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Li X, Ou X, Chen G, Bi R, Li Z, Xie Z, Yue W, Guo SZ. Ultrasoft and High-Adhesion Block Copolymers for Neuromorphic Computing. ACS APPLIED MATERIALS & INTERFACES 2024. [PMID: 38412379 DOI: 10.1021/acsami.3c19350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
The "von Neumann bottleneck" is a formidable challenge in conventional computing, driving exploration into artificial synapses. Organic semiconductor materials show promise but are hindered by issues such as poor adhesion and a high elastic modulus. Here, we combine polyisoindigo-bithiophene (PIID-2T) with grafted poly(dimethylsiloxane) (PDMS) to synthesize the triblock-conjugated polymer (PIID-2T-PDMS). The polymer exhibited substantial enhancements in adhesion (4.8-68.8 nN) and reductions in elastic modulus (1.6-0.58 GPa) while maintaining the electrical characteristics of PIID-2T. The three-terminal organic synaptic transistor (three-terminal p-type organic artificial synapse (TPOAS)), constructed using PIID-2T-PDMS, exhibits an unprecedented analog switching range of 276×, surpassing previous records, and a remarkable memory on-off ratio of 106. Moreover, the device displays outstanding operational stability, retaining 99.6% of its original current after 1600 write-read events in the air. Notably, TPOAS replicates key biological synaptic behaviors, including paired-pulse facilitation (PPF), short-term plasticity (STP), and long-term plasticity (LTP). Simulations using handwritten digital data sets reveal an impressive recognition accuracy of 91.7%. This study presents a polyisoindigo-bithiophene-based block copolymer that offers enhanced adhesion, reduced elastic modulus, and high-performance artificial synapses, paving the way for the next generation of neuromorphic computing systems.
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Affiliation(s)
- Xiaohong Li
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Xingcheng Ou
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Guoliang Chen
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Ran Bi
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Ziqian Li
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Zhuang Xie
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Wan Yue
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Shuang-Zhuang Guo
- Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China
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Reynoud N, Geneix N, D'Orlando A, Petit J, Mathurin J, Deniset-Besseau A, Marion D, Rothan C, Lahaye M, Bakan B. Cuticle architecture and mechanical properties: a functional relationship delineated through correlated multimodal imaging. THE NEW PHYTOLOGIST 2023; 238:2033-2046. [PMID: 36869436 DOI: 10.1111/nph.18862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 02/27/2023] [Indexed: 05/04/2023]
Abstract
Cuticles are multifunctional hydrophobic biocomposites that protect the aerial organs of plants. During plant development, plant cuticles must accommodate different mechanical constraints combining extensibility and stiffness, and the corresponding relationships with their architecture are unknown. Recent data showed a fine-tuning of cuticle architecture during fruit development, with several chemical clusters which raise the question of how they impact the mechanical properties of cuticles. We investigated the in-depth nanomechanical properties of tomato (Solanum lycopersicum) fruit cuticle from early development to ripening, in relation to chemical and structural heterogeneities by developing a correlative multimodal imaging approach. Unprecedented sharps heterogeneities were evidenced including an in-depth mechanical gradient and a 'soft' central furrow that were maintained throughout the plant development despite the overall increase in elastic modulus. In addition, we demonstrated that these local mechanical areas are correlated to chemical and structural gradients. This study shed light on fine-tuning of mechanical properties of cuticles through the modulation of their architecture, providing new insight for our understanding of structure-function relationships of plant cuticles and for the design of bioinspired material.
