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Publications associées (30)

Transparent, conducting Nb:SnO2 for host-guest photoelectrochemistry

Michael Graetzel, Morgan Mertens Stefik, Nripan Mathews, Maurin Cornuz, Takashi Hisatomi

Many candidate materials for photoelectrochemical water splitting will be better employed by decoupling optical absorption from carrier transport. A promising strategy is to use multiple thin absorber layers supported on transparent, conducting materials; ...

American Chemical Society (ACS)2012

A Ga2O3 underlayer as an isomorphic template for ultrathin hematite films toward efficient photoelectrochemical water splitting

Michael Graetzel, Kevin Sivula, Nicolas Tétreault, Florian Le Formal, Maurin Cornuz, Jérémie Minh-Châu Brillet, Takashi Hisatomi

Hematite photoanodes for photoelectrochemical (PEC) water splitting are often fabricated as extremely-thin films to minimize charge recombination because of the short diffusion lengths of photoexcited carriers. However, poor crystallinity caused by structu ...

2012

Helium-vacancy cluster in a single bcc iron crystal lattice

Helena Van Swygenhoven

The properties of the cluster HenV, an iron vacancy with an increasing number of He atoms, is studied with molecular statics and molecular dynamics simulations. A study of the binding energy of the self-interstitial atom (SIA) and the He, shows that from n ...

2011

Evolution of an Oxygen Near-Edge X-ray Absorption Fine Structure Transition in the Upper Hubbard Band in alpha-Fe2O3 upon Electrochemical Oxidation

Michael Graetzel, Kevin Sivula, Artur Braun

Electrochemical oxidation of hematite (alpha-Fe2O3) nanoparticulate films at 600 mV vs Ag+/AgCl in KOH electrolyte forms a species at the hematite surface which causes a new transition in the upper Hubbard band between the Fe(3d)-O(2p) state region and the ...

American Chemical Society2011

Cadmium adsorption to mixtures of soil components: Testing the component additivity approach

Daniel Scott Alessi

The ability to predict the distribution of metals in geologic systems requires a modeling approach that can describe the competition among adsorbing surfaces for the metal of interest. In this study, we test if a component additivity (CA) surface complexat ...

2010

Influence of oxygen content on structure and properties of multi-element AlCrSiON oxynitride thin films

Alireza Karimi

Multi-element oxynitrides of type Al-Cr-Si-O-N were prepared using r.f. magnetron sputtering from Al80Cr2.5Si17.5 (at.%) target composition and O-2/(O-2+N-2) gas flow ratio between 0 and 100%. Two series of samples varying from pure nitrides to pure oxides ...

2010

Direct Observation of Impurity-Induced Magnetism in a Spin-1/2 Antiferromagnetic Heisenberg Two-Leg Spin Ladder

Shuang Wang, Siyuan Wang, Joël Mesot, Kazimierz Conder

Nuclear magnetic resonance and magnetization measurements were used to probe the magnetic features of single-crystalline Bi(Cu1-xZnx)(2)PO6 with 0 < x < 0.05 at temperatures between 2.6 K and 300 K. The simple line shape of the P-31 NMR signals of the pris ...

American Physical Society2010

Anisotropic photocatalytic properties of hematite

Michael Graetzel, