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Díaz D, Nickel O, Moraga N, Catalán RE, Retamal MJ, Zelada H, Cisternas M, Meißner R, Huber P, Corrales TP, Volkmann UG. How water wets and self-hydrophilizes nanopatterns of physisorbed hydrocarbons. J Colloid Interface Sci 2021; 606:57-66. [PMID: 34388573 DOI: 10.1016/j.jcis.2021.07.121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 07/22/2021] [Accepted: 07/23/2021] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Weakly bound, physisorbed hydrocarbons could in principle provide a similar water-repellency as obtained by chemisorption of strongly bound hydrophobic molecules at surfaces. EXPERIMENTS Here we present experiments and computer simulations on the wetting behaviour of water on molecularly thin, self-assembled alkane carpets of dotriacontane (n-C32H66 or C32) physisorbed on the hydrophilic native oxide layer of silicon surfaces during dip-coating from a binary alkane solution. By changing the dip-coating velocity we control the initial C32 surface coverage and achieve distinct film morphologies, encompassing homogeneous coatings with self-organised nanopatterns that range from dendritic nano-islands to stripes. FINDINGS These patterns exhibit a good water wettability even though the carpets are initially prepared with a high coverage of hydrophobic alkane molecules. Using in-liquid atomic force microscopy, along with molecular dynamics simulations, we trace this to a rearrangement of the alkane layers upon contact with water. This restructuring is correlated to the morphology of the C32 coatings, i.e. their fractal dimension. Water molecules displace to a large extent the first adsorbed alkane monolayer and thereby reduce the hydrophobic C32 surface coverage. Thus, our experiments evidence that water molecules can very effectively hydrophilize initially hydrophobic surfaces that consist of weakly bound hydrocarbon carpets.
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Affiliation(s)
- Diego Díaz
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
| | - Ole Nickel
- Hamburg University of Technology, Institute of Polymers and Composites, 21073 Hamburg, Germany
| | - Nicolás Moraga
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Rodrigo E Catalán
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - María José Retamal
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Hugo Zelada
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Marcelo Cisternas
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Robert Meißner
- Hamburg University of Technology, Institute of Polymers and Composites, 21073 Hamburg, Germany; Helmholtz-Zentrum Hereon, Institute of Surface Science, 21494 Geesthacht, Germany
| | - Patrick Huber
- Hamburg University of Technology, Institute for Materials and X-Ray Physics, 21073 Hamburg, Germany; Deutsches Elektronen-Synchrotron DESY, Centre for X-Ray and Nano Science CXNS, 22603 Hamburg, Germany; University of Hamburg, Centre for Hybrid Nanostructures CHyN, 22607 Hamburg, Germany.
| | - Tomas P Corrales
- Departamento de Física, Universidad Técnica Federico Santa María, Valparaiso 2390123, Chile.
| | - Ulrich G Volkmann
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; Centro de Investigación en Nanotecnología y Materiales Avanzados (CIEN-UC), Pontificia Universidad Católica de Chile, Santiago 7820436, Chile.
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Cisternas MA, Palacios-Coddou F, Molina S, Retamal MJ, Gomez-Vierling N, Moraga N, Zelada H, Soto-Arriaza MA, Corrales TP, Volkmann UG. Dry Two-Step Self-Assembly of Stable Supported Lipid Bilayers on Silicon Substrates. Int J Mol Sci 2020; 21:E6819. [PMID: 32957654 PMCID: PMC7555443 DOI: 10.3390/ijms21186819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/13/2020] [Accepted: 09/16/2020] [Indexed: 11/17/2022] Open
Abstract
Artificial membranes are models for biological systems and are important for applications. We introduce a dry two-step self-assembly method consisting of the high-vacuum evaporation of phospholipid molecules over silicon, followed by a subsequent annealing step in air. We evaporate dipalmitoylphosphatidylcholine (DPPC) molecules over bare silicon without the use of polymer cushions or solvents. High-resolution ellipsometry and AFM temperature-dependent measurements are performed in air to detect the characteristic phase transitions of DPPC bilayers. Complementary AFM force-spectroscopy breakthrough events are induced to detect single- and multi-bilayer formation. These combined experimental methods confirm the formation of stable non-hydrated supported lipid bilayers with phase transitions gel to ripple at 311.5 ± 0.9 K, ripple to liquid crystalline at 323.8 ± 2.5 K and liquid crystalline to fluid disordered at 330.4 ± 0.9 K, consistent with such structures reported in wet environments. We find that the AFM tip induces a restructuring or intercalation of the bilayer that is strongly related to the applied tip-force. These dry supported lipid bilayers show long-term stability. These findings are relevant for the development of functional biointerfaces, specifically for fabrication of biosensors and membrane protein platforms. The observed stability is relevant in the context of lifetimes of systems protected by bilayers in dry environments.