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Affiliation(s)
- Nicolas Reynoud
- INRAE, Unité Biopolymères, Interactions, Assemblages, BP71627, 44316, Nantes Cedex3, France
| | - Nathalie Geneix
- INRAE, Unité Biopolymères, Interactions, Assemblages, BP71627, 44316, Nantes Cedex3, France
| | - Angelina D'Orlando
- INRAE, Unité Biopolymères, Interactions, Assemblages, BP71627, 44316, Nantes Cedex3, France
- INRAE PROBE Research Infrastructure, BIBS Facility, F-44300, Nantes, France
| | - Johann Petit
- INRAE, Univ. Bordeaux, UMR BFP, F-33140, Villenave d'Ornon, France
| | - Jeremie Mathurin
- Institut de Chimie Physique, UMR8000, Université Paris-Saclay, CNRS, 91405, Orsay, France
| | - Ariane Deniset-Besseau
- Institut de Chimie Physique, UMR8000, Université Paris-Saclay, CNRS, 91405, Orsay, France
| | - Didier Marion
- INRAE, Unité Biopolymères, Interactions, Assemblages, BP71627, 44316, Nantes Cedex3, France
| | | | - Marc Lahaye
- INRAE, Unité Biopolymères, Interactions, Assemblages, BP71627, 44316, Nantes Cedex3, France
| | - Bénédicte Bakan
- INRAE, Unité Biopolymères, Interactions, Assemblages, BP71627, 44316, Nantes Cedex3, France
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Stoica I, Barzic AI, Ursu C, Stoian G, Hitruc EG, Sava I. Atomic Force Microscopy Probing and Analysis of Polyimide Supramolecular Systems for Sensor Devices. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23094489. [PMID: 37177692 PMCID: PMC10181602 DOI: 10.3390/s23094489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 05/02/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023]
Abstract
A series of polyimide supramolecular systems containing different amounts of azochromophore were tested as flexible supports that can be used in the fabrication of certain devices, such as sensors for monitoring the temperature changes, by coating them with conductive metals. That is why it is required to have good interfacial compatibility between the flexible substrate and the inorganic layer. The interface of the sensor elements must be designed in such a way as to improve the sensitivity, accuracy, and response time of the device. Laser irradiation is one of the commonly employed techniques used for surface adaptation by patterning polyimides to increase contact and enhance device reliability and signal transmission. In this context, this work highlights unreported aspects arising from the azo-polyimide morphology, local nanomechanical properties and wettability, which are impacting the compatibility with silver. The texture parameters indicate an improvement of the modulations' quality arising after laser irradiation through the phase mask, increasing the bearing capacity, fluid retention, and surface anisotropy when the amount of the azochromophore increases. The force curve spectroscopy and wettability studies indicated that the modification of the polymer morphology and surface chemistry lead to a better interfacial interaction with the metal lines when the azo component and the polyamidic acid are in equimolar quantities.
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Affiliation(s)
- Iuliana Stoica
- "Petru Poni" Institute of Macromolecular Chemistry, 700487 Iasi, Romania
| | | | - Cristian Ursu
- "Petru Poni" Institute of Macromolecular Chemistry, 700487 Iasi, Romania
| | - George Stoian
- National Institute of Research and Development for Technical Physics, 700050 Iasi, Romania
| | | | - Ion Sava
- "Petru Poni" Institute of Macromolecular Chemistry, 700487 Iasi, Romania
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The Impact of the Azo-Chromophore Sort on the Features of the Supramolecular Azopolyimide Films Desired to Be Used as Substrates for Flexible Electronics. Int J Mol Sci 2022; 23:ijms232315223. [PMID: 36499549 PMCID: PMC9738230 DOI: 10.3390/ijms232315223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
High-performance supramolecular polyimide systems were synthesized via a simple and innovative approach using two types of azo-chromophores, leading to concomitant special properties: high thermostability, the ability to be processed in the form of films with high flexibility, adequate morphological features, and good structuring capacity via phase mask ultraviolet (UV) laser irradiation, induced by the presence of the azo groups (-N=N-). The dimension and the anisotropy degree of the micro/nano patterns obtained on the surface of the flexible films (determined by atomic force microscopy) depend on the azo-dye type used in the supramolecular azopolyimide synthesis, which were higher when the azo-chromophore containing a -cyano group (-C≡N) was used. The molecular dynamics method, an excellent tool for an in-depth examination of the intermolecular interactions, was used to explain the morphological aspects. Energetic, dynamic and structural parameters were calculated for the two systems containing azo-chromophores, as well as for the pristine polymer system. It was highlighted that the van der Waals forces make a major contribution to the intermolecular interactions. The results from the combination of the dynamic analysis and the concentration profile explain the better mobility of the polyimide chains with a maximum content of azo groups in the cis configuration compared to the other systems. Taking all these data into account, the surfaces of the films can be tuned as required for the proposed applications, namely as substrates for flexible electronis.
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Progress on Polymers Containing Imide Rings for Advanced Technologies: A Contribution from ICMPP of the Romanian Academy. CHEMISTRY 2022. [DOI: 10.3390/chemistry4040088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Evolving technology has posed a constantly increasing need for materials that can work well under harsh conditions such as elevated temperatures. Aromatic polyimides have a great potential for this purpose, having excellent thermal, mechanical, dielectric, and optical properties, along with good chemical resistance and high dimensional stability. In spite of their general difficulty in processing and high cost, polyimides are intensively studied for applications in many areas due to their high-end value. This article reviews the progress made on polyimide materials in the “Petru Poni” Institute of Macromolecular Chemistry (ICMPP) of the Romanian Academy during the last decade, with focus on their performance as films, matrices for nanocomposites, coatings for microelectronics and opto-electronic devices, or dielectrics for thin film capacitors.
