GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    In: Diamond and Related Materials, Elsevier BV, Vol. 122 ( 2022-02), p. 108810-
    Type of Medium: Online Resource
    ISSN: 0925-9635
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2022
    detail.hit.zdb_id: 2019690-8
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Online Resource
    Online Resource
    Trans Tech Publications, Ltd. ; 2016
    In:  Materials Science Forum Vol. 879 ( 2016-11-15), p. 1387-1392
    In: Materials Science Forum, Trans Tech Publications, Ltd., Vol. 879 ( 2016-11-15), p. 1387-1392
    Abstract: Protective coatings able to provide improved tribological behavior and corrosion resistance are demanded in many industrial applications. Although hard chrome is a very effective solution and is widely used, environmental issues related to hexavalent chromium push to develop alternative treatments. Within the framework of the HardAlt European Project, electrodeposited composite coatings have been developed and main results of this investigation are reported in this work. Boron carbide micro-particles were dispersed in a Ni-P matrix under different operating conditions, in order to produce coatings with different composition and particle content. Structural and morphological characterization was performed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Mechanical properties were evaluated by micro-indentation and the tribological performance was assessed by block-on-ring tests. Electrochemical experiments were carried out to examine the corrosion behavior of the composite coatings. Interesting results were obtained for composite coatings as regards hardness values, tribological behavior and corrosion resistance, even though some improvements can be realized. However, the results presented in this work show that composite coatings may represent a promising alternative to hard chrome for selected applications and also suggestions for further investigation are gained.
    Type of Medium: Online Resource
    ISSN: 1662-9752
    URL: Issue
    Language: Unknown
    Publisher: Trans Tech Publications, Ltd.
    Publication Date: 2016
    detail.hit.zdb_id: 2047372-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Online Resource
    Online Resource
    The Electrochemical Society ; 2015
    In:  ECS Meeting Abstracts Vol. MA2015-02, No. 22 ( 2015-07-07), p. 908-908
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2015-02, No. 22 ( 2015-07-07), p. 908-908
    Abstract: A widely used method to protect steel surfaces from corrosion is the application of a sacrificial layer of a less noble metal, which undergoes preferential corrosion due to galvanic coupling. The most used material is zinc, a metal readily available and easy to apply on components presenting large areas. However, zinc is far more reactive than iron, and the thickness of material needed to effectively prevent corrosion represents an issue for some applications, such as coatings for the automotive sector or the aerospace field. A possible solution can be the alloying of zinc with a metal of the iron group, thus increasing the nobility of the layer. By doing this the corrosion potential is shifted to values closer to iron, inducing a slower consumption of the sacrificial layer. Nickel, having a suitable equilibrium potential, is the most used metal, providing an excellent corrosion protection with respect to pure zinc. The coatings obtained are times more resistant to corrosion than pure zinc and are currently studied as alternatives to cadmium. Zn–Ni alloys are reasonably easy to electrodeposit, and the plating of corrosion efficient coatings was performed in the past from acidic and alkaline electrolytes. It is well-known that the best protective properties are achieved when the alloy presents a single γ phase, a condition that can be attained by controlling properly the plating parameters and electrolyte formulation. It is interesting to point out that the plated γ phase can be a metastable structure, as the Zn–Ni phase diagram predicts lattice distributions of the Ni atoms in contrast with the experimental results. The reasons for the observed metastability and the thermodynamic properties of Zn–Ni have been elucidated previously starting from the analysis of the equilibrium conditions of the different phases. It was demonstrated that Zn–Ni electroplated alloys from an alkaline bath follow the theoretical simulations, thus validating the interpretation provided. Zn–Ni can be plated also by means of pulsed electrodeposition, a method suitable to achieve more refined microstructures and compact layers. This change in microstructure also improves the corrosion behavior and the distribution of the residual stresses. Zn–Ni alloys having compositions in the range 14–18 wt-% are electrodeposited using direct current DC and pulse current PC in a cyanide-free alkaline electrolyte. Homogeneous and compact layers, suitable for corrosion protection, are obtained. Contrary to the common acceptance, X-ray diffraction spectra and differential scanning calorimetry thermal analysis show that the electrodeposited γ alloy by DC plating in electrolytes with complexant-additive agents has to be regarded as a metastable phase, whose atomic arrangement is different from that of the equilibrium γ intermetallic compound. A model for atomic distribution and the Gibbs free-energy function for the DC electrodeposited phase are discussed. It is found that PC deposited alloys from additive-free electrolytes present the same metastable behavior attributed to the DC plated homologues in electrolytes with complexant-additive agents. The corrosion behavior is found to be dependent on the duty cycle applied during PC deposition, as evidence of the different microstructures obtained in varying the parameters.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2015
