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1
Content available Ziemia ubijana stabilizowana cementem jako materiał konstrukcyjny – ocena nasiąkliwości
Narloch A., Woyciechowski P., Rosicki Ł., Cichocki D.
Przegląd Budowlany
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2015
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R. 86, nr 5
22--25
PL
W dotychczasowych badaniach autorów dowiedziono, że ziemia ubijana niestabilizowana ze względów wytrzymałościowych może z powodzeniem zostać zastosowana jako materiał do wznoszenia nośnych monolitycznych przegród pionowych. O konieczności zastosowania dodatku stabilizującego do mieszanki ziemi w klimacie umiarkowanym będzie decydować natomiast odporność ziemi na czynniki atmosferyczne. Badania rozpoznawcze wykazały, że próbki ziemi ubijanej niestabilizowanej łatwo rozmiękają w wodzie. W niniejszym artykule przeanalizowano nasiąkliwość ziemi ubijanej stabilizowanej różną ilością cementu CEM I 42,5 R.
EN
The research carried out so far proves that the compacted ground, which is not stabilized for strength reasons, may be successfully used as a material for erection of monolithic vertical bulkheads. When it comes to the need of using a stabilizing additive in the ground mixture in the temperate climate, weather resistance of the ground would be the deciding factor. The initial research shows that the ground samples regarding the compacted, non-stabilized ground are easily softened by water. The present article analyzes the absorptivity of the compacted ground, stabilized with a variety of quantity of CEM I 42.5R cement.
2
Content available remote Manufacturing and structure of nanocomposites consisting of MWCNTs decorated respectively with Rh, Re and Pt nanocristals
Dobrzańska-Danikiewicz A. D., Łukowiec D., Wolany W., Cichocki D.
Journal of Achievements in Materials and Manufacturing Engineering
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2015
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Vol. 72, nr 1
39--44
EN
Purpose: The primary aim of the paper is to compare fabrication methods and present newly fabricated nanocomposites whose structural components are multi-walled carbon nanotubes (MWCNTs) and respectively Rh, Re and Pt nanocrystals. Design/methodology/approach: The newly fabricated nanocomposites underwent Transmission Electron Microscopy (TEM) examinations in the bright to show their structure. Spectroscopy examinations were carried out, as well, to determine chemical composition of the material. Findings: It was found based on a comparative analysis of the structure of selected nanocomposites that functionalisation methods and a reduction method of precursors of selected noble elements have a significant effect on the structure and morphology of the compared carbon nanocomposites. Research limitations/implications: Nanocomposites consisting of carbon nanotubes decorated with metal nanoparticles possess special electrical properties and a developed specific area, which makes them particularly suitable as active elements of industrial gas sensors. The materials can also be used as biosensors and catalysts in the future. Originality/value: The paper presents the results of investigations relating to the synthesis of nanocomposites consisting of multiwalled carbon nanotubes and respectively Rh, Re and Pt nanocrystals and their structure and chemical composition.
3
Content available The MWCNTs-Rh Nanocomposite Obtained By The New High-Temperature Method
Dobrzańska-Danikiewicz A. D., Cichocki D., Łukowiec D.
Archives of Metallurgy and Materials
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2015
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Vol. 60, iss. 2A
1057--1063
EN
A nanocomposite was fabricated during the research undertaken, consisting of multiwalled carbon nanotubes coated with rhodium nanoparticles by the new high-temperature method being the subject of the patent claim. High quality multiwalled carbon nanotubes (MWCNTs) with the length of 100÷500 nm and the diameter of 8÷20 nm obtained in advance with Catalytic Chemical Vapour Deposition (CVD) were employed in the investigations. The nanotubes manufactured under the own research contain small amounts of metallic impurities and amorphous carbon deposits. Multiwalled carbon nanotubes functionalisation in acids was applied to deposit rhodium nanoparticles onto the surface of carbon nanotubes, and then the material was placed in a solution being a precursor of rhodium nanoparticles. The material prepared was next placed in a quartz vessel and subjected to high-temperature reduction in the atmosphere of argon to deposit rhodium nanoparticles onto the surface of multiwalled carbon nanotubes. The following examinations were performed, respectively: MWCNTs fabrication, fabrication of a CNT-NPs (Carbon NanoTube-NanoParticles) nanocomposite material; the characterisation of the materials produced including examination of the structure and morphology, and the assessment of rhodium nanoparticles distribution on the surface of carbon nanotubes. Micro- and spectroscopy techniques were employed to characterise the structure of the nanocomposites obtained.
