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Jia Y, Liu D, Chen D, Jin Y, Chen C, Tao J, Cheng H, Zhou S, Cheng B, Wang X, Meng Z, Liu T. Transparent dynamic infrared emissivity regulators. Nat Commun 2023; 14:5087. [PMID: 37607928 PMCID: PMC10444874 DOI: 10.1038/s41467-023-40902-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 08/14/2023] [Indexed: 08/24/2023] Open
Abstract
Dynamic infrared emissivity regulators, which can efficiently modulate infrared radiation beyond vision, have emerged as an attractive technology in the energy and information fields. The realization of the independent modulation of visible and infrared spectra is a challenging and important task for the application of dynamic infrared emissivity regulators in the fields of smart thermal management and multispectral camouflage. Here, we demonstrate an electrically controlled infrared emissivity regulator that can achieve independent modulation of the infrared emissivity while maintaining a high visible transparency (84.7% at 400-760 nm). The regulators show high degree of emissivity regulation (0.51 at 3-5 μm, 0.41 at 7.5-13 μm), fast response ( < 600 ms), and long cycle life ( > 104 cycles). The infrared emissivity regulation is attributed to the modification of the carrier concentration in the surface depletion layer of aluminum-doped zinc oxide nanocrystals. This transparent infrared emissivity regulator provides opportunities for applications such as on-demand smart thermal management, multispectral displays, and adaptive camouflage.
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Affiliation(s)
- Yan Jia
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
| | - Dongqing Liu
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China.
| | - Desui Chen
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, P.R. China
| | - Yizheng Jin
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, P.R. China
| | - Chen Chen
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
| | - Jundong Tao
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
| | - Haifeng Cheng
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China.
| | - Shen Zhou
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
- Institute for Quantum Science and Technology, College of Science, National University of Defense Technology, Changsha, P.R. China
| | - Baizhang Cheng
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
| | - Xinfei Wang
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
| | - Zhen Meng
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
| | - Tianwen Liu
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, P.R. China
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Noroozi S, Safa F, Shariati S, Islamnezhad A. Differential pulse voltammetric assessment of phthalate molecular blocking effect on the copper electrode modified by multi-walled carbon nanotubes: Statistical optimization by Box-Behnken experimental design. ARAB J CHEM 2023. [DOI: 10.1016/j.arabjc.2023.104874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
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Shkirskiy V, Levillain E, Gautier C. Capacitive Impedance for Following In-Situ Grafting Kinetics of Diazonium Salts. Chemphyschem 2021; 22:1074-1078. [PMID: 33780116 DOI: 10.1002/cphc.202100154] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/26/2021] [Indexed: 11/06/2022]
Abstract
A new method to follow in-situ grafting kinetics of diazonium compounds based on imposing small amplitude high frequency AC oscillations at grafting potential, is outlined. This enables the time-resolved measurements of capacitive impedance concomitantly with the growth of the organic layer at the working electrode. The impedance values were quantitatively correlated with the ex-situ (from voltammograms) and in-situ (from quartz crystal microbalance) measured surface coverages, providing a validation of the new methodology. The versatility of the developed approach was demonstrated on the grafting via reduction of 4-nitrobenzenediazonium on Au and glassy carbon (GC) substrates and via deposition of in-situ generated diazonium salts from 1-aminoanthraquinone and 4-ferrocenylaniline on GC. The capacitive impedance measurements are simple, fast, and non-destructive, making it an appealing methodology for an exploration of grafting kinetics of a wide range of diazonium salts.
