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He M, Dong J, Zhang K, Ding F, Jiang H, Loiseau A, Lehtonen J, Kauppinen EI. Precise determination of the threshold diameter for a single-walled carbon nanotube to collapse. ACS NANO 2014; 8:9657-9663. [PMID: 25131158 DOI: 10.1021/nn5042812] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Closed-edged bilayer graphene nanoribbons were formed by the spontaneous collapse of large-diameter single-walled carbon nanotubes (SWNTs) grown on gold nanoparticles by chemical vapor deposition. Such bilayer graphene nanoribbons could adopt different stacking configurations, such as AB-stacking or stacking order with any rotation angle, correlated with the chiral angles of their parent rounded SWNTs. On the basis of the electron diffraction characterizations on a good number of collapsed and uncollapsed SWNTs, the threshold diameter for SWNTs to collapse was precisely determined to be 5.1 nm, independent of the chiral angle of the SWNTs. The determination is consistent with that calculated by both classical adaptive intermolecular reactive empirical bond order force field and density functional theory after having taken the stacking effect and thermal fluctuation into account.
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77
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Vlasova MA, Tarasova OS, Riikonen J, Raula J, Lobach AS, Borzykh AA, Smirin BV, Kauppinen EI, Eletskii AV, Herzig KH, Salonen J, Tavi P, Lehto VP, Järvinen K. Injected nanoparticles: The combination of experimental systems to assess cardiovascular adverse effects. Eur J Pharm Biopharm 2014; 87:64-72. [DOI: 10.1016/j.ejpb.2014.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 01/17/2014] [Accepted: 02/04/2014] [Indexed: 10/25/2022]
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78
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Anoshkin IV, Talyzin AV, Nasibulin AG, Krasheninnikov AV, Jiang H, Nieminen RM, Kauppinen EI. Coronene Encapsulation in Single-Walled Carbon Nanotubes: Stacked Columns, Peapods, and Nanoribbons. Chemphyschem 2014; 15:1660-5. [DOI: 10.1002/cphc.201301200] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Indexed: 11/09/2022]
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79
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Susi T, Kaukonen M, Havu P, Ljungberg MP, Ayala P, Kauppinen EI. Core level binding energies of functionalized and defective graphene. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:121-32. [PMID: 24605278 PMCID: PMC3943574 DOI: 10.3762/bjnano.5.12] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 01/17/2014] [Indexed: 05/09/2023]
Abstract
X-ray photoelectron spectroscopy (XPS) is a widely used tool for studying the chemical composition of materials and it is a standard technique in surface science and technology. XPS is particularly useful for characterizing nanostructures such as carbon nanomaterials due to their reduced dimensionality. In order to assign the measured binding energies to specific bonding environments, reference energy values need to be known. Experimental measurements of the core level signals of the elements present in novel materials such as graphene have often been compared to values measured for molecules, or calculated for finite clusters. Here we have calculated core level binding energies for variously functionalized or defected graphene by delta Kohn-Sham total energy differences in the real-space grid-based projector-augmented wave density functional theory code (GPAW). To accurately model extended systems, we applied periodic boundary conditions in large unit cells to avoid computational artifacts. In select cases, we compared the results to all-electron calculations using an ab initio molecular simulations (FHI-aims) code. We calculated the carbon and oxygen 1s core level binding energies for oxygen and hydrogen functionalities such as graphane-like hydrogenation, and epoxide, hydroxide and carboxylic functional groups. In all cases, we considered binding energy contributions arising from carbon atoms up to the third nearest neighbor from the functional group, and plotted C 1s line shapes by using experimentally realistic broadenings. Furthermore, we simulated the simplest atomic defects, namely single and double vacancies and the Stone-Thrower-Wales defect. Finally, we studied modifications of a reactive single vacancy with O and H functionalities, and compared the calculated values to data found in the literature.
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80
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He M, Jiang H, Lehtonen J, Kauppinen EI. Growth of single-walled carbon nanotubes with large chiral angles on rhodium nanoparticles. NANOSCALE 2013; 5:10200-10202. [PMID: 24056985 DOI: 10.1039/c3nr03259k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Single-walled carbon nanotubes (SWNTs) grown on rhodium (Rh) nanoparticles were demonstrated to have large chiral angles and a preference for metallic tubes.