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Stoica I, Albu RM, Hulubei C, Astanei DG, Burlica R, Mersal GAM, Seaf Elnasr TA, Barzic AI, Elnaggar AY. A New Texturing Approach of a Polyimide Shielding Cover for Enhanced Light Propagation in Photovoltaic Devices. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3249. [PMID: 36145037 PMCID: PMC9505763 DOI: 10.3390/nano12183249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/09/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
The efficiency of photovoltaics (PVs) is related to cover material properties and light management in upper layers of the device. This article investigates new polyimide (PI) covers for PVs that enable light trapping through their induced surface texture. The latter is attained via a novel strategy that involves multi-directional rubbing followed by plasma exposure. Atomic force microscopy (AFM) is utilized to clarify the outcome of the proposed light-trapping approach. Since a deep clarification of either random or periodic surface morphology is responsible for the desired light capturing in solar cells, the elaborated texturing procedure generates a balance among both discussed aspects. Multidirectional surface abrasion with sand paper on pre-defined directions of the PI films reveals some relevant modifications regarding both surface morphology and the resulted degree of anisotropy. The illuminance experiments are performed to examine if the created surface texture is suitable for proper light propagation through the studied PI covers. The adhesion among the upper layers of the PV, namely the PI and transparent electrode, is evaluated. The correlation between the results of these analyses helps to identify not only adequate polymer shielding materials, but also to understand the chemical structure response to new design routes for light-trapping, which might significantly contribute to an enhanced conversion efficiency of the PV devices.
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Affiliation(s)
- Iuliana Stoica
- Department of Physical Chemistry of Polymers, “Petru Poni” Institute of Macromolecular Chemistry, 700487 Iasi, Romania
| | - Raluca Marinica Albu
- Department of Physical Chemistry of Polymers, “Petru Poni” Institute of Macromolecular Chemistry, 700487 Iasi, Romania
| | - Camelia Hulubei
- Department of Physical Chemistry of Polymers, “Petru Poni” Institute of Macromolecular Chemistry, 700487 Iasi, Romania
| | - Dragos George Astanei
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iasi, Romania
| | - Radu Burlica
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iasi, Romania
| | - Gaber A. M. Mersal
- Department of Chemistry, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
| | - Tarek A. Seaf Elnasr
- Department of Chemistry, College of Science, Jouf University, Sakaka P.O. Box 2014, Saudi Arabia
| | - Andreea Irina Barzic
- Department of Physical Chemistry of Polymers, “Petru Poni” Institute of Macromolecular Chemistry, 700487 Iasi, Romania
| | - Ashraf Y. Elnaggar
- Department of Food Science and Nutrition, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
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Wu D, Zhao X, Li X, Dong J, Zhang Q. Polyimide film containing sulfone groups with high dielectric properties. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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8
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McIntee OM, Welch BC, Greenberg AR, George SM, Bright VM. Elastic modulus of polyamide thin films formed by molecular layer deposition. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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9
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Dobryden I, Korolkov VV, Lemaur V, Waldrip M, Un HI, Simatos D, Spalek LJ, Jurchescu OD, Olivier Y, Claesson PM, Venkateshvaran D. Dynamic self-stabilization in the electronic and nanomechanical properties of an organic polymer semiconductor. Nat Commun 2022; 13:3076. [PMID: 35654891 PMCID: PMC9163058 DOI: 10.1038/s41467-022-30801-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/19/2022] [Indexed: 11/20/2022] Open
Abstract
The field of organic electronics has profited from the discovery of new conjugated semiconducting polymers that have molecular backbones which exhibit resilience to conformational fluctuations, accompanied by charge carrier mobilities that routinely cross the 1 cm2/Vs benchmark. One such polymer is indacenodithiophene-co-benzothiadiazole. Previously understood to be lacking in microstructural order, we show here direct evidence of nanosized domains of high order in its thin films. We also demonstrate that its device-based high-performance electrical and thermoelectric properties are not intrinsic but undergo rapid stabilization following a burst of ambient air exposure. The polymer's nanomechanical properties equilibrate on longer timescales owing to an orthogonal mechanism; the gradual sweating-out of residual low molecular weight solvent molecules from its surface. We snapshot the quasistatic temporal evolution of the electrical, thermoelectric and nanomechanical properties of this prototypical organic semiconductor and investigate the subtleties which play on competing timescales. Our study documents the untold and often overlooked story of a polymer device's dynamic evolution toward stability.