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Affiliation(s)
- Viacheslav Shkirskiy
- MOLTECH-Anjou, Université D'Angers, UMR CNRS 6200, 2 Boulevard Lavoisier, 49045, Angers, France
| | - Eric Levillain
- MOLTECH-Anjou, Université D'Angers, UMR CNRS 6200, 2 Boulevard Lavoisier, 49045, Angers, France
| | - Christelle Gautier
- MOLTECH-Anjou, Université D'Angers, UMR CNRS 6200, 2 Boulevard Lavoisier, 49045, Angers, France
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Tuning the Covering on Gold Surfaces by Grafting Amino-Aryl Films Functionalized with Fe(II) Phthalocyanine: Performance on the Electrocatalysis of Oxygen Reduction. Molecules 2021; 26:molecules26061631. [PMID: 33804112 PMCID: PMC7998582 DOI: 10.3390/molecules26061631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 11/29/2022] Open
Abstract
Current selective modification methods, coupled with functionalization through organic or inorganic molecules, are crucial for designing and constructing custom-made molecular materials that act as electroactive interfaces. A versatile method for derivatizing surfaces is through an aryl diazonium salt reduction reaction (DSRR). A prominent feature of this strategy is that it can be carried out on various materials. Using the DSRR, we modified gold surface electrodes with 4-aminebenzene from 4-nitrobenzenediazonium tetrafluoroborate (NBTF), regulating the deposited mass of the aryl film to achieve covering control on the electrode surface. We got different degrees of covering: monolayer, intermediate, and multilayer. Afterwards, the ArNO2 end groups were electrochemically reduced to ArNH2 and functionalized with Fe(II)-Phthalocyanine to study the catalytic performance for the oxygen reduction reaction (ORR). The thickness of the electrode covering determines its response in front of ORR. Interestingly, the experimental results showed that an intermediate covering film presents a better electrocatalytic response for ORR, driving the reaction by a four-electron pathway.
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Phal S, Shimizu K, Mwanza D, Mashazi P, Shchukarev A, Tesfalidet S. Electrografting of 4-Carboxybenzenediazonium on Glassy Carbon Electrode: The Effect of Concentration on the Formation of Mono and Multilayers. Molecules 2020; 25:E4575. [PMID: 33036378 PMCID: PMC7582525 DOI: 10.3390/molecules25194575] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/26/2020] [Accepted: 10/03/2020] [Indexed: 11/25/2022] Open
Abstract
Grafting of electrodes with diazonium salts using cyclic voltammetry (CV) is a well-established procedure for surface modification. However, little is known about the effect of the concentration of the diazonium salt on the number of layers grafted on the electrode surface. In this work, the impact of concentration on the grafting of 4-carboxybenzenediazonium (4-CBD) onto a glassy carbon electrode (GCE) is elucidated. The number of layers grafted on the GCE was linearly dependent on the concentration of 4-CBD and varied between 0.9 and 4.3 when the concentration was varied between 0.050 and 0.30 mmol/L at 0.10 V.s-1. Characterization of modified glassy carbon surface with X-ray photoelectron spectroscopy (XPS) confirmed the grafting of carboxyphenyl layer on the surface. Grafting with 0.15 mmol/L 4-CBD (1 CV cycle) did not form a detectable amount of carboxyphenyl (CP) moieties at the surface, while a single scan with higher concentration (2.5 mmol/L) or multiple scans (22 cycles) gave detectable signals, indicating formation of multilayers. We also demonstrate the possibility of removing the thin layer grafted on a glassy carbon electrode by applying high oxidation potential +1.40 V.
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Affiliation(s)
- Sereilakhena Phal
- Department of Chemistry, Umeå University, SE 90187 Umeå, Sweden; (S.P.); (K.S.); (A.S.)
| | - Kenichi Shimizu
- Department of Chemistry, Umeå University, SE 90187 Umeå, Sweden; (S.P.); (K.S.); (A.S.)
| | - Daniel Mwanza
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa; (D.M.); (P.M.)
| | - Philani Mashazi
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa; (D.M.); (P.M.)
- Institute for Nanotechnology Innovation Centre, Rhodes University, Grahamstown 6140, South Africa
| | - Andrey Shchukarev
- Department of Chemistry, Umeå University, SE 90187 Umeå, Sweden; (S.P.); (K.S.); (A.S.)
| | - Solomon Tesfalidet
- Department of Chemistry, Umeå University, SE 90187 Umeå, Sweden; (S.P.); (K.S.); (A.S.)
