摘要:

TOF-SIMS measurements of 1 kDa polystyrene functionalized with a perfluoroalkyl endgroup are presented. Intact oligomer signals in the high mass range and fragment signals in the low mass range are observed (monolayer sample preparation on a silver substrate). The successful functionalization of the polystyrene with the perfluoroalkyl endgroup can be confirmed by the masses at which the intact oligomer signals arise. The high mass region of the spectrum is compared to TOF-SIMS measurements of polystyrene with a proton endgroup. The signal for a polystyrene oligomer with a proton endgroup with a specific degree of polymerization (n) arises at a lower mass because of the absence of the perfluoroalkyl endgroup. The effect of endgroup on the ion transformation probability of intact oligomers is demonstrated in a TOF-SIMS spectrum of a physical mixture (1:1 mole ratio) of polystyrene with a proton endgroup and polystyrene with a perfluoroalkyl endgroup.

ISSN:1055-5269    

DOI:10.1116/1.1247801

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

XPS spectra of Pt black in the as received state showed O and C impurities along with Pt. Anin situtreatment by O2and H2increased Pt intensity and removed a part of oxygen and carbon impurities. The quasihomogeneous model was used for quantitative evaluation applying atomic sensitivity factors published in the literature (Ref. 1). Decomposition of the O 1sregion indicated the presence of adsorbed O, OH, and H2O as well as C—O and C=O species, whereas the C 1sregion could be decomposed to give Pt-C, graphite,CxHypolymer, and oxidized C entities.

ISSN:1055-5269    

DOI:10.1116/1.1247817

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

X-ray photoelectron spectra are reported for a Pt black reduced from an aqueous solution of H2PtCl6by hydrazine and sulfidedex situby 10% H2S+90% H2at 633 K. The Pt 4fline showed predominantly metallic Pt, together with a low intensity shoulder corresponding to PtS and/or adsorbed sulfur. PtS2was not present. Two S 2ppeaks indicated the simultaneous presence of sulfide and sulfate. O 1sand C 1simpurities were also present with peak shapes similar to unsulfided Pt black.

ISSN:1055-5269    

DOI:10.1116/1.1247811

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

We report x-ray photoemission spectra of polystyrene (PS). XPS spectra were measured with the SSI, SSX-100 model, using monochromated AlKαx-rays. We present the survey spectrum (binding energy range of 0–1100 eV) and a narrow spectrum of C 1s. The polymer is used as a reference to study the influence of PS surface modification by rf plasma for biochemical applications.

ISSN:1055-5269    

DOI:10.1116/1.1247812

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

We report x-ray photoemission spectra of poly(methyl methacrylate) (PMMA). XPS spectra were measured with the SSI, SSX-100 model, using monochromated AlKαx-rays. We present the survey spectrum (binding energy range of 0–1100 eV) and narrow spectra of C 1sand O 1s. The polymer is used as a reference to study the influence of PMMA surface modification by rf plasma for biochemical applications.

ISSN:1055-5269    

DOI:10.1116/1.1247813

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

We report x-ray photoemission spectra of poly(tetrafluoroethylene) (PTFE). XPS spectra were measured with the SSI, SSX-100 model, using monochromated AlKαx-rays. We present the survey spectrum (binding energy range of 0–1000 eV) and narrow scans of C 1sand F 1s. The polymer is used as a reference to study the influence of PTFE surface modification by an excimer ultraviolet laser (λ= 193 nm).

ISSN:1055-5269    

DOI:10.1116/1.1247814

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

High quality polythiophene films have been grown using a vapor-deposition process using polythiophene powder as the starting material. The powder was placed in an open quartz crucible (housed in a tungsten basket) and heated by running a high current (10–20 A) through it. The evaporated material was deposited onto a glass substrate placed roughly 3 cm above the crucible. The as-deposited, undoped polythiophene film has been characterized using x-ray photoelectron spectroscopy and is contrasted with the initial polythiophene powder. The reported spectra include survey and high resolution scans for the major photoelectron peaks. It is noted that these results compare favorably with previously published spectra from polythiophene grown using the more conventional chemical or electrochemical methods.

ISSN:1055-5269    

DOI:10.1116/1.1247815

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

Ettringite, found in metamorphosed limestone and also as an important secondary mineral in concrete and certain combustion waste environments, plays an important role in concretion strength development, and in the control ofpH and immobilization of trace elements in alkaline hazardous wastes. Consequently, the ability to identify ettringite via surface-sensitive spectroscopies is important for understanding cementitious mechanisms and the environmental behavior of wastes. We have used x-ray photoelectron spectroscopy (XPS) to study the binding energy of principal photoelectrons from an air-exposed external crystal surface of a well-formed needle-shaped ettringite sample from a bituminous limestone deposit in Asad, Israel. General survey and high resolution spectra were collected under standard operating conditions using a Perkin Elmer Physical Electronics 5200C spectrometer. Adventitious carbon was used as the energy referencing method. Charge-corrected binding energies were identified for the Ca 2p3/2, Ca 2p1/2, Al 2p, S 2p3/2, S 2p1/2, and O 1sphotoelectrons. The mineral contains three oxygen species. Probable loss of waters of hydration resulted in the determination of binding energies for only the hydroxyl and sulfate oxygens. Nominal binding energies for all three species are also provided. These spectra are useful in using XPS to identify ettringite in leaching environments of combustion residues where the secondary mineral precipitated at ash particle surfaces.

ISSN:1055-5269    

DOI:10.1116/1.1247818

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

High quality solid CO2films have been grown on a stainless steel cold-finger using a continuous flow liquid nitrogen system. The solid was formed from research grade (99.995% min. purity) CO2gas using a gas nozzle placed directly over the cold-finger (at a temperature of approximately 77 K). The base pressure in the chamber was less than 5 × 10−10T prior to deposition and upon gas introduction was increased, using a precision leak valve, to approximately 5 × 10−8T. Films were grown in this pressure for 1 h. Gas purity was monitored using a Balzers Prisma QMS 300 quadrapole mass spectrometer. The solid CO2films were characterized using x-ray photolelectron spectroscopy (XPS). The reported spectra include survey and high resolution scans for the major photoelectron peaks.

ISSN:1055-5269    

DOI:10.1116/1.1247819

出版商:American Vacuum Society    

年代:1996

数据来源: AIP

摘要:

XPS data were collected from a pressed potassium chromate powder. The spectra obtained from the as-received powder indicate that single states of K, Cr, and O are present due to K2CrO4. A small amount of C contamination is present in hydrocarbon and carbide forms. Therefore these data can be considered to be characteristic of K2CrO4.

ISSN:1055-5269    

DOI:10.1116/1.1247820

出版商:American Vacuum Society    

年代:1996

数据来源: AIP