Counterion Binding in Adsorbed Surfactant Films Studied by Surface Tensiometry and Total Reflection XAFS Spectroscopy

A bent crystal Laue analyser (BCLA) is an X-ray energy analyser used for fluorescence X-ray absorption fine-structure (XAFS) spectroscopy to separate the fluorescence X-ray emission line of a target atom from the elastic scattering X-rays and other fluorescence emission lines. Here, the feasibility of the BCLA for total reflection fluorescence XAFS (TRF-XAFS), which has a long X-ray footprint on the substrate surface owing to grazing incidence, was tested. The focal line of the BCLA was adjusted on the X-ray footprint and the XAFS signal for one monolayer of Pt deposited on a 60 nm Au film with high sensitivity was obtained. Although range-extended XAFS was expected by the rejection of Au fluorescence arising from the Au substrate, a small glitch was found in the Au L 3 edge because of the sudden change of the complex refraction index of the Au substrate at the Au edge. This abnormal spectrum feature can be removed by reflectivity correction using Au foil absorption data. BCLA combined with TRF-XAFS spectroscopy (BCLA + TRF-XAFS) is a new technique for the in situ surface analysis of highly dispersed systems even in the presence of a liquid overlayer.

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Effect of the Headgroup Structure on Counterion Binding in Adsorbed Surfactant Films Investigated by Total Reflection X-ray Absorption Fine Structure Spectroscopy

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.20180167 ◽

2018 ◽

Vol 91 (10) ◽

pp. 1487-1494

Author(s):

Yosuke Imai ◽

Yuhei Tokiwa ◽

Shusaku Ueno ◽

Hajime Tanida ◽

Iwao Watanabe ◽

...

Keyword(s):

Fine Structure ◽

Total Reflection ◽

Counterion Binding ◽

X Ray ◽

Absorption Fine ◽

X Ray Absorption

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Contribution of x-ray total reflection to the background intensity in EPMA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134600 ◽

1990 ◽

Vol 48 (2) ◽

pp. 202-203

Author(s):

Werner P. Rehbach ◽

Peter Karduck

Keyword(s):

Atomic Number ◽

Target Material ◽

Total Reflection ◽

Background Intensity ◽

X Rays ◽

Characteristic Radiation ◽

X Ray

In the EPMA of soft x rays anomalies in the background are found for several elements. In the literature extremely high backgrounds in the region of the OKα line are reported for C, Al, Si, Mo, and Zr. We found the same effect also for Boron (Fig. 1). For small glancing angles θ, the background measured using a LdSte crystal is significantly higher for B compared with BN and C, although the latter are of higher atomic number. It would be expected, that , characteristic radiation missing, the background IB (bremsstrahlung) is proportional Zn by variation of the atomic number of the target material. According to Kramers n has the value of unity, whereas Rao-Sahib and Wittry proposed values between 1.12 and 1.38 , depending on Z, E and Eo. In all cases IB should increase with increasing atomic number Z. The measured values are in discrepancy with the expected ones.

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