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Affiliation(s)
- Marcelo A. Cisternas
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Francisca Palacios-Coddou
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Sebastian Molina
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Maria Jose Retamal
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
- Departamento de Química-Física, Facultad de Quimica y de Farmacia, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile
| | - Nancy Gomez-Vierling
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Nicolas Moraga
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Hugo Zelada
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Marco A. Soto-Arriaza
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
- Departamento de Química-Física, Facultad de Quimica y de Farmacia, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile
| | - Tomas P. Corrales
- Departamento de Fisica, Universidad Técnica Federico Santa María, Valparaíso 2390123, Chile;
| | - Ulrich G. Volkmann
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
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Accessing the structural and thermodynamic properties of ultra-thin layers of C32 adsorbed on a SiO 2 surface. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.01.065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Corrales TP, Bai M, del Campo V, Homm P, Ferrari P, Diama A, Wagner C, Taub H, Knorr K, Deutsch M, Retamal MJ, Volkmann UG, Huber P. Spontaneous formation of nanopatterns in velocity-dependent dip-coated organic films: from dragonflies to stripes. ACS NANO 2014; 8:9954-9963. [PMID: 25188291 DOI: 10.1021/nn5014534] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present an experimental study of the micro- and mesoscopic structure of thin films of medium length n-alkane molecules on the native oxide layer of a silicon surface, prepared by dip-coating in a n-C32H66/n-heptane solution. Electron micrographs reveal two distinct adsorption morphologies depending on the substrate withdrawal speed v. For small v, dragonfly-shaped molecular islands are observed. For a large v, stripes parallel to the withdrawal direction are observed. These have lengths of a few hundred micrometers and a few micrometer lateral separation. For a constant v, the stripes' quality and separation increase with the solution concentration. Grazing incidence X-ray diffraction and atomic force microscopy show that both patterns are 4.2 nm thick monolayers of fully extended, surface-normal-aligned alkane molecules. With increasing v, the surface coverage first decreases then increases for v > v(cr) ∼ 0.15 mm/s. The critical v(cr) marks a transition between the evaporation regime, where the solvent's meniscus remains at the bulk's surface, and the entrainment (Landau-Levich-Deryaguin) regime, where the solution is partially dragged by the substrate, covering the withdrawn substrate by a homogeneous film. The dragonflies are single crystals with habits determined by dendritic growth in prominent 2D crystalline directions of randomly seeded nuclei assumed to be quasi-hexagonal. The stripes' strong crystalline texture and the well-defined separation are due to an anisotropic 2D crystallization in narrow liquid fingers, which result from a Marangoni flow driven hydrodynamic instability in the evaporating dip-coated films, akin to the tears of wine phenomenology.