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Yates ND, Dowsett MR, Bentley P, Dickenson-Fogg JA, Pratt A, Blanford CF, Fascione MA, Parkin A. Aldehyde-Mediated Protein-to-Surface Tethering via Controlled Diazonium Electrode Functionalization Using Protected Hydroxylamines. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:5654-5664. [PMID: 31721585 DOI: 10.1021/acs.langmuir.9b01254] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report a diazonium electro-grafting method for the covalent modification of conducting surfaces with aldehyde-reactive hydroxylamine functionalities that facilitate the wiring of redox-active (bio)molecules to electrode surfaces. Hydroxylamine near-monolayer formation is achieved via a phthalimide-protection and hydrazine-deprotection strategy that overcomes the multilayer formation that typically complicates diazonium surface modification. This surface modification strategy is characterized using electrochemistry (electrochemical impedance spectroscopy and cyclic voltammetry), X-ray photoelectron spectroscopy, and quartz crystal microbalance with dissipation monitoring. Thus-modified glassy carbon, boron-doped diamond, and gold surfaces are all shown to ligate to small molecule aldehydes, yielding surface coverages of 150-170, 40, and 100 pmol cm-2, respectively. Bioconjugation is demonstrated via the coupling of a dilute (50 μM) solution of periodate-oxidized horseradish peroxidase enzyme to a functionalized gold surface under biocompatible conditions (H2O solvent, pH 4.5, 25 °C).
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Affiliation(s)
- Nicholas D Yates
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Mark R Dowsett
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Phillip Bentley
- Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Jack A Dickenson-Fogg
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Andrew Pratt
- Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Christopher F Blanford
- School of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Martin A Fascione
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Alison Parkin
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom
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7
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Electrochemical and photoelectrochemical properties of a hybrid film made of Ru(II) complex and Zn(II)-substituted tungstoborate. J Solid State Electrochem 2018. [DOI: 10.1007/s10008-018-4121-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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8
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Mooste M, Kibena-Põldsepp E, Marandi M, Matisen L, Sammelselg V, Podvorica FI, Tammeveski K. Surface and electrochemical characterization of aryl films grafted on polycrystalline copper from the diazonium compounds using the rotating disk electrode method. J Electroanal Chem (Lausanne) 2018. [DOI: 10.1016/j.jelechem.2018.03.070] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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Brooksby PA, Shields JD, Farquhar AK, Downard AJ. Reduction of Nitrophenyl Films in Aqueous Solutions: How Many Electrons? ChemElectroChem 2016. [DOI: 10.1002/celc.201600395] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Paula A. Brooksby
- MacDiarmid Institute for Advanced Materials and Nanotechnology; Department of Chemistry; University of Canterbury; Christchurch 8140 New Zealand
| | - James D. Shields
- MacDiarmid Institute for Advanced Materials and Nanotechnology; Department of Chemistry; University of Canterbury; Christchurch 8140 New Zealand
| | - Anna K. Farquhar
- MacDiarmid Institute for Advanced Materials and Nanotechnology; Department of Chemistry; University of Canterbury; Christchurch 8140 New Zealand
| | - Alison J. Downard
- MacDiarmid Institute for Advanced Materials and Nanotechnology; Department of Chemistry; University of Canterbury; Christchurch 8140 New Zealand
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10
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Mooste M, Kibena-Põldsepp E, Marandi M, Matisen L, Sammelselg V, Tammeveski K. Electrochemical properties of gold and glassy carbon electrodes electrografted with an anthraquinone diazonium compound using the rotating disc electrode method. RSC Adv 2016. [DOI: 10.1039/c6ra05609a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The RDE method was combined with the electrografting procedure to prepare thick AQ films on Au and glassy carbon electrodes.
