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Belotcerkovtceva D, Nameirakpam H, Datt G, Noumbe U, Kamalakar MV. High current treated-passivated graphene (CTPG) towards stable nanoelectronic and spintronic circuits. NANOSCALE HORIZONS 2024; 9:456-464. [PMID: 38214968 DOI: 10.1039/d3nh00338h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Achieving enhanced and stable electrical quality of scalable graphene is crucial for practical graphene device applications. Accordingly, encapsulation has emerged as an approach for improving electrical transport in graphene. In this study, we demonstrate high-current treatment of graphene passivated by AlOx nanofilms as a new means to enhance the electrical quality of graphene for its scalable utilization. Our experiments and electrical measurements on large-scale chemical vapor-deposited (CVD) graphene devices reveal that high-current treatment causes persistent and irreversible de-trapping density in both bare graphene and graphene covered by AlOx. Strikingly, despite possible interfacial defects in graphene covered with AlOx, the high-current treatment enhances its carrier mobility by up to 200% in contrast to bare graphene samples, where mobility decreases. Spatially resolved Raman spectroscopy mapping confirms that surface passivation by AlOx, followed by the current treatment, reduces the number of sp3 defects in graphene. These results suggest that for current treated-passivated graphene (CTPG), the high-current treatment considerably reduces charged impurity and trapped charge densities, thereby reducing Coulomb scattering while mitigating any electromigration of carbon atoms. Our study unveils CTPG as an innovative system for practical utilization in graphene nanoelectronic and spintronic integrated circuits.
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Affiliation(s)
- Daria Belotcerkovtceva
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-751 20, Sweden.
| | - Henry Nameirakpam
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-751 20, Sweden.
| | - Gopal Datt
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-751 20, Sweden.
| | - Ulrich Noumbe
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-751 20, Sweden.
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504, 23 rue du Loess, Strasbourg 67034, France
| | - M Venkata Kamalakar
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-751 20, Sweden.
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2
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Brakat A, Zhu H. From Forces to Assemblies: van der Waals Forces-Driven Assemblies in Anisotropic Quasi-2D Graphene and Quasi-1D Nanocellulose Heterointerfaces towards Quasi-3D Nanoarchitecture. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2399. [PMID: 37686907 PMCID: PMC10489977 DOI: 10.3390/nano13172399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/14/2023] [Accepted: 08/19/2023] [Indexed: 09/10/2023]
Abstract
In the pursuit of advanced functional materials, the role of low-dimensional van der Waals (vdW) heterointerfaces has recently ignited noteworthy scientific interest, particularly in assemblies that incorporate quasi-2D graphene and quasi-1D nanocellulose derivatives. The growing interest predominantly stems from the potential to fabricate distinct genres of quasi-2D/1D nanoarchitecture governed by vdW forces. Despite the possibilities, the inherent properties of these nanoscale entities are limited by in-plane covalent bonding and the existence of dangling π-bonds, constraints that inhibit emergent behavior at heterointerfaces. An innovative response to these limitations proposes a mechanism that binds multilayered quasi-2D nanosheets with quasi-1D nanochains, capitalizing on out-of-plane non-covalent interactions. The approach facilitates the generation of dangling bond-free iso-surfaces and promotes the functionalization of multilayered materials with exceptional properties. However, a gap still persists in understanding transition and alignment mechanisms in disordered multilayered structures, despite the extensive exploration of monolayer and asymmetric bilayer arrangements. In this perspective, we comprehensively review the sophisticated aspects of multidimensional vdW heterointerfaces composed of quasi-2D/1D graphene and nanocellulose derivatives. Further, we discuss the profound impacts of anisotropy nature and geometric configurations, including in-plane and out-of-plane dynamics on multiscale vdW heterointerfaces. Ultimately, we shed light on the emerging prospects and challenges linked to constructing advanced functional materials in the burgeoning domain of quasi-3D nanoarchitecture.
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Affiliation(s)
| | - Hongwei Zhu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
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Asiri M, Srivastava N, Singh R, Al Ali A, Tripathi SC, Alqahtani A, Saeed M, Srivastava M, Rai AK, Gupta VK. Rice straw derived graphene-silica based nanocomposite and its application in improved co-fermentative microbial enzyme production and functional stability. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162765. [PMID: 36906037 DOI: 10.1016/j.scitotenv.2023.162765] [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: 12/28/2022] [Revised: 02/22/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
Cellulases are the one of the most highly demanded industrial biocatalysts due to their versatile applications, such as in the biorefinery industry. However, relatively poor efficiency and high production costs are included as the key industrial constraints that hinder enzyme production and utilization at economic scale. Furthermore, the production and functional efficiency of the β-glucosidase (BGL) enzyme is usually found to be relatively low among the cellulase cocktail produced. Thus, the current study focuses on fungi-mediated improvement of BGL enzyme in the presence of a rice straw-derived graphene-silica-based nanocomposite (GSNCs), which has been characterized using various techniques to analyze its physicochemical properties. Under optimized conditions of solid-state fermentation (SSF), co-fermentation using co-cultured cellulolytic enzyme has been done, and maximum enzyme production of 42 IU/gds FP, 142 IU/gds BGL, and 103 IU/gds EG have been achieved at a 5 mg concentration of GSNCs. Moreover, at a 2.5 mg concentration of nanocatalyst, the BGL enzyme showed its thermal stability at 60°C and 70 °C by holding its half-life relative activity for 7 h, while the same enzyme demonstrated pH stability at pH 8.0 and 9.0 for the 10 h. This thermoalkali BGL enzyme might be useful for the long-term bioconversion of cellulosic biomass into sugar.
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Affiliation(s)
- Mohammed Asiri
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
| | - Neha Srivastava
- Department of Chemical Engineering & Technology, Indian Institute of Technology (BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India.
| | - Rajeev Singh
- Department of Environmental Science, Jamia Millia Islamia (A Central University), New Delhi 110025, India
| | - Amer Al Ali
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, University of Bisha, Al Nakhil, Bisha, Saudi Arabia
| | - Subhash C Tripathi
- Institute of Applied Sciences & Humanities, Department of Chemistry, GLA University, Mathura 281406, Uttar Pradesh, India
| | - Abdulaziz Alqahtani
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
| | - Mohd Saeed
- Department of Biology, College of Sciences, University of Hail, Hail, Saudi Arabia
| | - Manish Srivastava
- Department of Chemical Engineering & Technology, Indian Institute of Technology (BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India; LCB Fertilizer Pvt. Ltd., Shyam Vihar Phase 2, Rani Sati Mandir Road, Lachchhipur, Gorakhpur, Uttar Pradesh 273015, India
| | - Ashutosh Kumar Rai
- Department of Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia
| | - Vijai Kumar Gupta
- Biorefining and Advanced Materials Research Center, SRUC, Kings Buildings, West Mains Road, Edinburgh EH9 3JG, UK; Center for Safe and Improved Food, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh EH9 3JG, UK.
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4
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Elshahawy MF, Ahmed NA, Mohammed RD, Ali AEH, Raafat AI. Radiation synthesis and photocatalytic performance of floated graphene oxide decorated ZnO/ alginate-based beads for methylene blue degradation under visible light irradiation. Int J Biol Macromol 2023:125121. [PMID: 37263325 DOI: 10.1016/j.ijbiomac.2023.125121] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 05/14/2023] [Accepted: 05/24/2023] [Indexed: 06/03/2023]
Abstract
Organic dye contamination, emanating from pharmaceutical, paper, and textile industries into water resources, severely threatens marine and human life even at low concentrations. Photocatalysis is one of the most important remediation techniques that decolorize water by employing the power of light. In this work, the development of floated beads of Sodium Alginate/hydroxyethyl methacrylate (Alg-g-HEMA) encompass graphene oxide (GO) decorated Zinc oxide (ZnO) utilizing ionizing radiation was designed to function as a photocatalyst when exposed to visible light. Floatability was induced using calcium carbonate. GO was sonochemically decorated with ZnO nanoparticles and the yield was characterized using XRD, FTIR, TEM, SEM, and EDX techniques. Optical characteristics of the developed nanostructure were performed using UV-Vis spectrophotometry. The photocatalytic activity of the floated (Alg-g-HEMA)-ZnO@GO beads was assessed for the photo decolorization of methylene blue dye (MB) under visible light. The upshot of operational factors such as photocatalyst dose, pH, initial dye concentration, and irradiation time on the decolorization of MB was examined. It was observed that 1 g of the developed (Alg-g-HEMA)-ZnO@GO photocatalyst was able to decolorize 1000 ml of 20 ppm of MB within 150 min at pH 9. In terms of kinetics, photo-decolorization follows Langmuir Hinshelwood pseudo-first order.