PL
W ramach wykonanych badań wytworzono nanokompozyt składający się z wielościennych nanorurek węglowych pokrytych nanocząsteczkami rodu nową wysokotemperaturową metodą, będącą przedmiotem zgłoszenia patentowego. W badaniach wykorzystano wysokiej jakości wielościenne nanorurki węglowe MWCNTs o długości 100÷500 nm i średnicy 8÷20 nm uprzednio otrzymane w procesie katalityczno-chemicznego osadzania z fazy gazowej (CCVD). Wytworzone w ramach prac własnych nanorurki zawierają nieznaczne ilości zanieczyszczeń metalicznych i amorficznych depozytów węglowych. W celu osadzenia nanocząsteczek rodu na powierzchni nanorurek węglowych zastosowano funkcjonalizację wielościennych nanorurek węglowych w kwasach, następnie materiał umieszczono w roztworze będącym prekursorem nanocząsteczek rodu. Przygotowany materiał umieszczono w dalszej kolejności w kwarcowym naczyniu i poddano redukcji wysokotemperaturowej w atmosferze argonu w celu osadzenia nanocząsteczek rodu na powierzchni wielościennych nanorurek węglowych. Wykonane badania obejmują kolejno: wytworzenie MWCNTs, wytworzenie materiału nanokompozytowego typu nanorurki węglowe – nanocząsteczki (CNT-NPs), scharakteryzowanie wytworzonego materiału obejmujące badanie jego struktury i morfologii oraz ocenę rozmieszczenia nanocząsteczek rodu na powierzchni nanorurek węglowych. Dla scharakteryzowania struktury otrzymanych nanokompozytów zastosowano techniki mikro- i spektroskopowe.
4
Content available Microscopic and Spectroscopic Research of the MWCNTs-Re Nanocomposites
Dobrzańska-Danikiewicz A. D., Wolany W., Cichocki D., Łukowiec D.
Archives of Metallurgy and Materials
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2015
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Vol. 60, iss. 3A
2047--2051
EN
he combination of TEM research and Raman spectroscopy to characterization of MWNTs-Re nanocomposites gives a new notion about the structure and quality of materials obtained. TEM studies indicate that the functionalization method significantly influences the morphology of obtained MWCNTs-Re nanocomposites. Due to the specific spectrum recorded for the MWCNTs they can be distinguished from other forms of carbon, furthermore comparative analysis of the results at different stages of the manufacturing process confirms the covalent modification of the MWCNTs structure. The D-band intensity compared to the G-band intensity provides valuable information about the quality of the sample, in particular indicates the existence of contamination and/or the presence of structural defects. Preliminary results suggest that the high-temperature manufacturing process of MWCNTs-Re nanocomposite improves the quality of the carbon material intended for the experiment.
PL
Wykorzystanie transmisyjnej mikroskopii elektronowej oraz spektroskopii ramanowskiej, zastosowanych do scharakteryzowania nanokompozytów typu MWCNTs-Re, umożliwia określenie struktury i jakości uzyskanego materiałów. Badania TEM wskazują, że sposób funkcjonalizacji znacząco wpływa na morfologię otrzymanych nanokompozytów typu MWCNTs-Re. Charakterystyczne widmo ramanowskie uzyskane dla nanorurek wielościennych umożliwia ich identyfikację, ponadto analiza porównawcza uzyskanych wyników na różnych etapach procesu wytwórczego potwierdza kowalencyjną modyfikację struktury MWCNTs. Stosunek intensywności pasma D do intensywności pasma G informuje o jakości badanych próbek, w szczególności wskazuje na występowanie ewentualnych zanieczyszczeń i/lub obecność defektów strukturalnych. Wstępne wyniki badań wskazują, że proces wytwarzania nanokompozytu typu MWCNTs-Re z zastosowaniem wysokiej temperatury wpływa na poprawę jakości wyjściowego materiału nanorurkowego.