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Affiliation(s)
- M. Mooste
- Institute of Chemistry
- University of Tartu
- 50411 Tartu
- Estonia
| | | | - M. Marandi
- Institute of Physics
- University of Tartu
- 50411 Tartu
- Estonia
| | - L. Matisen
- Institute of Physics
- University of Tartu
- 50411 Tartu
- Estonia
| | - V. Sammelselg
- Institute of Chemistry
- University of Tartu
- 50411 Tartu
- Estonia
- Institute of Physics
| | - K. Tammeveski
- Institute of Chemistry
- University of Tartu
- 50411 Tartu
- Estonia
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11
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Gold-organic thin films from the reductive grafting of diazonium gold(III) salts. J Electroanal Chem (Lausanne) 2015. [DOI: 10.1016/j.jelechem.2015.09.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Chevalier CL, Landis EC. Electrochemical Attachment of Diazonium-Generated Films on Nanoporous Gold. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:8633-8641. [PMID: 26186600 DOI: 10.1021/acs.langmuir.5b02302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Nanoporous gold provides a high surface area platform for further chemistry, but the stability of the molecular linkages to the surface will limit applications. We attached aryl molecular layers to nanoporous gold electrodes through electrochemical reduction of the corresponding aryl-diazonium salt and studied the properties and stability of the resulting films in varied attachment conditions. Infrared reflection absorption spectroscopy and X-ray photoelectron spectroscopy were used to confirm the presence of the molecular layers. X-ray photoelectron spectroscopy indicates that the molecular layer is thick and that attachment conditions can form multilayers. However, cyclic voltammetry shows that the multilayers do not block electrochemical activity at the nanoporous gold surface. The molecular layers are resistant to replacement by alkane-thiol chains and exhibit some stability with respect to applied potential. These results indicate that a thick but highly defective molecular film forms with a mixture of strongly and weakly bound molecules.
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Affiliation(s)
- Christine L Chevalier
- Department of Chemistry, College of the Holy Cross, 1 College Street Box C, Worcester, Massachusetts 01610, United States
| | - Elizabeth C Landis
- Department of Chemistry, College of the Holy Cross, 1 College Street Box C, Worcester, Massachusetts 01610, United States
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Menanteau T, Levillain E, Downard AJ, Breton T. Evidence of monolayer formation via diazonium grafting with a radical scavenger: electrochemical, AFM and XPS monitoring. Phys Chem Chem Phys 2015; 17:13137-42. [DOI: 10.1039/c5cp01401h] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
AFM monitoring of controlled surface modification with a radical scavenger.
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Affiliation(s)
- T. Menanteau
- MOLTECH-Anjou
- Université d'Angers
- UMR CNRS 6200
- 49045 Angers
- France
| | - E. Levillain
- MOLTECH-Anjou
- Université d'Angers
- UMR CNRS 6200
- 49045 Angers
- France
| | - A. J. Downard
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Department of Chemistry
- University of Canterbury
- Christchurch 8140
- New Zealand
| | - T. Breton
- MOLTECH-Anjou
- Université d'Angers
- UMR CNRS 6200
- 49045 Angers
- France
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Verberne-Sutton SD, Quarels RD, Zhai X, Garno JC, Ragains JR. Application of Visible Light Photocatalysis with Particle Lithography To Generate Polynitrophenylene Nanostructures. J Am Chem Soc 2014; 136:14438-44. [DOI: 10.1021/ja505521k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Susan D. Verberne-Sutton
- Department of Chemistry, Louisiana State University, 232
Choppin Hall, Baton
Rouge, Louisiana 70803, United States
| | - Rashanique D. Quarels
- Department of Chemistry, Louisiana State University, 232
Choppin Hall, Baton
Rouge, Louisiana 70803, United States
| | - Xianglin Zhai
- Department of Chemistry, Louisiana State University, 232
Choppin Hall, Baton
Rouge, Louisiana 70803, United States
| | - Jayne C. Garno
- Department of Chemistry, Louisiana State University, 232
Choppin Hall, Baton
Rouge, Louisiana 70803, United States
| | - Justin R. Ragains
- Department of Chemistry, Louisiana State University, 232
Choppin Hall, Baton
Rouge, Louisiana 70803, United States
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Vacca A, Mascia M, Rizzardini S, Palmas S, Mais L. Coating of gold substrates with polyaniline through electrografting of aryl diazonium salts. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2013.08.187] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Electrocatalysis of oxygen reduction on glassy carbon electrodes modified with anthraquinone moieties. J Solid State Electrochem 2014. [DOI: 10.1007/s10008-014-2392-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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17
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An Immunosensor for Pathogenic Staphylococcus aureus Based on Antibody Modified Aminophenyl-Au Electrode. ACTA ACUST UNITED AC 2013. [DOI: 10.1155/2013/367872] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The objective of this work is to elaborate an immunosensing system which will detect and quantify Staphylococcus aureus bacteria. A gold electrode was modified by electrografting of 4-nitrophenyl diazonium, in situ synthesized in acidic aqueous solution. The immunosensor was fabricated by immobilizing affinity-purified polyclonal anti S. aureus antibodies on the modified gold electrode. Cyclic voltammetry (CV) and Faradaic Electrochemical Impedance Spectroscopy (EIS) were employed to characterize the stepwise assembly of the immunosensor. The performance of the developed immunosensor was evaluated by monitoring the electron-transfer resistance detected using Faradaic EIS. The experimental results indicated a linear relationship between the relative variation of the electron transfer resistance and the logarithmic value of S. aureus concentration, with a slope of 0.40 ± 0.08 per decade of concentration. A low quantification limit of 10±2 CFU per ml and a linear range up to 107±2×106 CFU per mL were obtained. The developed immunosensors showed high selectivity to Escherichia coli and Staphylococcus saprophyticus.