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Online Resource
    Online Resource
    The Electrochemical Society ; 2013
    In:  ECS Meeting Abstracts Vol. MA2013-02, No. 41 ( 2013-10-27), p. 2432-2432
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2013-02, No. 41 ( 2013-10-27), p. 2432-2432
    Abstract: Abstract not Available.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2013
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    The Electrochemical Society ; 2016
    In:  ECS Meeting Abstracts Vol. MA2016-02, No. 18 ( 2016-09-01), p. 1525-1525
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2016-02, No. 18 ( 2016-09-01), p. 1525-1525
    Abstract: Galvanic displacement from fluoride containing solution is a well established technique for the deposition of metals on semiconductor substrates, with a very broad plethora of applications in the electronic, photovoltaic and MEMS industries, due to the film conformal nature and process high selectivity towards silicon surfaces. Immersion plating is able to produce very homogeneous thickness metal seeds. Particularly, Copper and Nickel were the chosen species for silicon plating due to their wide application range and variety of different exploitable properties, also in thin films engineering. Copper has a very good electrical conductivity and charge mobility, while Nickel has good electron transport properties too as well as magnetic features that are exploited in several micro- and nano-devices. Very good results have already been achieved in the past years for Copper and Nickel systems in terms of metal film homogeneity and aspect ratio. In order to have a complete substrates characterization, newly adapted plating baths were used for p-doped Silicon wafers metallization just after a suitable surface cleaning step was performed. The resulting metallic layers showed high homogeneity and high reflectivity, achieving mirror-like appearances as well as very low mean surface roughness. SEM characterization was also used to appreciate the metal layer thickness control achieved by the proposed processes, as well as gathering information about the different metals growth rate. Subsequently, X-rays photoelectrons spectroscopy has been employed to understand the surface state of Silicon, Nickel and Copper in the plated substrate; furthermore X-rays diffraction analysis was used to characterize the crystalline structure of the metallic thin films on top of the semiconductor. The collected data have been employed as input for Density Functional Theory calculations on the Nickel-Silicon and Copper-Silicon interfaces, aiming at the description of the interactions at the interfaces from an atomistic point of view.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2016
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Online Resource
    Online Resource
    The Electrochemical Society ; 2016
    In:  ECS Meeting Abstracts Vol. MA2016-02, No. 47 ( 2016-09-01), p. 3536-3536
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2016-02, No. 47 ( 2016-09-01), p. 3536-3536
    Abstract: Zinc alloys containing transition metals (Ni, Co and Fe) have attracted the attention because of their high corrosion resistance [1,2]; particularly high is the interest of ZnNi system for practical application. In addition, electrodeposition of ZnNi alloys is generally described as anomalous codeposition (Brenner [3] ). In this work ZnNi electrodeposition from ionic liquid system is studied; particular attention is paid to the formation Zn rich alloys (15-25 % Ni). The plating bath consists of 1 choline chloride: 2 ethylene glycol containing metal salts in different concentration. All the electrodepositions have been carried out at constant temperature T=70°C on steel. Codeposition of ZnNi is studied by means of potentiostatic electrodeposition. Compositional and morphological analysis are performed to evaluate the effect of the plating conditions and bath formulation. Electrochemical characterization of the solution is performed for those baths compositions allowing the formation of 𝛾 -phase ZnNi. Metastable 𝛾 -ZnNi with short-range order has been observed with XRD analysis; thermal treatment are carried out to evaluate phase reorganization. [1] R Fratesi, G Roventi. Corrosion resistance of Zn-Ni alloy coatings in industrial production, Surface and Coatings Technology. 82 (1996) 158. [2] R Ramanauskas, P Quintana, L Maldonado, R Pomés, MA Pech-Canul. Corrosion resistance and microstructure of electrodeposited Zn and Zn alloy coatings, Surface and Coatings Technology. 92 (1997) 16. [3] A Brenner. A. Electrodeposition of Alloys. Vol. 1, General Survey, Principals, and Alloys of Copper and of Silver, (1963).