5
Content available Comparison of the MWCNTs-Rh and MWCNTs-Re Carbon-Metal Nanocomposites Obtained in High-Temperature
Dobrzańska-Danikiewicz A. D., Łukowiec D., Cichocki D., Wolany W.
Archives of Metallurgy and Materials
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2015
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Vol. 60, iss. 3A
2053--2060
EN
Carbon-metal nanocomposites consisting of multiwalled carbon nanotubes coated with rhodium or rhenium nanoparticles by the high-temperature method were fabricated during the research undertaken. Multiwalled carbon nanotubes fabricated by Catalytic-Chemical Vapour Deposition (CCVD) were used in the investigations. Multiwalled carbon nanotubes functionalisation in acid or in a mixture of acids was applied to deposit rhodium or rhenium nanoparticles onto the surface of carbon nanotubes, and then the material was placed in a solution being a precursor of metallic nanoparticles. The material prepared was next subjected to high-temperature reduction in the atmosphere of argon and/or hydrogen to deposit rhodium or rhenium nanoparticles onto the surface of multiwalled carbon nanotubes. The investigations performed include, respectively: fabrication of a CNT-NPs (Carbon NanoTube-NanoParticles) nanocomposite material; the characterisation of the material produced including examination of the structure and morphology, and the assessment of rhodium and/or rhenium nanoparticles distribution on the surface of carbon nanotubes. Micro- and spectroscopy techniques were employed to characterise the structure of the nanocomposites obtained.
PL
W ramach wykonanych badań wytworzono węglowo-metalowe nanokompozyty składające się z wielościennych nanorurek węglowych pokrytych nanocząsteczkami rodu lub renu metodą wysokotemperaturową. W badaniach wykorzystano wielościenne nanorurki weglowe wytworzone metodą katalityczno-chemicznego osadzania z fazy gazowej (ang.: Chemical Catalytic Vapor Deposition – CCVD). W celu osadzenia nanocząsteczek rodu lub renu na powierzchni nanorurek węglowych zastosowano funkcjonalizację wielościennych nanorurek węglowych w kwasie lub mieszaninach kwasów, następnie materiał umieszczono w roztworze będącym prekursorem nanocząsteczek metalicznych. Przygotowany materiał poddano następnie redukcji wysokotemperaturowej w atmosferze argonu i/lub wodoru w celu osadzenia nanocząsteczek rodu lub renu na powierzchni wielościennych nanorurek węglowych. Wykonane badania obejmują kolejno: wytworzenie materiału nanokompozytowego typu CNT-NPs (ang.: Carbon NanoTube-NanoParticles), scharakteryzowanie wytworzonego materiału obejmujące badanie jego struktury i morfologii oraz ocenę rozmieszczenia nanocząsteczek rodu i/lub renu na powierzchni nanorurek węglowych. Dla scharakteryzowania struktury otrzymanych nanokompozytów zastosowano techniki mikroi spektroskopowe.
6
Content available remote Various forms of platinum deposited on carbon nanotubes
Dobrzańska-Danikiewicz A. D., Wolany W., Łukowiec D., Cichocki D., Burda M.
Archives of Materials Science and Engineering
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2015
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Vol. 75, nr 2
53--62
EN
Purpose: The main purpose of the article is to present interesting forms of platinum at a nanometric scale. There are multiple fabrication methods of nanoparticles, nanowires and other forms of platinum, and the methods proposed in the article are simple and effective. They employ carbon nanotubes in the form of a so-called forest, manufactured by CVD methods and nanotubes dispergated (in a water or ethylene glycol solution) as templates for deposition of Pt nanoforms. Design/methodology/approach: Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were applied for showing the structure and morphology of platinum nanoforms deposited on carbon nanotubes, and Energy Dispersive Spectroscopy (EDS) was used for confirming the chemical composition of the analysed structures. Findings: The microscope examinations carried out with scanning electron microscopy have shown that platinum may crystallise by assuming the form of, notably, nanoparticles, nanowires and nanocubes. The structure of carbon nanotubes covered with nanoparticles of Pt at a nanoscale could have been observed by applying high-resolution transmission electron microscopy. Practical implications: Carbon nanotubes decorated with Pt nanoparticles and platinum at a nanometric scale are used as, in particular, an active layer of chemical and biochemical sensors. In addition, excellent catalytic properties of platinum are used in various industrial processes, including chemical, automotive and petroleum industry. Originality/value: Chloroplatinic acid H2PtCl6 is an input substance for producing various forms of platinum. Platinum exhibits unique physiochemical properties at a nanoscale, different than its properties at a macro scale. It was confirmed that the selected fabrication method of platinum nanoforms is effective and simple.
7
Content available remote Obtaining and description of the MWCNTs-Pd nanocomposite
Dobrzańska-Danikiewicz A. D., Cichocki D., Łukowiec D.
Archives of Materials Science and Engineering
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2015
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Vol. 74, nr 1
15--22
EN
Purpose: The main aim of the research was to produce nanocomposites consisting of carbon nanotubes coated with palladium nanoparticles and the characterisation of the obtained materials. Design/methodology/approach: High quality multiwalled carbon nanotubes (MWCNTs) with the length of 100-400 nm and the diameter of 6-25 nm obtained in advance with Catalytic Chemical Vapour Deposition (CCVD) were employed in the investigations. Carbon nanotubes–palladium nanoparticles system was fabricated by direct deposition of palladium nanoparticles, produced earlier, onto the surface of multiwall carbon nanotubes. Findings: The investigations using transmission electron microscopy together with an EDS and XPS analysis have confirmed the fact of producing an MWCNTs-Pd nanocomposite. Examinations with Raman spectroscopy have allowed to determine the difference between the degree of defects of carbon nanotubes before and after modification with palladium nanoparticles. Research limitations/implications: The presence of palladium has influence on the electrical properties of the nanocomposite, enhances sensitivity and selectivity of the CNTsNPs system in contact with the chosen chemical substance, and the result is the changing of the conductivity of nanotubes. It is a basis for the application of the studied material as an active substance of sensors of chemical/biological compounds. Originality/value: The paper presents the results of investigations relating to the synthesis of a nanocomposite material consisting of multiwalled carbon nanotubes and Pd nanoparticles and the characteristics of the material produced in terms of its structure, morphology and the distribution of Pd nanoparticles on the external surface of multiwalled carbon nanotubes and chemical composition.
8
Synteza wielościennych nanorurek węglowych metodą katalityczno-chemicznego osadzania z fazy gazowej
Dobrzańska-Danikiewicz A., Cichocki D., Wolany W., Łukowiec D.
Inżynieria Materiałowa
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2014
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Vol. 35, nr 6
477--480
PL
Metoda katalityczno-chemicznego osadzania z fazy gazowej (CCVD) umożliwia syntezę wysokiej jakości wielościennych nanorurek węglowych na masową skalę. Można wyróżnić wiele zmiennych, które wpływają w trakcie syntezy na rodzaj i postać produktu finalnego. Celem artykułu jest wyznaczenie najkorzystniejszych parametrów procesu syntezy wielościennych nanorurek węglowych metodą katalityczno-chemicznego osadzania z fazy gazowej przez odpowiedni dobór temperatury i czasu procesu syntezy oraz prędkości przepływu wodoru. Zmienne te wstępnie wyselekcjonowano jako najistotniej wpływające na postać i jakość wytworzonego nanomateriału węglowego. Do obrazowania struktury i morfologii nowo wytworzonych wielościennych nanorurek węglowych wykorzystano skaningową mikroskopię elektronową i transmisyjną mikroskopię elektronową. Badanie stopnia zdefektowania wytworzonych nanorurek węglowych wykonano metodą spektroskopii ramanowskiej.
EN
Catalytic Chemical Vapor Deposition (CCVD) method allows for the synthesis of high-quality multiwall carbon nanotubes on a mass scale. A number of variables that affect the course of the synthesis of the type and the form of the final product can be distinguished. The purpose of this paper is to present an approach for the optimisation of the synthesis process of multiwall carbon nanotubes by Catalytic Chemical Vapor Deposition by appropriately selecting the temperature and time of the synthesis process and the hydrogen flow rate. These variables are pre-selected as one which the most influencing on the character and quality of the produced carbon nanomaterial. To image the structure and the morphology of the newly formed multiwall carbon nanotubes scanning electron microscopy and transmission electron microscopy have been used. Research purity and the degree of defecting of produced carbon nanotubes were made using Raman spectroscopy.
9
Content available remote MWCNTs-Pt versus MWCNTs-Re nanocomposites manufacturing method
Dobrzańska-Danikiewicz A., Łukowiec D., Wolany W., Cichocki D.
Archives of Materials Science and Engineering
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2014
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Vol. 67, nr 1
5--13
EN
Purpose: The primary aim of the article is to compare fabrication methods and present newly fabricated MWCNTs-NPs nanocomposites whose structural components are carbon nanotubes and platinum and rhenium nanoparticles. Design/methodology/approach: The newly fabricated nanocomposites underwent STEM examinations in the bright and dark to show their structure. Raman spectroscopy examinations were carried out, as well, to confirm changes in the structure of carbon nanotubes subject to the experiments. Findings: It was found based on a comparative analysis of the structure of MWCNTs-Pt and MWCNTs-Re nanocomposites that functionalisation methods and a reduction method of precursors of selected noble elements have a significant effect on the structure and morphology of the compared carbon nanocomposites. Practical implications: Nanocomposites consisting of carbon nanotubes decorated with metal nanoparticles, including Pt and Re, possess special electrical properties and a developed specific area, which makes them particularly suitable as active elements of industrial gas sensors. The materials can also be used as biosensors and catalysts in the future. Originality/value: A comparative analysis of the following author’s methods: (i) fabrication of MWCNTs-Pt nanocomposite, which was given numerous awards at international innovation and invention exhibitions and (ii) fabrication of MWCNTs-Re nanocomposite pending patent protection.
10
Content available remote CVD synthesis of MWCNTs using Fe catalyst
Dobrzańska-Danikiewicz A. D., Pawlyta M., Łukowiec D., Cichocki D., Wolany W.
Archives of Materials Science and Engineering
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2014
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Vol. 65, nr 2
58--65
EN
Purpose: The primary aim of the article is to present the method of chemical vapour deposition (CVD) employed for fabrication of multi-walled carbon nanotubes in the presence of a catalyst. The basic growth mechanisms of carbon nanotubes are described and the nanostructural carbon materials are presented and characterised, obtained using the CVD method and an Fe catalyst deposited on a silicon substrate. Design/methodology/approach: Scanning and transmission electron microscopy was applied for illustrating the structure and morphology of the synthesised multi-walled carbon nanotubes. Findings: The microscopic examinations conducted with scanning electron microscopy and high-resolution transmission electron microscopy have confirmed the achievement of an ordered layer of multi-walled carbon nanotubes on a silicon substrate containing an Fe catalyst. Practical implications: Carbon nanotubes, due to their unique properties, can be applied in various fields of technology, especially in medicine, optics, photovoltaics and electronic engineering. CNTs are also utilised as an active layer of chemical and biochemical sensors, especially when their outer surface is decorated with nanoparticles of precious metals. Carbon nanotubes are also used as a reinforcing phase in nanocomposite materials. Originality/value: The characterisation of the chemical vapour deposition method used for synthesis of multi-walled nanotubes with a metallic catalyst with application of the EasyTube® 2000 device by FirstNano.
11
Content available remote Carbon nanotubes synthesis time versus their layer height
Dobrzańska-Danikiewicz A., Cichocki D., Łukowiec D., Wolany W.
