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Yan C, Paige MF. Pattern Formation in Phase-Separated Langmuir and Langmuir Monolayer Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:8357-8369. [PMID: 34236880 DOI: 10.1021/acs.langmuir.1c00642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Mixed monolayer films comprising hydrogenated and fluorinated surfactants can undergo phase separation to produce interfaces with diverse structures at the micrometer and nanometer scales. This review discusses our progress over the past decade to probe the relationship that exists between the molecular structure of the surfactants that comprise the films and the overall patterns formed in the monolayers. We review two main classes of mixed perfluorocarbon-hydrocarbon surfactant systems, including fatty acids and a recently developed family of EDTA-based gemini surfactants. In addition to summarizing the state-of-the-art of this field, the key scientific questions and relationships that require further elucidation are discussed, along with directions for continuing research into this fascinating area of research.
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Affiliation(s)
- Ci Yan
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada
| | - Matthew F Paige
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada
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Tao DD, Wei JH, Yan XS, Wang Q, Kou BH, Chen N, Jiang YB. Helical nanofibers of N-(perfluorooctanoyl)cysteine ethyl ester in coordination polymers of Ag . Chem Commun (Camb) 2020; 56:15133-15136. [PMID: 33165457 DOI: 10.1039/d0cc05989g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We propose using the formation of coordination polymers of Ag+ to probe differences between the perfluorinated alkyl chain and the alkyl chain by deriving a thiol ligand, N-(perfluoroalkanoyl)cysteine. Rapid formation in EtOH of P-/M-helical nanofibrils of high thermostability was found for N-(perfluorooctanoyl)-l-/d-cysteine ethyl esters at the μM level upon mixing with Ag+, but not for the octanoyl counterpart. This difference was also observed in terms of circular dichroism-enantiomeric excess dependence.
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Affiliation(s)
- Dan-Dan Tao
- Department of Chemistry, College of Chemistry and Chemical Engineering, the MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, and iChEM, Xiamen University, Xiamen 361005, China.
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Albano G, Pescitelli G, Di Bari L. Chiroptical Properties in Thin Films of π-Conjugated Systems. Chem Rev 2020; 120:10145-10243. [PMID: 32892619 DOI: 10.1021/acs.chemrev.0c00195] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chiral π-conjugated molecules provide new materials with outstanding features for current and perspective applications, especially in the field of optoelectronic devices. In thin films, processes such as charge conduction, light absorption, and emission are governed not only by the structure of the individual molecules but also by their supramolecular structures and intermolecular interactions to a large extent. Electronic circular dichroism, ECD, and its emission counterpart, circularly polarized luminescence, CPL, provide tools for studying aggregated states and the key properties to be sought for designing innovative devices. In this review, we shall present a comprehensive coverage of chiroptical properties measured on thin films of organic π-conjugated molecules. In the first part, we shall discuss some general concepts of ECD, CPL, and other chiroptical spectroscopies, with a focus on their applications to thin film samples. In the following, we will overview the existing literature on chiral π-conjugated systems whose thin films have been characterized by ECD and/or CPL, as well other chiroptical spectroscopies. Special emphasis will be put on systems with large dissymmetry factors (gabs and glum) and on the application of ECD and CPL to derive structural information on aggregated states.
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Affiliation(s)
- Gianluigi Albano
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Gennaro Pescitelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Lorenzo Di Bari
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
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Dey B, Debnath P, Chakraborty S, Deb B, Bhattacharjee D, Majumdar S, Hussain SA. Study of Compression-Induced Supramolecular Nanostructures of an Imidazole Derivative by Langmuir-Blodgett Technique. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:8383-8394. [PMID: 28791869 DOI: 10.1021/acs.langmuir.7b01750] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this communication, we report the design and synthesis as well as the supramolecular assembly behavior of a 2,4,5-triaryl imidazole derivative (compound 1) at the air-water interface and in thin films using Langmuir-Blodgett (LB) technique. The main idea for such a chemical structure is that the long alkyl chain and N-H of the imidazole core may help to form supramolecular architecture through the hydrophobic-hydrophobic interaction and hydrogen bonding, respectively. Accordingly, the interfacial behavior as well as morphology of 1 in thin films were studied through a series of characterization methods such as surface pressure-area (π-A) isotherm, hysteresis analysis, ultraviolet-visible (UV-vis) absorption and steady-state fluorescence spectroscopies, Fourier transform infrared, X-ray diffraction, Brewster angle microscopy (BAM), and atomic force microscopy (AFM) measurements, and so forth. Pressure-area isotherm is an indication toward the formation of supramolecular nanostructures instead of an ideal monolayer at the air-water interface. This has been confirmed by the hysteresis analysis and BAM measurement at the air-water interface. AFM images of 1 in the LB monolayer exhibits the formation of supramolecular nanowires as well as nanorods. By controlling different film-forming parameters, it becomes possible to manipulate these nanostructures. With the passage of time, the nanowires come close to each other and become straight. Similarly, nanorods come close to each other and form bundles of several rods in the LB films. H-bonding, J-aggregation, as well as compression during film formation might play a key role in the formation of such nanostructures. Electrical switching behavior of compound 1 was also observed because of the presence of an electron donor-acceptor system in 1. This type of organic switching behavior may be promising for next-generation organic electronics.
