Wyniki wyszukiwania - BazTech

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Textural, surface, thermal and sorption properties of the functionalized activated carbons and carbon nanotubes

Nowicki P., Szymanowski W., Pietrzak R.

Polish Journal of Chemical Technology

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2015

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Vol. 17, nr 4

120--127

EN

Two series of functionalised carbonaceous adsorbents were prepared by means of oxidation and nitrogenation of commercially available activated carbon and multi-walled carbon nanotubes. The effect of nitrogen and oxygen incorporation on the textural, surface, thermal and sorption properties of the adsorbents prepared was tested. The materials were characterized by elemental analysis, low-temperature nitrogen sorption, thermogravimetric study and determination of the surface oxygen groups content. Sorptive properties of the materials obtained were characterized by the adsorption of methylene and alkali blue 6B as well as copper(II) ions. The final products were nitrogen- and oxygen-enriched mesoporous adsorbents of medium-developed surface area, showing highly diverse N and O-heteroatom contents and acidic-basic character of the surface. The results obtained in our study have proved that through a suitable choice of the modification procedure of commercial adsorbents it is possible to produce materials with high sorption capacity towards organic dyes as well as copper(II) ions.

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Węgle aktywne jako materiał elektrodowy dla kondensatorów elektrochemicznych

Nowicki P., Wachowska H.

Wiadomości Chemiczne

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2009

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[Z] 63, 5-6

461-476

EN

Electrochemical capacitors (also known as supercapacitors, ultracapacitors or electric double-layer capacitors) have been extensively investigated at a number of research centres in the world. The main reason of this interest is the possibility of their use as an alternative or complement to other electric energy storage or generation devices, e.g. batteries or fuel cells as well as their potential applications in many fields including surge-power delivery devices for electric vehicles, backup-power storage for calculators, starting power for fuel cells, etc. [1]. Research concerning electrochemical capacitors is presently divided into two main areas: (a) the redox supercapacitors (also called pseudocapacitors) and (b) the electrochemical double layer capacitors (EDLC) [2]. Development of electrochemical capacitors is connected with a search of optimal electrode materials able to a high, efficient accumulating of electrical energy, high dynamic of charge exchange with a simultaneous long durability [3]. The most widely used materials for electrochemical capacitors are active carbons. This is due to their unique physico-chemical properties such as: high electrical and thermal conductivity, low density, high corrosion resistance, well developed surface area, controlled porosity as well as availability and relatively low cost [2, 4]. This paper presents the review of literature on the influence of the physico-chemical properties of active carbons on their capacitance parameters. Much attention has been paid to the redox supercapacitors.

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Modyfikowane węgle aktywne : otrzymywanie oraz perspektywiczne kierunki ich wykorzystania

Nowicki P., Wachowska H.

Wiadomości Chemiczne

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2008

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[Z] 62, 11-12

999-1016

EN

The attractive properties of active carbons are determined by the well-developed surface area and the type, number and mode of bonding of different heteroatoms (oxygen, sulphur, nitrogen, boron, phosphorus, chlorine) with the carbon surface [3-16]. Recently, much attention has been devoted to oxygen and/or nitrogen-enriched active carbons because of a wide gamut of their applications: for adsorption of compounds of acidic character such as SO2, H2S, NOx, CO2 from the gas phase [77-90] or for adsorption of metal ions [96-100]. Modified active carbons are also very effective in removal of many organic compounds, such as aromatic and aliphatic amines or phenol and its derivatives [101-107]. Of particular importance is the application of these carbons for production of electrodes in electrochemical capacitors in order to increase their capacity [21, 61, 117-121]. This article presents a survey of literature devoted to methods of synthesis and application of modified active carbons. A special emphasis was placed on the method of preparation nitrogen-enriched active carbons.