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Li Z, Raab A, Kolmangadi MA, Busch M, Grunwald M, Demel F, Bertram F, Kityk AV, Schönhals A, Laschat S, Huber P. Self-Assembly of Ionic Superdiscs in Nanopores. ACS NANO 2024; 18:14414-14426. [PMID: 38760015 PMCID: PMC11155240 DOI: 10.1021/acsnano.4c01062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/23/2024] [Accepted: 05/01/2024] [Indexed: 05/19/2024]
Abstract
Discotic ionic liquid crystals (DILCs) consist of self-assembled superdiscs of cations and anions that spontaneously stack in linear columns with high one-dimensional ionic and electronic charge mobility, making them prominent model systems for functional soft matter. Compared to classical nonionic discotic liquid crystals, many liquid crystalline structures with a combination of electronic and ionic conductivity have been reported, which are of interest for separation membranes, artificial ion/proton conducting membranes, and optoelectronics. Unfortunately, a homogeneous alignment of the DILCs on the macroscale is often not achievable, which significantly limits the applicability of DILCs. Infiltration into nanoporous solid scaffolds can, in principle, overcome this drawback. However, due to the experimental challenges to scrutinize liquid crystalline order in extreme spatial confinement, little is known about the structures of DILCs in nanopores. Here, we present temperature-dependent high-resolution optical birefringence measurement and 3D reciprocal space mapping based on synchrotron X-ray scattering to investigate the thermotropic phase behavior of dopamine-based ionic liquid crystals confined in cylindrical channels of 180 nm diameter in macroscopic anodic aluminum oxide membranes. As a function of the membranes' hydrophilicity and thus the molecular anchoring to the pore walls (edge-on or face-on) and the variation of the hydrophilic-hydrophobic balance between the aromatic cores and the alkyl side chain motifs of the superdiscs by tailored chemical synthesis, we find a particularly rich phase behavior, which is not present in the bulk state. It is governed by a complex interplay of liquid crystalline elastic energies (bending and splay deformations), polar interactions, and pure geometric confinement and includes textural transitions between radial and axial alignment of the columns with respect to the long nanochannel axis. Furthermore, confinement-induced continuous order formation is observed in contrast to discontinuous first-order phase transitions, which can be quantitatively described by Landau-de Gennes free energy models for liquid crystalline order transitions in confinement. Our observations suggest that the infiltration of DILCs into nanoporous solids allows tailoring their nanoscale texture and ion channel formation and thus their electrical and optical functionalities over an even wider range than in the bulk state in a homogeneous manner on the centimeter scale as controlled by the monolithic nanoporous scaffolds.
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Affiliation(s)
- Zhuoqing Li
- Institute
for Materials and X-ray Physics, Hamburg
University of Technology, Denickestr. 15, 21073 Hamburg, Germany
- Centre
for X-ray and Nano Science CXNS, Deutsches
Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Aileen Raab
- Institut
für Organische Chemie, Universität
Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Mohamed Aejaz Kolmangadi
- Bundesanstalt
für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - Mark Busch
- Institute
for Materials and X-ray Physics, Hamburg
University of Technology, Denickestr. 15, 21073 Hamburg, Germany
- Centre
for X-ray and Nano Science CXNS, Deutsches
Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Marco Grunwald
- Institut
für Organische Chemie, Universität
Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Felix Demel
- Institut
für Organische Chemie, Universität
Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Florian Bertram
- Deutsches
Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Andriy V. Kityk
- Faculty of
Electrical Engineering, Czestochowa University
of Technology, Al. Armii
Krajowej 17, 42-200 Czestochowa, Poland
| | - Andreas Schönhals
- Bundesanstalt
für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
- Institut
für Chemie, Technische Universität
Berlin, Straße des
17. Juni 135, 10623 Berlin, Germany
| | - Sabine Laschat
- Institut
für Organische Chemie, Universität
Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Patrick Huber
- Institute
for Materials and X-ray Physics, Hamburg
University of Technology, Denickestr. 15, 21073 Hamburg, Germany
- Centre
for X-ray and Nano Science CXNS, Deutsches
Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
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2
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Jirón V, Castellón E. New method to calculate the anisotropies of polarizability and thermal expansion of uniaxial liquid crystals. J Chem Phys 2021; 154:174905. [PMID: 34241064 DOI: 10.1063/5.0049539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The anisotropy of molecular polarizability in liquid crystals is linked to the birefringence in these substances. The classic methods to compute the polarizabilities of liquid crystals assume an average number density of molecules that is equal in all directions. In the present work, a new model is proposed for the anisotropic molar polarization based on a virtual anisotropy of the number density of molecules in the liquid-crystalline material. This new strategy hence allows for the computation of both the anisotropic polarizabilities and the anisotropic thermal-expansion coefficients of liquid crystals. The model is applied to the liquid crystals 4-n-pentyl-4'-cyanobiphenyl and N-(4-methoxybenzylidene)-4-butylaniline, yielding polarizabilities similar to those reported for these materials. For these nematic liquid crystals, the results imply the existence of a positive thermal-expansion coefficient in the direction perpendicular to the director vector throughout the entire nematic temperature range and a negative thermal-expansion coefficient parallel to the director vector near the temperature of the nematic-isotropic transition. At the isotropization temperature, there exists divergent and critical behavior of the anisotropic thermal-expansion coefficients, consistent with the typical discontinuity of volume in first-order transitions.
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Affiliation(s)
- Vanessa Jirón
- Escuela de Química, Universidad de Costa Rica, San José 11501-2060, Costa Rica
| | - Erick Castellón
- Escuela de Química, Universidad de Costa Rica, San José 11501-2060, Costa Rica
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3
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Xue J, Gao Z, Xiao L. The Application of Stimuli-Sensitive Actuators Based on Graphene Materials. Front Chem 2019; 7:803. [PMID: 31921756 PMCID: PMC6914738 DOI: 10.3389/fchem.2019.00803] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/07/2019] [Indexed: 11/13/2022] Open
Abstract
Graphene-based materials that can spontaneously response to external stimulations have triggered rapidly increasing research interest for developing smart devices due to their excellent electrical, mechanical and thermal properties. The specific behaviors as bending, curling, and swing are benefit for designing and fabricating the smart actuation system. In this minireview, we overview and summarize some of the recent advancements of stimuli-responsive actuators based on graphene materials. The external stimulus usually is as electrical, electrochemical, humid, photonic, and thermal. The advancement and industrialization of graphene preparation technology would push forward the rapid progress of graphene-based actuators and broaden their application including smart sensors, robots, artificial muscles, intelligent switch, and so on.
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Affiliation(s)
| | - Zhaoshun Gao
- Interdisciplinary Research Center, Institute of Electrical Engineering, Chinese Academy of Science, Beijing, China
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4
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Wang J, Xiao Y, Cecen V, Shao C, Zhao Y, Qu L. Tunable-Deformed Graphene Layers for Actuation. Front Chem 2019; 7:725. [PMID: 31781535 PMCID: PMC6857681 DOI: 10.3389/fchem.2019.00725] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 10/10/2019] [Indexed: 11/21/2022] Open
Abstract
Benefiting from unique planar structure, high flexibility, splendid thermal, and electric properties; graphene as a crucial component has been widely applied into smart materials and multi-stimulus responsive actuators. Moreover, graphene with easy processing and modification features can be decorated with various functional groups through covalent or non-covalent bonds, which is promising in the conversion of environmental energy from single and/or multi-stimuli, to mechanical energy. In this review, we present the actuating behaviors of graphene, regulated by chemical bonds or intermolecular forces under multi-stimuli and summarize the recent advances on account of the unique nanostructures in various actuation circumstances such as thermal, humidity, electrochemical, electro-/photo-thermal, and other stimuli.