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81
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Aitola K, Halme J, Feldt S, Lohse P, Borghei M, Kaskela A, Nasibulin AG, Kauppinen EI, Lund PD, Boschloo G, Hagfeldt A. Highly catalytic carbon nanotube counter electrode on plastic for dye solar cells utilizing cobalt-based redox mediator. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2013.07.202] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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82
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He M, Jiang H, Liu B, Fedotov PV, Chernov AI, Obraztsova ED, Cavalca F, Wagner JB, Hansen TW, Anoshkin IV, Obraztsova EA, Belkin AV, Sairanen E, Nasibulin AG, Lehtonen J, Kauppinen EI. Chiral-selective growth of single-walled carbon nanotubes on lattice-mismatched epitaxial cobalt nanoparticles. Sci Rep 2013; 3:1460. [PMID: 23492872 PMCID: PMC3597999 DOI: 10.1038/srep01460] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/25/2013] [Indexed: 02/05/2023] Open
Abstract
Controlling chirality in growth of single-walled carbon nanotubes (SWNTs) is important for exploiting their practical applications. For long it has been conceptually conceived that the structural control of SWNTs is potentially achievable by fabricating nanoparticle catalysts with proper structures on crystalline substrates via epitaxial growth techniques. Here, we have accomplished epitaxial formation of monometallic Co nanoparticles with well-defined crystal structure, and its use as a catalyst in the selective growth of SWNTs. Dynamics of Co nanoparticles formation and SWNT growth inside an atomic-resolution environmental transmission electron microscope at a low CO pressure was recorded. We achieved highly preferential growth of semiconducting SWNTs (~90%) with an exceptionally large population of (6, 5) tubes (53%) in an ambient CO atmosphere. Particularly, we also demonstrated high enrichment in (7, 6) and (9, 4) at a low growth temperature. These findings open new perspectives both for structural control of SWNTs and for elucidating the growth mechanisms.
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83
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Tison Y, Lin H, Lagoute J, Repain V, Chacon C, Girard Y, Rousset S, Henrard L, Zheng B, Susi T, Kauppinen EI, Ducastelle F, Loiseau A. Identification of nitrogen dopants in single-walled carbon nanotubes by scanning tunneling microscopy. ACS NANO 2013; 7:7219-7226. [PMID: 23829349 DOI: 10.1021/nn4026146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Using scanning tunnelling microscopy and spectroscopy, we investigated the atomic and electronic structure of nitrogen-doped single walled carbon nanotubes synthesized by chemical vapor deposition. The insertion of nitrogen in the carbon lattice induces several types of point defects involving different atomic configurations. Spectroscopic measurements on semiconducting nanotubes reveal that these local structures can induce either extended shallow levels or more localized deep levels. In a metallic tube, a single doping site associated with a donor state was observed in the gap at an energy close to that of the first van Hove singularity. Density functional theory calculations reveal that this feature corresponds to a substitutional nitrogen atom in the carbon network.
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84
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Chernov AI, Fedotov PV, Talyzin AV, Suarez Lopez I, Anoshkin IV, Nasibulin AG, Kauppinen EI, Obraztsova ED. Optical properties of graphene nanoribbons encapsulated in single-walled carbon nanotubes. ACS NANO 2013; 7:6346-6353. [PMID: 23795665 DOI: 10.1021/nn4024152] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report the photoluminescence (PL) from graphene nanoribbons (GNRs) encapsulated in single-walled carbon nanotubes (SWCNTs). New PL spectral features originating from GNRs have been detected in the visible spectral range. PL peaks from GNRs have resonant character, and their positions depend on the ribbon geometrical structure in accordance with the theoretical predictions. GNRs were synthesized using confined polymerization and fusion of coronene molecules. GNR@SWCNTs material demonstrates a bright photoluminescence both in infrared (IR) and visible regions. The photoluminescence excitation mapping in the near-IR spectral range has revealed the geometry-dependent shifts of the SWCNT peaks (up to 11 meV in excitation and emission) after the process of polymerization of coronene molecules inside the nanotubes. This behavior has been attributed to the strain of SWCNTs induced by insertion of the coronene molecules.