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Affiliation(s)
- Tomas P Corrales
- Facultad de Física, Pontificia Universidad Católica de Chile , 7820436 Santiago, Chile
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Samith VD, Miño G, Ramos-Moore E, Arancibia-Miranda N. Effects of pluronic F68 micellization on the viability of neuronal cells in culture. J Appl Polym Sci 2013. [DOI: 10.1002/app.39426] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Vicente D. Samith
- Universidad Andres Bello, Departamento de Química, Facultad de Ciencias Exactas; Av. República 275, 3er piso; Santiago; Chile
| | - Germán Miño
- Group of NanoMaterials, Departamento de Física; Facultad de Ciencias, Universidad de Chile; Casilla 653; Santiago; Chile
| | - E. Ramos-Moore
- Departamento de Física; Pontificia Universidad Católica de Chile; Santiago; 7820436; Chile
| | - Nicolás Arancibia-Miranda
- Facultad de Química y Biología, CEDENNA; Universidad de Santiago de Chile, USACH; Casilla 40, C.P. 33; Santiago; Chile
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González H C, Volkmann UG, Retamal MJ, Cisternas M, Sarabia MA, López KA. Thermal behavior of 1,2-dipalmitoyl-sn-3-phosphoglycerocholine bi- and multi-layers, deposited with physical vapor deposition under ellipsometric growth control. J Chem Phys 2012; 136:134709. [PMID: 22482582 DOI: 10.1063/1.3698486] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
1,2-dipalmitoyl-sn-3-phosphoglycerocholine membranes were deposited onto a silicon substrate (Si/SiO(2)) using physical vapor deposition with in situ ellipsometric thickness control. Along several heating cycles it was possible to identify well-defined boundaries for gel, ripple, liquid crystalline, and fluid-disordered phases. Particularly, the second order transition between gel and ripple phase was clearly identified in the range of ~28-34 °C using Raman spectroscopy. Atomic force microscopy and imaging ellipsometry (IE) were used to observe and characterize the ripple phase undulations of period λ = 20.8 nm and average height h = 19.95 nm along the temperature interval of ~34 to 40 °C. Clusters/agglomerations heights of more than twice the membrane thickness were observed with IE, induced by heating cycles.
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Affiliation(s)
- Carmen González H
- Facultad de Física, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860-Santiago, 7820436 Chile.
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Lu L, Cai Y. Molecular tilting and its impact on frictional properties of n-alkane self-assembled monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:5953-5960. [PMID: 21488616 DOI: 10.1021/la105072x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Hydrophobic, methyl-terminated self-assembled monolayer (SAM) surfaces can be used to reduce friction. Among methyl-terminated SAMs, the frictional properties of alkanethiol SAMs and silane SAMs have been well-studied. In this research, we investigated friction of methyl-terminated n-hexatriacontane (C36) SAM and compared its friction properties with the alkanethiol and silane SAMs. Alkane SAM does not have an anchoring group. The alkane molecules stand on the surface by physical adsorption, which leads to a higher surface mobility of alkane molecules. We found that C36 SAM has a higher coefficient of friction than that of octadecyltrichlorosilane (OTS) silane. When an atomic force microscope (AFM) tip was swiped across the alkane SAM with a loading force, we found that the alkane SAM can withstand the tip loading pressure up to 0.48 GPa. Between 0.48 and 0.49Ga, the AFM tip partially penetrated the SAM. When the tip moved away, the deformed SAM healed and maintained the structural integrity. When the loading pressure was higher than 0.49 GPa, the alkane SAM was shaved into small pieces by the tip. In addition, we found that the molecular tilting of C36 molecules interacted with the tribological properties of the alkane SAM surface. On one hand, a higher loading force can push the rod-like alkane molecules to a higher tilting angle; on the other hand, a higher molecular tilting leads to a lower friction surface.