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Affiliation(s)
- Jiaqi Wang
- Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry, Beijing Institute of Technology, Beijing, China
| | - Yukun Xiao
- Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry, Beijing Institute of Technology, Beijing, China
| | - Volkan Cecen
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Changxiang Shao
- Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry, Beijing Institute of Technology, Beijing, China
| | - Yang Zhao
- Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry, Beijing Institute of Technology, Beijing, China
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Liangti Qu
- Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry, Beijing Institute of Technology, Beijing, China
- Key Laboratory for Advanced Materials Processing Technology, Ministry of Education of China, Beijing, China
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Department of Chemistry, Tsinghua University, Beijing, China
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5
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Haketa Y, Bando Y, Sasano Y, Tanaka H, Yasuda N, Hisaki I, Maeda H. Liquid Crystals Comprising π-Electronic Ions from Porphyrin-Au III Complexes. iScience 2019; 14:241-256. [PMID: 30981960 PMCID: PMC6463747 DOI: 10.1016/j.isci.2019.03.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/15/2019] [Accepted: 03/25/2019] [Indexed: 11/08/2022] Open
Abstract
Porphyrin–AuIII complexes were found to act as π-electronic cations, which can combine with various counteranions, including π-electronic anions. Single-crystal X-ray analyses revealed the formation of assemblies with contributions of charge-by-charge and charge-segregated assemblies, depending on the geometry and electronic state of the counteranions. Porphyrin–AuIII complexes possessing aliphatic alkyl chains formed dimension-controlled ion-pairing assemblies as thermotropic liquid crystals, whose ionic components were highly organized by π–π stacking and electrostatic interactions. Ion pairs based on porphyrin–AuIII complexes as π-electronic cations were prepared Porphyrin–AuIII complexes formed ion-pairing assemblies in combination with anions Aliphatic substituents in the cations provided liquid crystalline mesophases
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Affiliation(s)
- Yohei Haketa
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Yuya Bando
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Yoshifumi Sasano
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Hiroki Tanaka
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Nobuhiro Yasuda
- Research and Utilization Division, Japan Synchrotron Radiation Research Institute, Sayo 679-5198, Japan
| | - Ichiro Hisaki
- Green Nanotechnology Research Center, Research Institute for Electronic Science, Hokkaido University, Sapporo 001-0020, Japan
| | - Hiromitsu Maeda
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, Kusatsu 525-8577, Japan.
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6
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Pipertzis A, Zardalidis G, Wunderlich K, Klapper M, Müllen K, Floudas G. Ionic Conduction in Poly(ethylene glycol)-Functionalized Hexa-peri-hexabenzocoronene Amphiphiles. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00224] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Achilleas Pipertzis
- Department
of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
| | - George Zardalidis
- Department
of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
| | | | - Markus Klapper
- Max Planck Institute
for Polymer Research, 55128 Mainz, Germany
| | - Klaus Müllen
- Max Planck Institute
for Polymer Research, 55128 Mainz, Germany
| | - George Floudas
- Department
of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
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7
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Sivadas AP, Rao DSS, Kumar NSS, Prabhu DD, Varghese S, Ramachandran CN, Ongungal RM, Krishna Prasad S, Das S. Self-Assembling and Luminescent Properties of Chiral Bisoxadiazole Derivatives in Solution and Liquid-Crystalline Phases. J Phys Chem B 2017; 121:1922-1929. [PMID: 28170256 DOI: 10.1021/acs.jpcb.6b09820] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Herein, we report the synthesis, self-assembly, and electroluminescence characteristics of a new green-emitting, pseudodiscoid chiral molecule, OXDC, containing an electron-donating stilbene core and an electron-accepting oxadiazole substituent. The helical organization and specific interaction of the chiral pseudodiscoid molecule resulted in the formation of self-assembled nanofibers with a columnar superstructure. Macroscopic chirality was observed in both the liquid-crystalline phases and the self-assembled nanofibers of OXDC, a feature which was absent in the analogous achiral oxadiazole derivative reported earlier [ Sivadas , A. P. ; Supergelation via Purely Aromatic π-π Driven Self-Assembly of Pseudodiscotic Oxadiazole Mesogens . J. Am. Chem. Soc. 2014 , 136 , 5416 - 5423 ]. A high-performance organic light-emitting device was demonstrated using OXDC as the emitting material, with a luminous intensity of 10 115 cd m-2 at 5 V and chromaticity coordinates of (0.32, 0.51).