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85
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Wang M, Anoshkin IV, Nasibulin AG, Korhonen JT, Seitsonen J, Pere J, Kauppinen EI, Ras RHA, Ikkala O. Modifying native nanocellulose aerogels with carbon nanotubes for mechanoresponsive conductivity and pressure sensing. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:2428-32. [PMID: 23450504 DOI: 10.1002/adma.201300256] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Indexed: 05/04/2023]
Abstract
Mechanically excellent native cellulose nanofibers that are cleaved from plant cell walls have been modified by functionalized few-walled carbon nanotubes for hybrid nanofiber/nanotube aerogels. They show elastic mechanical behavior in combination with reversible electrical response under compression allowing responsive conductivity and pressure sensing. The concept combines wide availability of nanocellulosics and electrical functionality of carbon nanotubes synergistically.
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86
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Liu B, Jiang H, Krasheninnikov AV, Nasibulin AG, Ren W, Liu C, Kauppinen EI, Cheng HM. Chirality-dependent reactivity of individual single-walled carbon nanotubes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:1379-1386. [PMID: 23495250 DOI: 10.1002/smll.201202761] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 01/17/2013] [Indexed: 06/01/2023]
Abstract
Electronic characteristics of a single-walled carbon nanotube (SWCNT) strongly depend on minor variations in its atomic arrangement, specifically chirality. Therefore, precise control over nanotube chirality is highly desired for their application. Theoretically, SWCNTs with different structures have different chemical reactivities, which can be further used for their chirality selection. Here, an approach is developed to examine the relationship between the chirality of SWCNTs and their intrinsic chemical reactivity. By oxidizing individual, high-quality, suspended SWCNTs and using the nanobeam electron diffraction technique, it is shown that the reactivity of SWCNTs to O2 is intricately related to their diameters, metallicity, and chiral angles. In particular, even minor differences in chiral angles lead to big differences in their reactivity, which concords with first-principles calculations. Based on the experimental observations, a chirality-dependent reactivity sequence is constructed for SWCNTs. These findings shed light on effective chiral separation of SWCNTs for their practical application in many fields.
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87
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Raula J, Hanzlíková M, Rahikkala A, Hautala J, Kauppinen EI, Urtti A, Yliperttula M. Gas-phase synthesis of solid state DNA nanoparticles stabilized by l-leucine. Int J Pharm 2013; 444:155-61. [DOI: 10.1016/j.ijpharm.2013.01.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 01/11/2013] [Accepted: 01/13/2013] [Indexed: 10/27/2022]
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88
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Raula J, Rahikkala A, Halkola T, Pessi J, Peltonen L, Hirvonen J, Järvinen K, Laaksonen T, Kauppinen EI. Coated particle assemblies for the concomitant pulmonary administration of budesonide and salbutamol sulphate. Int J Pharm 2013. [DOI: 10.1016/j.ijpharm.2012.11.036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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89
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Tang DM, Zhang LL, Liu C, Yin LC, Hou PX, Jiang H, Zhu Z, Li F, Liu B, Kauppinen EI, Cheng HM. Heteroepitaxial growth of single-walled carbon nanotubes from boron nitride. Sci Rep 2012; 2:971. [PMID: 23240076 PMCID: PMC3521219 DOI: 10.1038/srep00971] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 11/26/2012] [Indexed: 11/09/2022] Open
Abstract
The growth of single-walled carbon nanotubes (SWCNTs) with predefined structure is of great importance for both fundamental research and their practical applications. Traditionally, SWCNTs are grown from a metal catalyst with a vapor-liquid-solid mechanism, where the catalyst is in liquid state with fluctuating structures, and it is intrinsically unfavorable for the structure control of SWCNTs. Here we report the heteroepitaxial growth of SWCNTs from a platelet boron nitride nanofiber (BNNF), which is composed of stacked (002) planes and is stable at high temperatures. SWCNTs are found to grow epitaxially from the open (002) edges of the BNNFs, and the diameters of the SWCNTs are multiples of the BN (002) interplanar distance. In situ transmission electron microscopy observations coupled with first principles calculations reveal that the growth of SWCNTs from the BNNFs follows a vapor-solid-solid mechanism. Our work opens opportunities for the control over the structure of SWCNTs by hetero-crystallographic epitaxy.