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Affiliation(s)
- Lingbo Lu
- Department of Chemistry, University of Kentucky, 505 Rose Street, Lexington, Kentucky 40506, United States
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Palomaki PKB, Krawicz A, Dinolfo PH. Thickness, surface morphology, and optical properties of porphyrin multilayer thin films assembled on Si(100) using copper(I)-catalyzed azide-alkyne cycloaddition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:4613-4622. [PMID: 21410232 DOI: 10.1021/la104499b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report the structure, optical properties and surface morphology of Si(100) supported molecular multilayers resulting from a layer-by-layer (LbL) fabrication method utilizing copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC), also known as "click" chemistry. Molecular based multilayer films comprised of 5,10,15,20-tetra(4-ethynylphenyl)porphyrinzinc(II) (1) and either 1,3,5-tris(azidomethyl)benzene (2) or 4,4'-diazido-2,2'-stilbenedisulfonic acid disodium salt (3) as a linker layer, displayed linear growth properties up to 19 bilayers. With a high degree of linearity, specular X-ray reflectivity (XRR) measurements yield an average thickness of 1.87 nm/bilayer for multilayers of 1 and 2 and 2.41 nm/bilayer for multilayers of 1 and 3. Surface roughnesses as determined by XRR data fitting were found to increase with the number of layers and generally were around 12% of the film thickness. Tapping mode AFM measurements confirm the continuous nature of the thin films with roughness values slightly larger than those determined from XRR. Spectroscopic ellipsometry measurements utilizing a Cauchy model mirror the XRR data for multilayer growth but with a slightly higher thickness per bilayer. Modeling of the ellipsometric data over the full visible region using an oscillator model produces an absorption profile closely resembling that of a multilayer grown on silica glass. Comparing intramolecular distances from DFT modeling with experimental film thicknesses, the average molecular growth angles were estimated between 40° and 70° with respect to the substrate surface depending on the bonding configuration.
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Affiliation(s)
- Peter K B Palomaki
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
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Lu L, Zander KJ, Cai Y. Stability of the parallel layer during alkane spreading and the domain structures of the standing-up layer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:5624-5631. [PMID: 20297777 DOI: 10.1021/la904387d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The spreading of liquid alkanes over surfaces plays an important role in applications such as lubrication, painting, and printing. To make significant advances in these fields, it is essential to increase our understanding of the interactions between alkanes and surfaces. Long-chain alkanes form two typical adsorption structures on a surface--the parallel phase and the standing-up phase. The most thermodynamically stable structure is the parallel phase, in which the alkane molecules lie flat on the surface. If the temperature is slightly below the bulk melting point, then alkanes form a thermodynamically stable standing-up phase on top of an existing parallel layer. At lower temperatures, the standing-up phase becomes metastable. Using atomic force microscopy, we have found that the standing-up alkane layer consists of multiple domains, indicating that the standing-up layer forms through a multinucleation process during the liquid-solid transition on the surface. If, however, the temperature is above the melting point, then we have found that the standing-up layer shrinks to a droplet and leaves a residue on its original position. During the spreading of an alkane droplet, the parallel layer forms on the substrate surface surrounding the droplet by adsorption from the vapor, which precedes the arrival of the liquid. There has been uncertainty, however, as to whether the parallel layer moves with the liquid alkane or remains stationary during spreading. In this study, we used the residue left on the parallel layer as a landmark to monitor the movement of the parallel layer during the spreading of an alkane droplet. Using this landmark, we found that the parallel layer remained stationary on the substrate, indicating that the liquid alkane spreads on a stationary parallel layer surface. Therefore, this study reveals that the surface properties of the parallel layer--not the surface properties of the substrate--control the spreading and wetting of a liquid alkane.
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Affiliation(s)
- Lingbo Lu
- Department of Chemistry, University of Kentucky, 505 Rose Street, Lexington, Kentucky 40506, USA
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Jiang K, Xie B, Fu D, Luo F, Liu G, Su Y, Wang D. Solid−Solid Phase Transition of n-Alkanes in Multiple Nanoscale Confinement. J Phys Chem B 2009; 114:1388-92. [DOI: 10.1021/jp9111475] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kai Jiang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Baoquan Xie
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Dongsheng Fu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Faliang Luo
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Guoming Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Yunlan Su
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Dujin Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China, and Graduate School of Chinese Academy of Sciences, Beijing 100190, P. R. China
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