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Affiliation(s)
- Mai F Elshahawy
- Polymer Chemistry Department, National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt
| | - Nehad A Ahmed
- Polymer Chemistry Department, National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.
| | - Randa D Mohammed
- Polymer Chemistry Department, National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt
| | - Amr El-Hag Ali
- Polymer Chemistry Department, National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt
| | - Amany I Raafat
- Polymer Chemistry Department, National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt
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5
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Zare Y, Rhee KY, Park SJ. Progressing of a power model for electrical conductivity of graphene-based composites. Sci Rep 2023; 13:1596. [PMID: 36709238 PMCID: PMC9884220 DOI: 10.1038/s41598-023-28232-9] [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: 05/01/2022] [Accepted: 01/16/2023] [Indexed: 01/29/2023] Open
Abstract
This work presents a power equation for the conductivity of graphene-based polymer composites by the tunneling length, interphase deepness and filler size. The impressions of these factors on the effective concentration and percolation beginning of graphene nano-sheets in nanocomposites are also expressed. The developed equations for percolation beginning and conductivity are examined by the experimented data of some examples, which can guesstimate the interphase depth, tunneling size and percolation exponent. Besides, the impacts of numerous factors on the percolation beginning and conductivity are designed. The developed equation for percolation beginning shows the formation of thick interphase and large tunnels in the reported samples. So, disregarding of tunneling and interphase spaces in polymer graphene nanocomposites overpredicts the percolation beginning. Additionally, the developed model presents the acceptable calculations for the conductivity of samples. Among the mentioned parameters, the concentration and graphene conductivity in addition to the interphase depth induce the strongest effects on the conductivity of composites.
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Affiliation(s)
- Yasser Zare
- Biomaterials and Tissue Engineering Research Group, Department of Interdisciplinary Technologies, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran.
| | - Kyong Yop Rhee
- Department of Mechanical Engineering (BK21 Four), College of Engineering, Kyung Hee University, Yongin, Republic of Korea.
| | - Soo-Jin Park
- Department of Chemistry, Inha University, Incheon, 22212, Republic of Korea.
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6
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Zare Y, Rhee KY. An innovative model for conductivity of graphene-based system by networked nano-sheets, interphase and tunneling zone. Sci Rep 2022; 12:15179. [PMID: 36071132 PMCID: PMC9452680 DOI: 10.1038/s41598-022-19479-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 08/30/2022] [Indexed: 11/08/2022] Open
Abstract
This study presents a simple equation for the conductivity of graphene-filled nanocomposites by considering graphene size, amount of filler in the net, interphase deepness, tunneling size, and properties of the net. The amount of nanoparticles in the net is related to the percolation threshold and effective filler content. The novel model is analyzed using the measured conductivity of numerous examples and the factors' impacts on the conductivity. Both experienced data and parametric examinations verify the correctness of the novel model. Among the studied factors, filler amount and interphase deepness implicitly manage the conductivity from 0 to 7 S/m. It is explained that the interphase amount affects the operative quantity of nanofiller, percolation threshold, and amount of nets.
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Affiliation(s)
- Yasser Zare
- Biomaterials and Tissue Engineering Research Group, Department of Interdisciplinary Technologies, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran.
| | - Kyong Yop Rhee
- Department of Mechanical Engineering (BK21 Four), College of Engineering, Kyung Hee University, Yongin, Republic of Korea.
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7
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Lee HY, Haidari MM, Kee EH, Choi JS, Park BH, Campbell EEB, Jhang SH. Charge Transport in UV-Oxidized Graphene and Its Dependence on the Extent of Oxidation. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2845. [PMID: 36014709 PMCID: PMC9415921 DOI: 10.3390/nano12162845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/15/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Graphene oxides with different degrees of oxidation are prepared by controlling UV irradiation on graphene, and the charge transport and the evolution of the transport gap are investigated according to the extent of oxidation. With increasing oxygenous defect density nD, a transition from ballistic to diffusive conduction occurs at nD≃1012 cm-2 and the transport gap grows in proportion to nD. Considering the potential fluctuation related to the e-h puddle, the bandgap of graphene oxide is deduced to be Eg≃30nD(1012cm-2) meV. The temperature dependence of conductivity showed metal-insulator transitions at nD≃0.3×1012 cm-2, consistent with Ioffe-Regel criterion. For graphene oxides at nD≥4.9×1012 cm-2, analysis indicated charge transport occurred via 2D variable range hopping conduction between localized sp2 domain. Our work elucidates the transport mechanism at different extents of oxidation and supports the possibility of adjusting the bandgap with oxygen content.
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Affiliation(s)
- Hwa Yong Lee
- School of Physics, Konkuk University, Seoul 05029, Korea
| | | | - Eun Hee Kee
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Jin Sik Choi
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Bae Ho Park
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Eleanor E. B. Campbell
- EaStCHEM, School of Chemistry, Edinburgh University, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Sung Ho Jhang
- School of Physics, Konkuk University, Seoul 05029, Korea
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8
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Bantun F, Singh R, Alkhanani MF, Almalki AH, Alshammary F, Khan S, Haque S, Srivastava M. Gut microbiome interactions with graphene based nanomaterials: Challenges and opportunities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 830:154789. [PMID: 35341865 DOI: 10.1016/j.scitotenv.2022.154789] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/14/2022] [Accepted: 03/20/2022] [Indexed: 06/14/2023]
Abstract
Rapid growth of nanotechnology has accelerated immense possibility of engineered nanomaterials (ENMs) exposure by human and living organisms. In this context, wide range applications of graphene based nanomaterials (GBNMs) may inevitably cause their release into the environment. Consequently, potential risks to the ecological system and human health is consistently increasing due to the probable ingestion of GBNMs by mean of contaminated water or food sources. Further, gut microbiome is known to play a profound impact on the health status of human being and has been recognized as the most exciting advancement in the biomedical science. Recent studies has shown vital role of ENMs to alter gut microbiome and thereby changed pathological status of organisms. Therefore, in this review results of numerous studies dedicated to explore the impact of GBNMs on gut microbiome and thereby various pathological status have been summarized. Dietary exposure of different types of GBNMs [e.g. graphene, graphene oxide (GO), partially reduced graphene oxide (PRGO), graphene quantum dots (GQDs)] have been evaluated on the gut microbiome through numerous in vitro and in vivo models. Moreover, emphasis has been made to evaluate different physiological responses with the short/long-term exposure of GBNMs, particularly in gastrointestinal tract (GIT) and its correlation with gut microbiome and the health status. It is reviewed that exposure of GBNMs can exert significant impact which alter the composition, diversity and function of gut microbiome. This may further appear in terms of enteric disorder along with numerous pathological changes e.g. IEC (intestinal epithelial cells) colitis, lysosomal dysfunction, inflammation, shortened colon, resorbed embryo, retardation in skeletal development, low weight of fetus, early or late dead of fetus and IBD (inflammatory bowel disease) like symptoms. Finally, potential health risks due to the exposure of GBNMs have been discussed with future perspective.
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Affiliation(s)
- Farkad Bantun
- Department of Microbiology, Faculty of Medicine, Umm Al-Qura University, Makkah - 24382, Saudi Arabia
| | - Rajeev Singh
- Department of Environmental Studies, Satyawati College, University of Delhi, Delhi 110052, India.
| | - Mustfa F Alkhanani
- Emergency Medical Service Department, College of Applied Sciences, AlMaarefa University, Riyadh 11597, Saudi Arabia
| | - Atiah H Almalki
- Department of Pharmaceutical Chemistry, College of Pharmacy, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia; Addiction and Neuroscience Research Unit, College of Pharmacy, Taif University, Al-Hawiah, Taif 21944, Saudi Arabia
| | - Freah Alshammary
- Department of Preventive Dental Sciences, College of Dentistry, Hail University, Hail 2440, Saudi Arabia
| | - Saif Khan
- Department of Basic Dental and Medical Sciences, College of Dentistry, Hail University, Hail 2440, Saudi Arabia
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan 45142, Saudi Arabia; Bursa Uludağ University Faculty of Medicine, Görükle Campus, 16059 Nilüfer, Bursa, Turkey
| | - Manish Srivastava
- Department of Chemical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi 221005, India.
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9
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Zare Y, Rhee KY. Effect of contact resistance on the electrical conductivity of polymer graphene nanocomposites to optimize the biosensors detecting breast cancer cells. Sci Rep 2022; 12:5406. [PMID: 35354877 PMCID: PMC8967928 DOI: 10.1038/s41598-022-09398-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 03/14/2022] [Indexed: 11/08/2022] Open
Abstract
This study focuses on the contact regions among neighboring nanoparticles in polymer graphene nanocomposites by the extension of nanosheets. The resistance of graphene and the contact zones represent the total resistance of the prolonged nanosheets. Furthermore, the graphene size, interphase depth, and tunneling distance express the effective volume portion of graphene, while the onset of percolation affects the fraction of percolated nanosheets. Finally, a model is developed to investigate the conductivity of the samples using the graphene size, interphase depth, and tunneling size. In addition to the roles played by certain factors in conductivity, the experimental conductivity data for several samples confirm the conductivity predictions. Generally, the polymer sheet in tunnels determines the total resistance of the extended nanosheets because graphene ordinarily exhibits negligible resistance. In addition, a large tunnel positively accelerates the onset of percolation, but increases the tunneling resistance and attenuates the conductivity of the nanocomposite. Further, a thicker interphase and lower percolation threshold promote the conductivity of the system. The developed model can be applied to optimize the biosensors detecting the breast cancer cells.