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90
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He M, Jiang H, Kauppinen EI, Lehtonen J. Diameter and chiral angle distribution dependencies on the carbon precursors in surface-grown single-walled carbon nanotubes. NANOSCALE 2012; 4:7394-7398. [PMID: 23085735 DOI: 10.1039/c2nr32276e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Carbon nanotubes grown from discrete Fe-containing nanoparticles dispersed on a silicon nitride transmission electron microscope grid were systematically studied. The (n,m) indices of produced single-walled carbon nanotubes (SWNTs) were deduced from their electron diffraction patterns. Relatively small diameter SWNTs with a narrow diameter distribution (0.7-1.6 nm) were produced using CO as the carbon source at 800 °C, while large diameter SWNTs ranging from 1.0 nm to 4.7 nm were synthesized when using CH(4) as the carbon source. The chiral angle distributions of the SWNTs produced from different carbon sources are also different, which are attributed to the preferred cap nucleation associated with the carbon feed rate on the catalyst instead of carbon nanotube growth kinetics. Furthermore, growth of carbon laminar nanoclusters inside carbon nanotubes was achieved at a higher growth temperature, suggesting that dissociated carbon diffuses across the nanoparticle during the nanotube growth process.
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91
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Soininen AJ, Rahikkala A, Korhonen JT, Kauppinen EI, Mezzenga R, Raula J, Ruokolainen J. Hierarchical Structures of Hydrogen-Bonded Liquid-Crystalline Side-Chain Diblock Copolymers in Nanoparticles. Macromolecules 2012. [DOI: 10.1021/ma301486p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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92
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Susi T, Kotakoski J, Arenal R, Kurasch S, Jiang H, Skakalova V, Stephan O, Krasheninnikov AV, Kauppinen EI, Kaiser U, Meyer JC. Atomistic description of electron beam damage in nitrogen-doped graphene and single-walled carbon nanotubes. ACS NANO 2012; 6:8837-46. [PMID: 23009666 DOI: 10.1021/nn303944f] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
By combining ab initio simulations with state-of-the-art electron microscopy and electron energy loss spectroscopy, we study the mechanism of electron beam damage in nitrogen-doped graphene and carbon nanotubes. Our results show that the incorporation of nitrogen atoms results in noticeable knock-on damage in these structures already at an acceleration voltage of 80 kV, at which essentially no damage is created in pristine structures at corresponding doses. Contrary to an early estimate predicting rapid destruction via sputtering of the nitrogen atoms, in the case of substitutional doping, damage is initiated by displacement of carbon atoms neighboring the nitrogen dopant, leading to the conversion of substitutional dopant sites into pyridinic ones. Although such events are relatively rare at 80 kV, they become significant at higher voltages typically used in electron energy loss spectroscopy studies. Correspondingly, we measured an energy loss spectrum time series at 100 kV that provides direct evidence for such conversions in nitrogen-doped single-walled carbon nanotubes, in excellent agreement with our theoretical prediction. Besides providing an improved understanding of the irradiation stability of these structures, we show that structural changes cannot be neglected in their characterization employing high-energy electrons.
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93
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Mustonen K, Susi T, Kaskela A, Laiho P, Tian Y, Nasibulin AG, Kauppinen EI. Influence of the diameter of single-walled carbon nanotube bundles on the optoelectronic performance of dry-deposited thin films. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2012; 3:692-702. [PMID: 23213633 PMCID: PMC3512119 DOI: 10.3762/bjnano.3.79] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 10/01/2012] [Indexed: 05/24/2023]
Abstract
The optoelectronic performance of thin films of single-walled carbon nanotubes (SWCNTs) was studied with respect to the properties of both individual nanotubes and their bundles. The SWCNTs were synthesized in a hot wire generator aerosol reactor, collected by gas filtration and dry-transferred onto various substrates. By thus completely avoiding liquid dispersion steps, we were able to avoid any artifacts from residual surfactants or sonication. We found that bundle lengths determined the thin-film performance, as would be expected for highly resistive bundle-bundle junctions. However, we found no evidence that contact resistances were affected by the bundle diameters, although they did play a secondary role by simply affecting the absorption. The individual SWCNT diameters and their graphitization level as gauged by the Raman D band intensity did not show any clear correlation with the overall performance.