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Affiliation(s)
| | | | - Santanu Chakraborty
- Department of Physics, NIT Agartala , Jiraniya, Agartala 799046, West Tripura, Tripura, India
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Zhou X, Cao H, Yang D, Zhang L, Jiang L, Liu M. Two-Dimensional Alignment of Self-Assembled Organic Nanotubes through Langmuir-Blodgett Technique. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:13065-13072. [PMID: 27951713 DOI: 10.1021/acs.langmuir.6b03680] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A C3-symmetric molecule was found to form organic nanotubes through supramolecular gel formation in organic solvents. These nanotubes can be dispersed in toluene without destroying the tubular nanostructures. Using the dispersions of these organic nanotubes as "spreading solutions", Langmuir-spreading films of these nanotubes were formed. Through repeated compression and expansion cycles, the nanotubes can be aligned to a certain extent. The formed Langmuir films could be subsequently transferred to a solid substrate, and the well-aligned nanotube films were constructed by Langmuir-Blodgett film deposition technique. Interestingly, many guests including polymers, water-soluble or oil-soluble organic molecules can be encapsulated into the nanotubes and further spread on a water subphase. Through elaborate control, large-scale parallel alignment of self-assembled organic nanotubes encapsulated by guests was also realized. This study implies that 2D hierarchical alignment of one-dimensional organic nanostructures can be realized using a simple method.
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Affiliation(s)
- Xiaoqin Zhou
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Hai Cao
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
| | - Dong Yang
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
| | - Li Zhang
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
| | - Long Jiang
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
| | - Minghua Liu
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering , Tianjin 300072, P. R. China
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Liu L, Zhang L, Wang T, Liu M. Interfacial assembly of amphiphilic styrylquinoxalines: alkyl chain length tunable topochemical reactions and supramolecular chirality. Phys Chem Chem Phys 2013; 15:6243-9. [DOI: 10.1039/c3cp50384d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Gopal A, Varghese R, Ajayaghosh A. Oligo(p-phenylene-ethynylene)-derived super-π-gelators with tunable emission and self-assembled polymorphic structures. Chem Asian J 2012; 7:2061-7. [PMID: 22753295 DOI: 10.1002/asia.201200410] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Indexed: 11/09/2022]
Abstract
Linear π-conjugated oligomers are known to form organogels through noncovalent interactions. Herein, we report the effect of π-repeat units on the gelation and morphological properties of three different oligo(p-phenylene-ethynylene)s: OPE3, OPE5, and OPE7. All of these molecules form fluorescent gels in nonpolar solvents at low critical gel concentrations, thereby resulting in a blue gel for OPE3, a green gel for OPE5, and a greenish yellow gel for OPE7. The molecule-molecule and molecule-substrate interactions in these OPEs are strongly influenced by the conjugation length of the molecules. Silicon wafer suppresses substrate-molecule interactions whereas a mica surface facilitates such interactions. At lower concentrations, OPE3 formed vesicular assemblies and OPE5 gave entangled fibers, whereas OPE7 resulted in spiral assemblies on a mica surface. At higher concentrations, OPE3 and OPE5 resulted in super-bundles of fibers and flowerlike short-fiber agglomerates when different conditions were applied. The number of polymorphic structures increases on increasing the conjugation length, as seen in the case of OPE7 with n=5, which resulted in a variety of exotic structures, the formation of which could be controlled by varying the substrate, concentration, and humidity.
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Affiliation(s)
- Anesh Gopal
- Photosciences and Photonics Group, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Thiruvanthapuram-695019, India
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Wan L, Li L, Mao G. Nanospiral Formation by Droplet Drying: One Molecule at a Time. NANOSCALE RESEARCH LETTERS 2011; 6:49. [PMID: 27502671 PMCID: PMC3212004 DOI: 10.1007/s11671-010-9793-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 09/09/2010] [Indexed: 06/06/2023]
Abstract
We have created nanospirals by self-assembly during droplet evaporation. The nanospirals, 60-70 nm in diameter, formed when solvent mixtures of methanol and m-cresol were used. In contrast, spin coating using only methanol as the solvent produced epitaxial films of stripe nanopatterns and using only m-cresol disordered structure. Due to the disparity in vapor pressure between the two solvents, droplets of m-cresol solution remaining on the substrate serve as templates for the self-assembly of carboxylic acid molecules, which in turn allows the visualization of solution droplet evaporation one molecule at a time.