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Affiliation(s)
- Aneesh P Sivadas
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) and Network of Institutes for Solar Energy, CSIR , Trivandrum 695019, India
| | - D S Shankar Rao
- Centre for Nano and Soft Matter Sciences , Jalahalli, Bangalore 560013, India
| | - N S Saleesh Kumar
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) and Network of Institutes for Solar Energy, CSIR , Trivandrum 695019, India
| | - Deepak D Prabhu
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) and Network of Institutes for Solar Energy, CSIR , Trivandrum 695019, India
| | - Shinto Varghese
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) and Network of Institutes for Solar Energy, CSIR , Trivandrum 695019, India
| | - C N Ramachandran
- Department of Chemistry, Indian Institute of Technology Roorkee , Roorkee, Uttarakhand 247667, India
| | - Rahul M Ongungal
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) and Network of Institutes for Solar Energy, CSIR , Trivandrum 695019, India.,Academy of Scientific and Innovative Research (AcSIR), CSIR-NIIST , Trivandrum 695019, India
| | - S Krishna Prasad
- Centre for Nano and Soft Matter Sciences , Jalahalli, Bangalore 560013, India
| | - Suresh Das
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) and Network of Institutes for Solar Energy, CSIR , Trivandrum 695019, India.,Kerala State Council for Science Technology and Environment , Sasthra Bhavan, Pattom, Trivandrum 695004, India.,Academy of Scientific and Innovative Research (AcSIR), CSIR-NIIST , Trivandrum 695019, India
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8
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Xiao P, Yi N, Zhang T, Huang Y, Chang H, Yang Y, Zhou Y, Chen Y. Construction of a Fish-like Robot Based on High Performance Graphene/PVDF Bimorph Actuation Materials. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2016; 3:1500438. [PMID: 27818900 PMCID: PMC5071709 DOI: 10.1002/advs.201500438] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 01/27/2016] [Indexed: 05/20/2023]
Abstract
Smart actuators have many potential applications in various areas, so the development of novel actuation materials, with facile fabricating methods and excellent performances, are still urgent needs. In this work, a novel electromechanical bimorph actuator constituted by a graphene layer and a PVDF layer, is fabricated through a simple yet versatile solution approach. The bimorph actuator can deflect toward the graphene side under electrical stimulus, due to the differences in coefficient of thermal expansion between the two layers and the converse piezoelectric effect and electrostrictive property of the PVDF layer. Under low voltage stimulus, the actuator (length: 20 mm, width: 3 mm) can generate large actuation motion with a maximum deflection of about 14.0 mm within 0.262 s and produce high actuation stress (more than 312.7 MPa/g). The bimorph actuator also can display reversible swing behavior with long cycle life under high frequencies. on this basis, a fish-like robot that can swim at the speed of 5.02 mm/s is designed and demonstrated. The designed graphene-PVDF bimorph actuator exhibits the overall novel performance compared with many other electromechanical avtuators, and may contribute to the practical actuation applications of graphene-based materials at a macro scale.
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Affiliation(s)
- Peishuang Xiao
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Ningbo Yi
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Tengfei Zhang
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Yi Huang
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Huicong Chang
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Yang Yang
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Ying Zhou
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
| | - Yongsheng Chen
- Centre for Nanoscale Science and Technology Key Laboratory of Functional Polymer Materials Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Materials Science and Engineering Nankai University Tianjin 300071 P.R. China
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9
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Wöhrle T, Wurzbach I, Kirres J, Kostidou A, Kapernaum N, Litterscheidt J, Haenle JC, Staffeld P, Baro A, Giesselmann F, Laschat S. Discotic Liquid Crystals. Chem Rev 2015; 116:1139-241. [PMID: 26483267 DOI: 10.1021/acs.chemrev.5b00190] [Citation(s) in RCA: 422] [Impact Index Per Article: 46.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tobias Wöhrle
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Iris Wurzbach
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Jochen Kirres
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Antonia Kostidou
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Nadia Kapernaum
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Juri Litterscheidt
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Johannes Christian Haenle
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Peter Staffeld
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Angelika Baro
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Frank Giesselmann
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Sabine Laschat
- Institut für Organische Chemie, and ‡Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart, Germany
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10
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Yadav N, Kumar S, Dhar R. Cadmium selenide quantum dots for the amelioration of the properties of a room temperature discotic liquid crystalline material. RSC Adv 2015. [DOI: 10.1039/c5ra17401e] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The effect of cadmium selenide quantum dots on a room temperature discotic liquid crystalline material has been studied.
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Affiliation(s)
- Neelam Yadav
- Centre of Material Sciences
- University of Allahabad
- Allahabad 211002
- India
| | | | - Ravindra Dhar
- Centre of Material Sciences
- University of Allahabad
- Allahabad 211002
- India
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11
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Hu Y, Lan T, Wu G, Zhu Z, Chen W. A spongy graphene based bimorph actuator with ultra-large displacement towards biomimetic application. NANOSCALE 2014; 6:12703-12709. [PMID: 25220910 DOI: 10.1039/c4nr02768j] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bimorph actuators, consisting of two layers with asymmetric expansion and generating bending displacement, have been widely researched. Their actuation performances greatly rely on the difference of coefficients of thermal expansion (CTE) between the two material layers. Here, by introducing a spongy graphene (sG) paper with a large negative CTE as well as high electrical-to-thermal properties, an electromechanical sG/PDMS bimorph actuator is designed and fabricated, showing an ultra-large bending displacement output under low voltage stimulation (curvature of about 1.2 cm(-1) at 10 V for 3 s), a high displacement-to-length ratio (∼0.79), and vibration motion at AC voltage (up to 10 Hz), which is much larger and faster than that of the other electromechanical bimorph actuators. Based on the sG/PDMS bimorph serving as the "finger", a mechanical gripper is constructed to realize the fast manipulation of the objects under 0.1 Hz square wave voltage stimulation (0-8 V). The designed bimorph actuator coupled with ultra-large bending displacement, low driven voltage, and the ease of fabrication may open up substantial possibilities for the utilization of electromechanical actuators in practical biomimetic device applications.