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Kibena E, Marandi M, Mäeorg U, Venarusso LB, Maia G, Matisen L, Kasikov A, Sammelselg V, Tammeveski K. Electrochemical modification of gold electrodes with azobenzene derivatives by diazonium reduction. Chemphyschem 2013; 14:1043-54. [PMID: 23420610 DOI: 10.1002/cphc.201200934] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Indexed: 11/10/2022]
Abstract
An electrochemical study of Au electrodes electrografted with azobenzene (AB), Fast Garnet GBC (GBC) and Fast Black K (FBK) diazonium compounds is presented. Electrochemical quartz crystal microbalance, ellipsometry and atomic force microscopy investigations reveal the formation of multilayer films. The elemental composition of the aryl layers is examined by X-ray photoelectron spectroscopy. The electrochemical measurements reveal a quasi-reversible voltammogram of the Fe(CN)6 (3-/4-) redox couple on bare Au and a sigmoidal shape for the GBC- and FBK-modified Au electrodes, thus demonstrating that electron transfer is blocked due to the surface modification. The electrografted AB layer results in strongest inhibition of the Fe(CN)6 (3-/4-) response compared with other aryl layers. The same tendencies are observed for oxygen reduction; however, the blocking effect is not as strong as in the Fe(CN)6 (3-/4-) redox system. The electrochemical impedance spectroscopy measurements allowed the calculation of low charge-transfer rates to the Fe(CN)6 (3-) probe for the GBC- and FBK-modified Au electrodes in relation to bare Au. From these measurements it can be concluded that the FBK film is less compact or presents more pinholes than the electrografted GBC layer.
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Affiliation(s)
- Elo Kibena
- Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
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OH radical degradation of blocking aryl layers on glassy carbon and gold electrodes leads to film thinning on glassy carbon and pinhole films on gold. Electrochem commun 2013. [DOI: 10.1016/j.elecom.2013.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Nanostructured electrocatalysts immobilised on electrode surfaces and organic film templates. CHEMICAL PAPERS 2012. [DOI: 10.2478/s11696-011-0110-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AbstractThe development of new electrocatalysts with the aim of enhancing the rate of electrochemical reactions has been a long-term goal of electrochemists. In part, this is due to the great importance of electrocatalysts in energy generation and environmental concerns. In this review, various methods of the preparation of nanostructured electrocatalysts and their applications after attachment to the electrode surface are described. Diazonium chemistry has been extensively used for the preparation and attachment of nanostructured electrocatalysts and this review thus describes the recent developments and applications of this chemistry in electrocatalysis. The preparation of nanostructured electrocatalysts including grafted molecular films and metal nanoparticles physically adsorbed on electrode surfaces and those attached to the surface by molecular links using diazonium chemistry is reviewed. Two methods for the attachment of nanoparticles by simple physical adsorption and by electrochemical deposition on molecular films are described and the electrochemical response of nanostructured electrocatalysts for some of the most common electrochemical reactions is discussed.
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21
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Versatile charge transfer through anthraquinone films for electrochemical sensing applications. Electrochim Acta 2011. [DOI: 10.1016/j.electacta.2011.07.126] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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