Gindri Izabelle M, Siddiqui Danyal A, Frizzo Clarissa P, Martins Marcos A P, Rodrigues Danieli C
Department of Bioengineering, University of Texas at Dallas , Richardson, Texas 75080, United States.
Department of Chemistry, Universidade Federal de Santa Maria , Santa Maria, Brazil -97105-900.
ACS Appl Mater Interfaces. 2015 Dec 16;7(49):27421-31. doi: 10.1021/acsami.5b09309. Epub 2015 Dec 7.
Dicationic imidazolium-based ionic liquids (ILs) having bis(trifluoromethylsulfonyl)imide (NTf2) and amino acid-based (methionine and phenylalanine) anionic moieties were synthesized and used to coat titanium surfaces using a dip-coating technique. Dicationic moieties with varying alkyl chains (8 and 10 carbons) and anions with distinct characteristics were selected to understand the influence of IL structural features on deposition profile. X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were used in this study to help elucidate intermolecular interactions within ILs as well as between ILs and TiO2 surfaces and to investigate IL coating morphology. Charge concentration on IL moieties, as well as the presence of functional groups that can interact via hydrogen bond, such as carboxylate and amino groups, were observed to influence the deposition profile. ILs containing amino acids as the anionic moiety were observed to interact strongly with TiO2, which resulted in more pronounced changes in Ti 2p binding energy. The higher hydrophobicity of the IL having NTf2 as the anionic moiety resulted in higher adhesion strength between the IL coating and TiO2.
合成了具有双（三氟甲基磺酰基）亚胺（NTf2）以及基于氨基酸（甲硫氨酸和苯丙氨酸）的阴离子部分的双阳离子咪唑基离子液体（ILs），并采用浸涂技术将其涂覆在钛表面。选择具有不同烷基链（8个和10个碳）的双阳离子部分以及具有不同特性的阴离子，以了解离子液体结构特征对沉积轮廓的影响。本研究中使用X射线光电子能谱（XPS）和原子力显微镜（AFM）来帮助阐明离子液体内部以及离子液体与TiO2表面之间的分子间相互作用，并研究离子液体涂层的形态。观察到离子液体部分的电荷浓度以及可通过氢键相互作用的官能团（如羧基和氨基）的存在会影响沉积轮廓。观察到含有氨基酸作为阴离子部分的离子液体与TiO2强烈相互作用，这导致Ti 2p结合能发生更明显的变化。以NTf2作为阴离子部分的离子液体具有更高的疏水性，这导致离子液体涂层与TiO2之间具有更高的粘附强度。