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2016
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Online Resource
    Online Resource
    The Electrochemical Society ; 2015
    In:  ECS Meeting Abstracts Vol. MA2015-02, No. 10 ( 2015-07-07), p. 609-609
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2015-02, No. 10 ( 2015-07-07), p. 609-609
    Abstract: Graphene has become a promising material for many different applications, such as nanoelectronic devices, physical, chemical and biochemical sensors, transparent conductive films, clean energy scavenging and storage devices, and nanocomposite formulations. This great variety of possibilities is determined by the exceptional charge transport, optical, and mechanical properties of the material. Recently gas sensing, as a critical application in intelligent systems, is receiving increasing attention between the possible applications in both industry and academy. Sensing applications using graphene sheets as transducers have experienced a surge of activities in recent years, especially for gas sensing platforms and electrochemical sensing, because of the high electrical conductivity and high surface area of graphene. The most intriguing feature of graphene based sensors is that a proper functionalization of graphene enables enhanced selectivity and improved performances. Moreover, by combining graphene electronic and mechanical properties monolithic sensors with superior sensitivity can be developed. Despite the significant amount of work on graphene electronic devices such as the field effect transistor, its use in sensors, actuators or micro and nano-electromechanical systems (MEMS/NEMS) in general is relatively less explored. In this work the synthesis of graphene by precursor decomposition at different temperatures onto free standing electrodeposited substrates is investigated, allowing therefore to study the effects of electrochemically produced substrates onto graphene quality. The production of porous structure obtained dealloying the electrodeposited NiCu substrates will be discussed for the synthesis of porous graphene layers. The specific area of the structure obtained is therefore greatly enhanced, improving in this way the sensing capacity. The growth of good quality graphene layers is also discussed in terms of the role played by grain boundaries and diffusion at the grain boundaries. Finally, graphene coated substrates as electrodes for electrochemical sensor and the integration of graphene layers into MEMS for microsensor production will be presented.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2015
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Online Resource
    Online Resource
    Elsevier BV ; 2009
    In:  Transactions of Nonferrous Metals Society of China Vol. 19, No. 4 ( 2009-8), p. 810-813
    In: Transactions of Nonferrous Metals Society of China, Elsevier BV, Vol. 19, No. 4 ( 2009-8), p. 810-813
    Type of Medium: Online Resource
    ISSN: 1003-6326
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2009
    detail.hit.zdb_id: 2238689-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Online Resource
    Online Resource
    The Electrochemical Society ; 2017
    In:  ECS Meeting Abstracts Vol. MA2017-01, No. 8 ( 2017-04-15), p. 632-632
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2017-01, No. 8 ( 2017-04-15), p. 632-632
    Abstract: Recently, carbon nanomaterials have become a hot topic within the field of materials science because they have the potential to provide solutions to technological and environmental challenges in various areas. Among these materials, graphene is rapidly emerging as one of the most exciting materials for electro catalysts in electrochemical applications such as super-capacitors, Li-ion batteries, solar cells, and biosensors, due to its unique structure and electronic properties. Applications of graphene in biology are very appealing due to the possibility to have a conductive substrate prone to be modified to strictly interact with specific molecules if properly functionalized [1].Although a basic energy source for humans, dysfunctions in the metabolism of glucose are becoming more and more common. These metabolic diseases are called diabetes. At the beginning of the new millennium, 172 million people were affected by diabetes and, according to estimation, that number would have risen to 366 million in 2030 [2] . However, this latter number has already been reached and new estimation for 2035 foresee 595 million cases [3], with diabetes becoming the 7th cause of death [4] . In this work, deposition of graphene on thin and flexible electroplated copper surface by chemicalvapor deposition (CVD) has been researched for bottom-up glucose sensor building. Copper samples covered with graphene have then been used as electrodesin glucose sensors and their performances have been compared with that of bare copper.CVD is one of the most promising fabrication methods of graphene; this method is probably the best candidate to be used in the electronic industry, due to the high-quality