Archives of Materials Science and Engineering
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2014
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Vol. 69, nr 1
5--11
EN
Purpose: The purpose of the article is to present an approach for the optimisation of a synthesis process of Vertically Aligned Multi-Walled Carbon Nanotubes (VAMWCNTs) with Catalytic-Chemical Vapour Deposition (CCVD) on a silicon substrate. Design/methodology/approach: Scanning and transmission electron microscopy was applied for showing the structure and morphology of the synthesised multi-walled carbon nanotubes. Findings:The article presents and characterises nanostructural carbon materials fabricated with the CCVD method using an Fe catalyst deposited on a silicon substrate. SEM and TEM examinations have confirmed that a vertical layer of a CNTs “forest” growing on a silicon substrate containing a metallic catalyst is obtained and enabled to select optimum time for their growth process. Practical implications: Vertically aligned multi-walled carbon nanotubes can be applied in numerous fields of technology, especially in scanning probes, photovoltaic cells, anisotropic conductive materials, semiconductors, membranes, chemical and biological sensors, field emitters in nanoelectronics and in molecular electronics. Originality/value: An approach is presented of optimising the synthesis time of VAMWCNTs with a metallic catalyst using CCVD with an EasyTube® 2000 device by FirstNano.
12
Content available remote Carbon nanotubes manufacturing using the CVD equipment against the background of other methods
Dobrzańska-Danikiewicz A., Łukowiec D., Cichocki D., Wolany W.
Archives of Materials Science and Engineering
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2013
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Vol. 64, nr 2
103--109
EN
Purpose: The primary purpose of the article is to present the most popular techniques of manufacturing carbon nanotubes (CNTs). The Chemical Vapour Deposition (CVD) method is described in detail with special focus laid on the universality of such technique and on economic considerations. The outcomes of investigations presenting carbon nanotubes fabricated with the EasyTube® 2000 system are also demonstrated. Design/methodology/approach: Electron microscopy was used for illustrating the structure and morphology of newly manufactured multiwalled carbon nanotubes. Findings: The microscopic examinations conducted with high-resolution transmission electron microscopy have confirmed the homogeneity, high quality and purity of the manufactured carbon nanotubes. Practical implications: Carbon nanotubes are currently valued because of their diverse applications. Depending on the structure, carbon nanotubes may act as conductors or semiconductors and such properties can be utilised in electronics. Other fields of application include optics, medicine, transportation (lightweight and robust constructions). CNTs are also utilised as elements of chemical and biochemical sensors, especially when coated with particles of precious metals (e.g. Pt, Au, Pd). Carbon nanotubes are also used as a reinforcing component in composites. Originality/value: The characterisation of carbon nanotubes fabrication methods with special consideration to the chemical vapour deposition method by means of an EasyTube 2000 device by FirstNano.
13
Content available remote Carbon nanotubes decorating methods
Dobrzańska-Danikiewicz A., Łukowiec D., Cichocki D., Wolany W.
Archives of Materials Science and Engineering
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2013
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Vol. 61, nr 2
53--61
EN
Purpose: The work is to present and characterise various methods of depositing carbon nanotubes with nanoparticles of precious metals, and also to present the results of own works concerning carbon nanotubes coated with platinum nanoparticles. Design/methodology/approach: Electron transmission and scanning microscopy has been used for imaging the structure and morphology of the nanocomposites obtained and the distribution of nanoparticles on the surface of carbon nanotubes. Findings: The studies carried out with the HRTEM and SEM techniques have confirmed differences in morphology, homogeneity and density of depositing platinum nanoparticles on the surface of carbon nanotubes and its structure. Research limitations/implications: The studies conducted pertained to the process of decorating carbon nanotubes with platinum nanoparticles. Further works are planned aimed at extending the application scope of the newly developed methodology to include the methods of nanotubes decorating with the nanoparticles of other precious metals (mainly palladium and rhodium). Practical implications: CNTs-NPs (Carbon NanoTube-NanoParticles) composites can be used as the active elements of sensors featuring high sensitivity, fast action, high selectivity and accuracy, in particular in medicine as cholesterol and glucoses sensors; in the automotive industry for the precision monitoring of working parameters in individual engine components; in environmental conservation to examine CO2, NOx, and CH4 concentrations and for checking leak-tightness and detecting hazardous substances in household and industrial gas installations. Originality/value: The comprehensive characterisation of the methods employed for fabricating nanocomposites consisting of carbon nanotubes deposited with Pt, Pd, Rh, Au, Ag nanoparticles with special consideration to the colloidal process.
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