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Affiliation(s)
- Illia Dobryden
- Division of Surface and Corrosion Science, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Drottning Kristinas väg 51, SE-100 44, Stockholm, Sweden
- Experimental Physics, Division of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, SE-971 87, Luleå, Sweden
| | - Vladimir V Korolkov
- Park Systems UK Limited, MediCity Nottingham, Thane Road, NG90 6BH, Nottingham, UK.
| | - Vincent Lemaur
- Laboratory for Chemistry of Novel Materials, University of Mons, Place du Parc 20, B-7000, Mons, Belgium
| | - Matthew Waldrip
- Department of Physics and Center for Functional Materials, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Hio-Ieng Un
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Dimitrios Simatos
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Leszek J Spalek
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Oana D Jurchescu
- Department of Physics and Center for Functional Materials, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Yoann Olivier
- Laboratory for Computational Modelling of Functional Materials, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, B-5000, Namur, Belgium
| | - Per M Claesson
- Division of Surface and Corrosion Science, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Drottning Kristinas väg 51, SE-100 44, Stockholm, Sweden
| | - Deepak Venkateshvaran
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK.
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Sen AK, Chanda J, Shee B, Mazumder A, Dasgupta M, Ghosh P, Mukhopadhyay R. Improvement of thermo‐mechanical and fatigue crack growth resistance of tire sidewall compound by introducing syndiotactic polybutadiene. J Appl Polym Sci 2022. [DOI: 10.1002/app.52602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Amit Kumar Sen
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
| | - Jagannath Chanda
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
| | - Biswajit Shee
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
| | - Amrita Mazumder
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
| | - Mridul Dasgupta
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
| | - Prasenjit Ghosh
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
| | - Rabindra Mukhopadhyay
- Department of Advanced Material Research Group Hari Shankar Singhania Elastomer and Tyre Research Institute Mysore Karnataka India
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Sava I, Stoica I, Topala I, Mihaila I, Barzic AI. Photodesign and fabrication of surface relief gratings on films of polyimide-based supramolecular systems obtained using host-guest strategy. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Tuning the Physicochemical Properties of Nanostructured Materials through Advanced Preparation Methods. NANOMATERIALS 2022; 12:nano12060956. [PMID: 35335768 PMCID: PMC8954298 DOI: 10.3390/nano12060956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 02/05/2023]
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New Strategy for Inducing Surface Anisotropy in Polyimide Films for Nematics Orientation in Display Applications. NANOMATERIALS 2021; 11:nano11113107. [PMID: 34835871 PMCID: PMC8622647 DOI: 10.3390/nano11113107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 01/04/2023]
Abstract
The operability of liquid crystal displays is strongly impacted by the orientation aspects of nematics, which in turn are affected by the alignment layer surface features. In this work, two polyimide (PI) structures are obtained based on a cycloaliphatic dianhydride and aromatic or aliphatic diamines with distinct flexibility. The attained PI films have high transmittance (T) for visible radiations, i.e., at 550 nm T > 80%. Here, a novel strategy for creating surface anisotropy in the samples that combines rubbing with a cloth and stretching via pressing is reported. Birefringence and atomic force microscopy (AFM) scans reveal that the generated orientation of the chains is affected by the chemical structure of the polymer and order of the steps involved in the surface treatment. Molecular modeling computations and wettability tests show that the PI structure and produced surface topography are competitive factors, which are impacting the intensity of the interactions with the nematic liquid crystals. The achieved results are of great relevance for designing of reliable display devices with improved uniform orientation of liquid crystals.
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Olubowale O, Biswas S, Azom G, Prather BL, Owoso SD, Rinee KC, Marroquin K, Gates KA, Chambers MB, Xu A, Garno JC. "May the Force Be with You!" Force-Volume Mapping with Atomic Force Microscopy. ACS OMEGA 2021; 6:25860-25875. [PMID: 34660949 PMCID: PMC8515370 DOI: 10.1021/acsomega.1c03829] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 08/30/2021] [Indexed: 06/02/2023]
Abstract
Information of the chemical, mechanical, and electrical properties of materials can be obtained using force volume mapping (FVM), a measurement mode of scanning probe microscopy (SPM). Protocols have been developed with FVM for a broad range of materials, including polymers, organic films, inorganic materials, and biological samples. Multiple force measurements are acquired with the FVM mode within a defined 3D volume of the sample to map interactions (i.e., chemical, electrical, or physical) between the probe and the sample. Forces of adhesion, elasticity, stiffness, deformation, chemical binding interactions, viscoelasticity, and electrical properties have all been mapped at the nanoscale with FVM. Subsequently, force maps can be correlated with features of topographic images for identifying certain chemical groups presented at a sample interface. The SPM tip can be coated to investigate-specific reactions; for example, biological interactions can be probed when the tip is coated with biomolecules such as for recognition of ligand-receptor pairs or antigen-antibody interactions. This review highlights the versatility and diverse measurement protocols that have emerged for studies applying FVM for the analysis of material properties at the nanoscale.
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