetic pathway to the formation of stable pyridine-functionalized octanethiolate mixed monolayer-protected Au clusters (MPCs). The spectroscopic characterization data of MPCs using NMR, UV-Vis, TEM, XPS, and thermal-analysis-mass techniques are discussed. TEM analysis showed that spherical nanoclusters of 3-5 nm were produced. Furthermore, the particle sizes are uniform with a narrow size distribution. The pyridine-functionalized MPCs formed 2D superlattices with hexagonal packing covering on the carbon-coated copper grids during the toluene evaporation. For all samples, the S 2p(3/2) and 2p(1/2) components that appeared at approximately 162 and approximately 163 eV, respectively, in the XPS spectra compare very well with the typical value of chemisorbed S species. Thermal analysis mass spectrometer was used to analyze desorption behavior of octanethiolated MPCs or pyridine-functionalized mixed MPCs. The TA-mass spectra have revealed that MCPs exist monomer and dimer desorption behavior from monomeric thiolate adsorbed on the surface.
authors.affiliation: Department of Chemistry, Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, Kaohsiung, Taiwan.
authors.forename: Teng-Yuan
authors.initials: TY
authors.lastname: Dong
authors.forename: Chih-Hung
authors.initials: CH
authors.lastname: Tu
authors.forename: Heng-Hsi
authors.initials: HH
authors.lastname: Wu
authors.forename: Chienlin
authors.initials: C
authors.lastname: Huang
authors.forename: Yuan-Sing
authors.initials: YS
authors.lastname: Lin
authors.forename: Ming-Cheng
authors.initials: MC
authors.lastname: Lin
mesh_terms: D002244:Carbon / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D036103:Nanotechnology / Q000379:methods*; D009795:Octanes / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
chemical_list: D009795:Octanes; D011725:Pyridines; D013438:Sulfhydryl Compounds; D002244:Carbon; D006046:Gold; C023666:pyridine; C026728:octane