Superthermal Al Atoms as a Reactive-Atom Probe of Fluorinated Surfaces.
Superthermal Al Atoms as a Reactive-Atom Probe of Fluorinated Surfaces.
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DOI：
10.1021/acs.jpca.3c02167
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发表时间：
2023-07-06
影响因子：
2.9
通讯作者：
McKendrick, Kenneth G.
中科院分区：
文献类型：
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作者：
Lane, Paul D.;Gstir, Thomas;Purcell, Simon M.;Swierczewski, Michal;Elstone, Naomi S.;Bruce, Duncan W.;Slattery, John M.;Costen, Matthew L.;McKendrick, Kenneth G.
我们展示了一种新的分析技术来测量氟化材料表面的相对F原子暴露的概念验证。该方法是基于铝原子的反应性原子散射（RAS），在532 nm处的固体铝的脉冲激光烧蚀产生的。用激光诱导荧光（LIF）研究了入射基态Al的性质;在典型的烧蚀注量下，速度分布在45000 K时近似为麦克斯韦分布，最可能的动能为187 kJ mol-1，平均动能为560 kJ mol-1。当这些Al原子撞击全氟固体表面时（聚四氟乙烯，PTFE）或液体（全氟聚醚，PFPE），气相AlF产物可通过AlF A-X带上的LIF清楚地检测到。定量AlF产率进行了比较的一个小的代表性集的一个广泛研究的家庭的离子液体的基础上常见的1-烷基-3-甲基咪唑（[Cnmim]+）阳离子。发现[C2mim][Tf 2N]和[C8 mim][Tf 2N]的产率为（1.9 ± 0.2）：1，含有共同的氟化双（三氟甲基磺酰基）酰亚胺阴离子（[Tf 2N]-）。这是在定量协议与以前的独立的低能离子散射（LEIS）的测量和其他独立的结果表明，较长的阳离子烷基链覆盖了更大部分的液体表面，从而减少阴离子暴露一致。对于不含氟的离子液体[C2mim][EtSO 4]，获得了预期的零结果。这些结果为进一步表征和RAS-LIF方法的这种新变体的潜在应用开辟了道路。
We demonstrate a proof-of-concept of a new analytical technique to measure relative F atom exposure at the surfaces of fluorinated materials. The method is based on reactive-atom scattering (RAS) of Al atoms, produced by pulsed laser ablation of solid Al at 532 nm. The properties of the incident ground-state Al were characterized by laser-induced fluorescence (LIF); at typical ablation fluences, the speed distribution is approximately Maxwellian at ∼45000 K, with a most-probable kinetic energy of 187 kJ mol–1 and a mean of 560 kJ mol–1 When these Al atoms impact the surfaces of perfluorinated solids (poly(tetrafluorethylene), PTFE) or liquids (perfluoropolyether, PFPE), gas-phase AlF products are clearly detectable by LIF on the AlF A–X band. Quantitative AlF yields were compared for a small representative set of a widely studied family of ionic liquids based on the common 1-alkyl-3-methylimidazolium ([Cnmim]+) cation. Yields of (1.9 ± 0.2):1 were found from [C2mim][Tf2N] and [C8mim][Tf2N], containing the common fluorinated bis(trifluoromethylsulfonyl)imide anion ([Tf2N]−). This is in quantitative agreement with previous independent low-energy ion scattering (LEIS) measurements and consistent with other independent results indicating that the longer cationic alkyl chains cover a larger fraction of the liquid surface and hence reduce anion exposure. The expected null result was obtained for the ionic liquid [C2mim][EtSO4] which contains no fluorine. These results open the way for further characterization and the potential application of this new variant of the RAS-LIF method.
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DOI：
10.1007/bf01384861
发表时间：
1988-01-01
期刊：
ZEITSCHRIFT FUR PHYSIK D-ATOMS MOLECULES AND CLUSTERS
影响因子：
--
作者：
FAUBEL, M;SCHLEMMER, S;TOENNIES, JP
通讯作者：
TOENNIES, JP
影响因子：
2.9
作者：
Allan, Mhairi;Bagot, Paul A. J.;McKendrick, Kenneth G.
通讯作者：
McKendrick, Kenneth G.
影响因子：
2.8
作者：
Iimori, T;Iwahashi, T;Kim, D
通讯作者：
Kim, D
影响因子：
1.9
作者：
Hashimoto, Hiroki;Ohno, Atsushi;Kimura, Kenji
通讯作者：
Kimura, Kenji
影响因子：
5.7
作者：
Faust, Jennifer A.;Sobyra, Thomas B.;Nathanson, Gilbert M.
通讯作者：
Nathanson, Gilbert M.