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Affiliation(s)
- Ying Hu
- i-Lab, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou, 215123, P. R. China.
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12
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Krause C, Zorn R, Frick B, Schönhals A. Thermal properties and vibrational density of states of a nanoconfined discotic liquid crystal. Colloid Polym Sci 2014. [DOI: 10.1007/s00396-014-3247-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Effectively control negative thermal expansion of single-phase ferroelectrics of PbTiO3-(Bi,La)FeO3 over a giant range. Sci Rep 2014; 3:2458. [PMID: 23949238 PMCID: PMC3744799 DOI: 10.1038/srep02458] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 07/31/2013] [Indexed: 11/18/2022] Open
Abstract
Control of negative thermal expansion is a fundamentally interesting topic in the negative thermal expansion materials in order for the future applications. However, it is a challenge to control the negative thermal expansion in individual pure materials over a large scale. Here, we report an effective way to control the coefficient of thermal expansion from a giant negative to a near zero thermal expansion by means of adjusting the spontaneous volume ferroelectrostriction (SVFS) in the system of PbTiO3-(Bi,La)FeO3 ferroelectrics. The adjustable range of thermal expansion contains most negative thermal expansion materials. The abnormal property of negative or zero thermal expansion previously observed in ferroelectrics is well understood according to the present new concept of spontaneous volume ferroelectrostriction. The present studies could be useful to control of thermal expansion of ferroelectrics, and could be extended to multiferroic materials whose properties of both ferroelectricity and magnetism are coupled with thermal expansion.
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14
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Krause C, Zorn R, Emmerling F, Falkenhagen J, Frick B, Huber P, Schönhals A. Vibrational density of states of triphenylene based discotic liquid crystals: dependence on the length of the alkyl chain. Phys Chem Chem Phys 2014; 16:7324-33. [DOI: 10.1039/c3cp55303e] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Picco AS, Zelaya E, Azzaroni O, Ceolín M. Supramacromolecular organization of gold nanocrystals capped with amphiphilic hyperbranched polyethyleneimine. J Colloid Interface Sci 2013; 397:206-9. [DOI: 10.1016/j.jcis.2013.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 12/28/2012] [Accepted: 01/01/2013] [Indexed: 10/27/2022]
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16
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Duran H, Hartmann-Azanza B, Steinhart M, Gehrig D, Laquai F, Feng X, Müllen K, Butt HJ, Floudas G. Arrays of aligned supramolecular wires by macroscopic orientation of columnar discotic mesophases. ACS NANO 2012; 6:9359-9365. [PMID: 23102401 DOI: 10.1021/nn302937t] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Structure formation, phase behavior, and dynamics of mono-bromo hexa-peri-hexabenzocoronene (HBC-Br) are strongly affected by the confinement of cylindrical nanopores with rigid walls. Using self-ordered nanoporous anodic aluminum oxide (AAO)-containing arrays of aligned nanopores with narrow size distribution as a confining matrix, pronounced alignment of the HBC-Br columns along the nanopore axes was found to be independent of the pore diameter. Hence, arrays of one-dimensional supramolecular HBC-Br wires with the columns uniformly oriented along the wire axes on a macroscopic scale were obtained, unlike with discotics bearing smaller cores. The formation of the crystalline herringbone structure is shifted to lower temperatures in nanopores with diameters of a few hundred nanometers, whereas the formation of this low-temperature phase is completely suppressed when the pore diameter is below 20 lattice parameters. Moreover, the cylindrical confinement affects the disk axial dynamics as well as the distribution of relaxation times.