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Affiliation(s)
- Yasser Zare
- Biomaterials and Tissue Engineering Research Group, Department of Interdisciplinary Technologies, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran.
| | - Kyong Yop Rhee
- Department of Mechanical Engineering (BK21 Four), College of Engineering, Kyung Hee University, Yongin, Republic of Korea.
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10
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Zare Y, Rhee KY. Advanced model for conductivity estimation of graphene-based samples considering interphase effect, tunneling mechanism, and filler wettability. J IND ENG CHEM 2021. [DOI: 10.1016/j.jiec.2021.12.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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11
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Lee JW, Jeong SP, You NH, Moon SY. Tunable Synthesis of Predominant Semi-Ionic and Covalent Fluorine Bonding States on a Graphene Surface. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:942. [PMID: 33917149 PMCID: PMC8067876 DOI: 10.3390/nano11040942] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/29/2021] [Accepted: 04/06/2021] [Indexed: 11/16/2022]
Abstract
In this study, fluorinated graphene (FG) was synthesized via a hydrothermal reaction. Graphene oxides (GOs) with different oxygen bonding states and oxygen contents (GO(F), GO(P), and GO(HU)) were used as starting materials. GO(F) and GO(P) are commercial-type GOs from Grapheneall. GO(HU) was prepared using a modified Hummers method. The synthesized FGs from GO(F), GO(P), and GO(HU) are denoted as FG(F), FG(P), and FG(HU), respectively. The F atoms were bound to the graphene surface with predominantly semi-ionic or covalent bonding depending on the GO oxygen state. FG(F) and FG(HU) exhibited less extensive fluorination than FG(P) despite the same or higher oxygen contents compared with that in FG(P). This difference was attributed to the difference in the C=O content of GOs because the C=O bonds in GO primarily produce covalent C-F bonds. Thus, FG(F) and FG(HU) mainly exhibited semi-ionic C-F bonds. The doped F atoms were used to tune the electronic properties and surface chemistry of graphene. The fluorination reaction also improved the extent of reduction of GO.
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Affiliation(s)
- Jae-Won Lee
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Chudong-ro 92, Bongdong-eup, Wanju-gun, Jeonbuk 55324, Korea; (J.-W.L.); (S.-P.J.); (N.-H.Y.)
- Department of Advanced Materials Science and Engineering, Hanyang University, Ansan 15588, Korea
| | - Seung-Pil Jeong
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Chudong-ro 92, Bongdong-eup, Wanju-gun, Jeonbuk 55324, Korea; (J.-W.L.); (S.-P.J.); (N.-H.Y.)
| | - Nam-Ho You
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Chudong-ro 92, Bongdong-eup, Wanju-gun, Jeonbuk 55324, Korea; (J.-W.L.); (S.-P.J.); (N.-H.Y.)
| | - Sook-Young Moon
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Chudong-ro 92, Bongdong-eup, Wanju-gun, Jeonbuk 55324, Korea; (J.-W.L.); (S.-P.J.); (N.-H.Y.)
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Gao D, Yang X, Teng P, Luo M, Zhang H, Liu Z, Yang J, Li Z, Wen X, Yuan L, Li K, Bowkett M, Copner N. In-fiber optofluidic online SERS detection of trace uremia toxin. OPTICS LETTERS 2021; 46:1101-1104. [PMID: 33649667 DOI: 10.1364/ol.418602] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 01/27/2021] [Indexed: 06/12/2023]
Abstract
In this Letter, we propose a microstructured in-fiber optofluidic surface-enhanced Raman spectroscopy (SERS) sensor for the initial inspection of uremia through the detection of unlabeled urea and creatinine. As a natural microfluidic device, microstructured hollow fiber has a special structure inside. Through chemical bonds, the SERS substrate can be modified and grown on the surface of the suspended core. Here, the silver nanoparticles (Ag NPs) are embedded on the poly diallyl dimethyl ammonium chloride-modified graphene oxide sheet to achieve the self-assembled SERS substrate. The reduced distance between Ag NPs can increase the strong hot spots that generate enhanced Raman signals. Therefore, it can effectively detect the Raman signal of unlabeled trace uremic toxin analytes (urea, creatinine) inside the optical fiber. The results show that under simulated biophysical conditions, the limit detection (LOD) for urea is 10-4M and the linearity is good, especially at the clinical conventional concentration range (2.5-6.5×10-3M). In addition, the online Raman detection of creatinine aqueous solution LOD is 10-6M, which also has good linearity. Significantly, this Letter provides a microstructured optofluidic in-fiber Raman sensor for the preliminary detection of uremia, which will have good development prospects in the field of clinical biomedicine.
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