and low defects layers it can yield. Electrodeposited copper substrates have been used as catalysts for the atmospheric pressure CVD process. These substrates have been used as deposited, or further processed to tailor their surface properties: for example, the effect of annealing in a reducing atmosphere and electropolishing have been researched. Graphene/FLG surface was then decorated with gold nanoparticles via immersion plating, to enhance sensor sensitivity. Finally, inkjet printing of copper oxide nanoparticles was implemented to test the properties of the so obtained nanohybrid. To assess the quality of grown graphene layers, Raman spectroscopy was employed, due to well-known graphene/FLG Raman fingerprints. Further characterization with a scanning electron microscope (SEM) and with X-ray photoemission spectroscopy (XPS) and UV photoemission spectroscopy (UPS) has been performed. [1] Sharma, N., Ojha, H., Bharadwaj, A., Pathak, D.P., Sharma, R.K., 2015. RSC Adv. 5 (66), 53381–53403. [2] Wild, S., Roglic, G., Green, A., Sicree, R. & King, H. 2004, "Global Prevalence of Diabetes: Estimates for the year 2000 and projections for 2030 ", Diabetes care, vol.27, no. 5, pp. 1047-1053. [3] http://www.expo2015.orgmagazineitlifestylediabete–tutti-i-numeri-in-italia-e-nelmondo.html [4] Tian, K., Prestgard, M. & Tiwari, A. 2014, "A review of recent advances in non-enzymatic systems", vol. 41, pp. 100-118.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2017
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Online Resource
    Online Resource
    The Electrochemical Society ; 2016
    In:  ECS Meeting Abstracts Vol. MA2016-01, No. 11 ( 2016-04-01), p. 745-745
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2016-01, No. 11 ( 2016-04-01), p. 745-745
    Abstract: Graphene, thanks to its novel properties, has proved to be a very good material for electronics applications, spacing from MEMS to biosensing technology. In the last few years chemical vapor deposition of organic precursors onto transition metal supports revealed to be a trustworthy method for high quality graphene deposition, thanks to catalytic properties of the already cited metals. In this work, we selected nickel as the suitable transition metal substrate for graphene growth via chemical vapor deposition, which has been carried out starting from a gaseous methane and hydrogen process stream. In fact, nickel-carbon interaction mechanisms are well known and suitable for the effort of controlling the quantity of organic material that is able to grow onto the metal surface. Obtained samples were analyzed by Raman spectroscopy; spectra pointed out a total absence of the D peak, whose presence is generally accounted for graphene bad transport properties due to many domain boundaries; on the other side, Raman study revealed a higher than one intensity ratio between G peak and 2D band. The succeeding step consisted in the application of the so developed methodology in order to produce graphene coated devices. We based our approach on already existing works [1,2] but tried to exploit the properties of the galvanic displacement process in order to cover monocrystalline silicon wafers with a thin nickel film. First, we tuned the displacement process in order to fit our needs, performing the plating at different times, fixing our attention to film compactness and adhesion to silicon. Then chemical vapor deposition was employed and samples were analyzed to understand the degree of reproducibility of the process. Again, Raman spectroscopy, AFM, SEM and XPS were employed in order to understand graphene quality achieved. Raman spectra were very similar to those of the freestanding nickel foils, while XPS performed onto the same substrate yielded some coherent results: in those points were the nickel signal was higher, and so carbon signal was lower, we ended up with 1.3 nm few layered graphene thickness. Recollecting graphite interplanar distances, which was roughly 0.34 nm, 3 to 4 graphene sheets were deposited. By atomic force microscopy we were able to highlight graphene sheets stacked onto the sample surface. Microstructured, polycrystalline, silicon wafer were coated by the carbonaceous layer using the same chemical vapor deposition process already explained. Raman spectroscopy was again the main characterization technique used to gather information about the deposit: the intensity ratio I(G)/I(2D) was higher than one. In conclusion, we managed to deposit good quality, few layered, graphene onto silicon substrate by using a transition metal thin film as a buffer layer for the growth. A first attempt has been made to understand if graphene layers were grown also between the metal film and silicon; this would represent a first concern towards a very cost efficient and reproducible graphene coated semiconductors. [1] D.Q. McNerny et al.; Sci. Rep. 4, 5049; DOI:10.1038/srep05049 (2014). [2] Yu Yao et al. / Energy Procedia 38 ( 2013 ) 807 – 815.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2016
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...