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Affiliation(s)
- Hatice Duran
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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17
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Zhu J, Andres CM, Xu J, Ramamoorthy A, Tsotsis T, Kotov NA. Pseudonegative thermal expansion and the state of water in graphene oxide layered assemblies. ACS NANO 2012; 6:8357-8365. [PMID: 22861527 DOI: 10.1021/nn3031244] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Unraveling the complex interplay between thermal properties and hydration is a part of understanding the fundamental properties of many soft materials and very essential for many applications. Here we show that graphene oxide (GO) demonstrates a highly negative thermal expansion (NTE) coefficient owing to unique thermohydration processes related with fast transport of water between the GO sheets, the amphiphilic nature of nanochannels, and close-to-zero intrinsic thermal expansion of GO. The humidity-dependent NTE of GO layered assemblies, or "pseudonegative thermal expansion" (PNTE), differs from that of other hygroscopic materials due to its relatively fast and highly reversible expansion/contraction cycles and occurrence at low humidity levels while bearing similarities to classic NTE. Thermal expansion of polyvinyl alcohol/GO composites is easily tunable with additional intricacy of thermohydration effects. PNTE combined with isotropy, nontoxicity, and mechanical robustness is an asset for applications of actuators, sensors, MEMS devices, and memory materials and crucial for developing methods of thermal/photopatterning of GO devices.
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Affiliation(s)
- Jian Zhu
- Department of Chemical Engineering, University of Michigan, Ann Arbor 48109, United States
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18
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Abstract
Polycyclic aromatic hydrocarbons (PAHs) are in a class of functional organic compounds with increasing importance in organic electronics. Their tunable photophysical properties and typically strong intermolecular associations make them ideal materials in applications where control of charge mobility is essential. Hexa-peri-hexabenzocoronene (HBC) is a disc-shaped PAH that self-associates into columnar stacks through strong π–π interactions. By decorating the periphery of the HBC molecule with various substituents, a range of properties and functions can be obtained including solution processability, liquid crystallinity, and semiconductivity. In this review article, the synthesis, properties, and functions of HBC derivatives are presented with focus on work published in the last five years.
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19
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Papadopoulos P, Grigoriadis C, Haase N, Butt HJ, Müllen K, Floudas G. Dynamics of Structure Formation in a Discotic Liquid Crystal by Infrared Spectroscopy and Related Techniques. J Phys Chem B 2011; 115:14919-27. [DOI: 10.1021/jp207410f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Christos Grigoriadis
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI)
| | - Nino Haase
- Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | | | - Klaus Müllen
- Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - George Floudas
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI)
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20
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Haase N, Grigoriadis C, Butt HJ, Müllen K, Floudas G. Effect of Dipole Functionalization on the Thermodynamics and Dynamics of Discotic Liquid Crystals. J Phys Chem B 2011; 115:5807-14. [DOI: 10.1021/jp201552h] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nino Haase
- Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Christos Grigoriadis
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas, Biomedical Research Institute (FORTH-BRI), Ioannina, Greece
| | | | - Klaus Müllen
- Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - George Floudas
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas, Biomedical Research Institute (FORTH-BRI), Ioannina, Greece
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21
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Picco AS, Yameen B, Azzaroni O, Ceolín M. Thermoreversible formation and negative thermal expansion of supramacromolecular assemblies of unimolecular micelles in solution. Chem Commun (Camb) 2011; 47:3802-4. [DOI: 10.1039/c0cc05472k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Chen CW, Chang HY, Lee SL, Hsu IJ, Lee JJ, Chen CH, Luh TY. Hexa-peri-hexabenzocoronene (HBC)-Incorporated Single- and Double-Stranded Polynorbornenes. Macromolecules 2010. [DOI: 10.1021/ma101956n] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chih-Wei Chen
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - Hong-Yi Chang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - Shern-Long Lee
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - I-Jui Hsu
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, Taiwan 106
| | - Jey-Jau Lee
- National Synchrotron Radiation Research Center, Hsinchu, Taiwan 30076
| | - Chun-hsien Chen
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - Tien-Yau Luh
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106
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23
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Tasios N, Grigoriadis C, Hansen MR, Wonneberger H, Li C, Spiess HW, Müllen K, Floudas G. Self-Assembly, Dynamics, and Phase Transformation Kinetics of Donor−Acceptor Substituted Perylene Derivatives. J Am Chem Soc 2010; 132:7478-87. [DOI: 10.1021/ja102150g] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Nikos Tasios
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Christos Grigoriadis
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Michael Ryan Hansen
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Henrike Wonneberger
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Chen Li
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Hans W. Spiess
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Klaus Müllen
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - George Floudas
- Department of Physics, University of Ioannina, 451 10 Ioannina, Greece and Foundation for Research and Technology-Hellas (FORTH-BRI), and Max-Planck Institute for Polymer Research, 55128 Mainz, Germany
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