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Affiliation(s)
- Lei Wan
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, Michigan, 48202, USA
| | - Li Li
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, Michigan, 48202, USA
| | - Guangzhao Mao
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, Michigan, 48202, USA.
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Guo P, Chen P, Liu M. Shuttle-like supramolecular nanostructures formed by self-assembly of a porphyrin via an oil/water system. NANOSCALE RESEARCH LETTERS 2011; 6:529. [PMID: 21943330 PMCID: PMC3212066 DOI: 10.1186/1556-276x-6-529] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 09/23/2011] [Indexed: 05/30/2023]
Abstract
In this paper, in terms of the concentration of an aqueous solution of a surfactant, we investigate the self-assembly behavior of a porphyrin, 5, 10, 15, 20-tetra(4-pyridyl)-21H, 23H-porphine [H2TPyP], by using an oil/water system as the medium. We find that when a chloroform solution of H2TPyP is dropwise added into an aqueous solution of cetyltrimethylammonium bromide [CTAB] with a lower concentration, a large amount of irregular nanoarchitectures, together with a small amount of well-defined shuttle-like nanostructures, hollow nanospheres, and nanotubes, could be produced. While a moderate amount of shuttle-like nanostructures accompanied by a few irregular nanoarchitectures, solid nanospheres, and nanorods are produced when a CTAB aqueous solution in moderate concentration is employed, in contrast, a great quantity of shuttle-like nanostructures together with a negligible amount of solid nanospheres, nanofibers, and irregular nanostructures are manufactured when a high-concentration CTAB aqueous solution is involved. An explanation on the basis of the molecular geometry of H2TPyP and in terms of the intermolecular π-π interactions between H2TPyP units, and hydrophobic interactions between CTAB and H2TPyP has been proposed. The investigation gives deep insights into the self-assembly behavior of porphyrins in an oil/water system and provides important clues concerning the design of appropriate porphyrins when related subjects are addressed. Our investigation suggests that an oil/aqueous system might be an efficient medium for producing unique organic-based nanostructures.
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Affiliation(s)
- Peipei Guo
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing, People's Republic of China
| | - Penglei Chen
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing, People's Republic of China
| | - Minghua Liu
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing, People's Republic of China
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Liu X, Wang T, Liu M. Interfacial assembly of cinnamoyl-terminated bolaamphiphiles through the air/water interface: headgroup-dependent assembly, supramolecular nanotube and photochemical sewing. Phys Chem Chem Phys 2011; 13:16520-9. [PMID: 21860882 DOI: 10.1039/c1cp21561b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A series of cinnamoyl-terminated bolaamphiphiles were synthesized and their assemblies at the air/water interface were investigated. It was found that the assembly behaviour depended on the substituted groups on the cinnamoyl unit. The bolaamphiphile with 4-hydroxycinnamoyl head groups (HCDA) was found to assemble into a supramolecular nanotube, while the others formed only layer-structured films. Moreover, the nanotube formed from HCDA showed supramolecular chirality due to the symmetry breaking. Both the layered films and the nanotubes showed photochemical dimerization upon UV irradiation, which were studied from the UV-Vis, FT-IR spectral and MALDI-TOF MS analysis. Interestingly, such dimerization behavior of the cinnamoyl group could be used to stabilize the nanotube of HCDAvia photochemical sewing. During such a process both the supramolecular chirality and the tubular shapes were kept. Remarkably, such a photochemical sewed chiral nanotube could further induce the chirality of an achiral porphyrin derivative assembled on it, and produced the induced chirality without using any chiral molecules.
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Affiliation(s)
- Xufei Liu
- Beijing National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, People's Republic of China
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Qiu Y, Chen P, Liu M. Interfacial assemblies of atypical amphiphilic porphyrins: hydrophobicity/hydrophilicity of substituents, annealing effects, and supramolecular chirality. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:15272-15277. [PMID: 20825152 DOI: 10.1021/la101959r] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Interfacial molecular assemblies of eight atypical amphiphilic porphyrins, substituted with hydrophobic or hydrophilic substituents but without long alkyl chains on their molecular skeletons, have been investigated in terms of supramolecular chiralty generation and amplification. It is found that all of the originally organized interfacial molecular assemblies display very weak or undetectable supramolecular chirality. Interestingly, for those porphyrins bearing hydrophilic substituents, it is found that their molecular assemblies display distinct supramolecular chirality when applying a thermal annealing treatment. In contrast, for those bearing hydrophobic substituents, the formed assemblies remain achiral after similar treatment. This investigation suggests that the hydrophobicity/hydrophilicity of the substituents of the atypical amphiphilies could affect the occurrence of the interfacial mirror symmetry breaking substantially. It discloses that, although some of the interfacial assemblies are superficially achiral, a thermal annealing treatment could endow them with evident supramolecular chirality.
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Affiliation(s)
- Yunfeng Qiu
- Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing 100190, PR China
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