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94
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Sairanen E, Karinen R, Borghei M, Kauppinen EI, Lehtonen J. Preparation Methods for Multi-Walled Carbon Nanotube Supported Palladium Catalysts. ChemCatChem 2012. [DOI: 10.1002/cctc.201200344] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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95
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Aitola K, Borghei M, Kaskela A, Kemppainen E, Nasibulin AG, Kauppinen EI, Lund PD, Ruiz V, Halme J. Flexible metal-free counter electrode for dye solar cells based on conductive polymer and carbon nanotubes. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2012.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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96
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Raula J, Seppälä J, Malm J, Karppinen M, Kauppinen EI. Structure and dissolution of L-leucine-coated salbutamol sulphate aerosol particles. AAPS PharmSciTech 2012; 13:707-12. [PMID: 22562614 DOI: 10.1208/s12249-012-9789-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 04/04/2012] [Indexed: 11/30/2022] Open
Abstract
L-Leucine formed different crystalline coatings on salbutamol sulphate aerosol particles depending on the saturation conditions of L-leucine. The work emphasizes a careful characterization of powders where structural compartments such as crystal size and particle coating may affect the performance of drug when administered. The sublimation of L-leucine from the aerosol particles took place 90°C lower temperature than the bulk L-leucine which was attributed to result from the sublimation of L-leucine from nano-sized crystalline domains. The dissolution slowed down and initial dissolution rate decreased with increasing L-leucine content. Decreasing crystalline domains to nano-scale improve heat and mass transfer which was observed as the lowered decomposition temperature of the drug salbutamol sulphate and the sublimation temperature of surface material L-leucine as well as the altered dissolution characteristics of the drug. The structure of the coated drug particles was studied by means of thermal analysis techniques (DSC and TG), and the dissolution of salbutamol sulphate was studied as an on-line measurement in a diffusion cell.
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97
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Talyzin AV, Luzan SM, Anoshkin IV, Nasibulin AG, Jiang H, Kauppinen EI. Hydrogen-Driven Collapse of C 60Inside Single-Walled Carbon Nanotubes. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201200946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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98
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Rackauskas S, Mustonen K, Järvinen T, Mattila M, Klimova O, Jiang H, Tolochko O, Lipsanen H, Kauppinen EI, Nasibulin AG. Synthesis of ZnO tetrapods for flexible and transparent UV sensors. NANOTECHNOLOGY 2012; 23:095502. [PMID: 22327417 DOI: 10.1088/0957-4484/23/9/095502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
ZnO tetrapods (ZnO-Ts) were synthesized in a vertical flow reactor by gas phase oxidation of Zn vapor in an air atmosphere. The morphology of the product was varied from nearly spherical nanoparticles to ZnO-Ts, together with the partial pressure of Zn and reaction temperature. MgO introduced during synthesis, increased the band gap, the optical transparency in the visible range, and also changed the ZnO-T structure. Fabricated flexible transparent UV sensors showed a 45-fold current increase under UV irradiation with an intensity of 30 μW cm(-2) at a wavelength of 365 nm and response time of 0.9 s.
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99
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Mikheev GM, Nasibulin AG, Zonov RG, Kaskela A, Kauppinen EI. Photon-drag effect in single-walled carbon nanotube films. NANO LETTERS 2012; 12:77-83. [PMID: 22112234 DOI: 10.1021/nl203003p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We observed an interaction of single-walled carbon nanotube films with obliquely incident nanosecond laser radiation in visible and infrared regions generating unipolar voltage pulses replicating the shape of the laser pulses. The photoelectric signal significantly depends on the laser polarization and has maximum value at the laser beam incidence angle of ±65° and at the film thickness of 350 nm. The results are explained in the framework of the photon-drag effect.
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100
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Bimbo LM, Mäkilä E, Raula J, Laaksonen T, Laaksonen P, Strommer K, Kauppinen EI, Salonen J, Linder MB, Hirvonen J, Santos HA. Functional hydrophobin-coating of thermally hydrocarbonized porous silicon microparticles. Biomaterials 2011; 32:9089-99. [DOI: 10.1016/j.biomaterials.2011.08.011] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 08/05/2011] [Indexed: 11/17/2022]
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