Timounay Yousra, Pannwitz Andrea, Klein David M, Biance Anne-Laure, Hoefnagel Marlene E, Sen Indraneel, Cagna Alain, Le Merrer Marie, Bonnet Sylvestre
Teclis Scientific, 22 Ch. Des Prés Secs, 69380 Civrieux d'Azergues, France.
Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC Leiden, The Netherlands.
Langmuir. 2022 Aug 9;38(31):9697-9707. doi: 10.1021/acs.langmuir.2c01391. Epub 2022 Jul 29.
Nonreactive surfactant molecules have long been used and characterized for a wide range of applications in industries, life science, and everyday life. Recently, new types of functional amphiphilic molecules have emerged that bear another function, for example, a light-absorbing action, or catalytic properties. However, the surfactant properties of these molecules remain to date essentially unknown. In this context, we investigated here the interfacial activity of photocatalytic surfactants based on a ruthenium(II) tris-bipyridine core, functionalized with two alkyl tails. We realized a systematic characterization of the surfactant properties of these molecules at a water-air interface and studied the effect of the alkyl chain length and of the counterions (hexafluorophosphate or chloride) on these properties. Our data demonstrate that ruthenium surfactants with chloride counteranions form a denser layer at the interface, but their surfactant properties can dramatically deteriorate when the chain length of the alkyl tail increases, leading to simple hydrophobic molecules with poor surfactant properties for the longest chains (C17). These findings pave the way for a better use and understanding of photocatalytic soft interfaces.
无反应性表面活性剂分子长期以来一直被用于各种工业、生命科学和日常生活应用中，并已得到充分表征。最近，出现了新型功能性两亲分子，它们具有另一种功能，例如光吸收作用或催化特性。然而，这些分子的表面活性剂性质至今基本上仍不为人知。在此背景下，我们在此研究了基于钌（II）三联吡啶核心、带有两条烷基链的光催化表面活性剂的界面活性。我们系统地表征了这些分子在水-空气界面的表面活性剂性质，并研究了烷基链长度和抗衡离子（六氟磷酸盐或氯化物）对这些性质的影响。我们的数据表明，带有氯化物抗衡离子的钌表面活性剂在界面处形成更致密的层，但当烷基链长度增加时，它们的表面活性剂性质会急剧恶化，对于最长的链（C17），会导致具有不良表面活性剂性质的简单疏水分子。这些发现为更好地利用和理解光催化软界面铺平了道路。
