Université de Neuchâtel

Highways and subways : a story of fungi and bacteria in soils

Simon, Anaële ; Junier, Pilar (Dir.) ; Verrecchia, Eric P. (Codir.)

Thèse de doctorat : Université de Neuchâtel, 2016.

Traditionnellement, bactériologues et mycologues mènent leurs recherches séparément, et ce malgré le fait que bactéries et champignons coexistent dans pratiquement tous les écosystèmes. Parmi les nombreuses interactions qui peuvent avoir lieu entre champignons et bactéries, cette thèse étudie les autoroutes fongiques, une interaction dans laquelle les bactéries sont capables de se...

Université de Neuchâtel

Improvement of the structural and chemical properties of a commercial activated carbon for its application in electrochemical capacitors

Lota, G. ; Centeno, Teresa A. ; Frackowiak, E. ; Stoeckli, Fritz

In: Electrochimica Acta, 2008, vol. 53, no. 5, p. 2210-2216

The present paper shows that the performance of an inexpensive activated carbon used in electrochemical capacitors can be significantly enhanced by a simple treatment with KOH at 850 °C. The changes in the specific surface area, as well as in the surface chemistry, lead to high capacitance values, which provide a noticeable energy density. The KOH-treatment of a commercial activated carbon...

Université de Neuchâtel

The role of textural characteristics and oxygen-containing surface groups in the supercapacitor performances of activated carbons

Centeno, Teresa A. ; Stoeckli, Fritz

In: Electrochimica Acta, 2006, vol. 52, no. 2, p. 560-566

It is suggested that the specific capacitance C0 of activated carbons at low current densities (d ~ 1 mA cm−2) consists, to a good first approximation, of two contributions. For the H2SO4 electrolyte they correspond to approximately 0.080 F m−2 from the total accessible surface area and an additional pseudo-capacitance of 63 F...

Université de Neuchâtel

Performance of mesoporous carbons derived from poly(vinyl alcohol) in electrochemical capacitors

Fernández, J. A. ; Morishita, T. ; Toyoda, M. ; Inagaki, M. ; Stoeckli, Fritz ; Centeno, Teresa A.

In: Journal of Power Sources, 2008, vol. 157, no. 1-3, p. 675-679

The present work shows that mesoporous materials obtained by the carbonization of mixtures of poly(vinyl alcohol) with magnesium citrate are very promising candidates for electrodes in supercapacitors. Their high performance arises essentially from a double-layer mechanism through the extent of the total surface area and one obtains at low current density (1 mA cm−2) values as high...

Université de Neuchâtel

Correlation between capacitances of porous carbons in acidic and aprotic EDLC electrolytes

Centeno, Teresa A. ; Hahn, M. ; Fernández, J. A. ; Kötz, R. ; Stoeckli, Fritz

In: Electrochemistry Communications, 2007, vol. 9, no. 6, p. 1242-1246

A study based on a total of 41 nanoporous carbons shows that there exists a good correlation between the limiting gravimetric capacitances Co at low current densities j (1 mA cm −2 ) measured in aprotic (1 M (C2H5)4NBF4 in acetonitrile) and in acidic (2 M aqueous H2SO4) electrolytes. The comparison of the...

Université de Neuchâtel

Structural characterization of submonolayer C/Al(111)

Scalese, S. ; Agostino, R. G. ; Hayoz, J. ; Naumovic, D. ; Fasel, Roman ; Aebi, Philipp ; Schlapbach, Louis

In: Surface Science, 1998, vol. 395, no. 1, p. 120-129

We report on the adsorption of atomic C in submonolayer coverages on the Al(111) surface. The local order at the surface is studied for different thermal treatments by means of full-heimispherical X-ray photoelectron diffraction. Deposition at room temperature results in disordered C adsorption while an ordering process takes place after annealing above 475 K. We depict the structure of the...

Université de Neuchâtel

Aspects of the synthesis and characterization of diamond and diamond like carbon films

Alers, Paul ; De Rooij, Nicolaas-F. (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2007 ; Th. 1952.

La présente thèse est le résultat de 15 ans d’efforts continus. Débuté en 1991, le travail de recherche s’est achevé en 2005 avec une publication finale. Le contenu de la thèse est composé de parties introductives - pour offrir au lecteur une entrée en matière sur le sujet à traiter ultérieurement - et d’articles publiés par l’auteur. A ce stade, l’auteur souhaiterait...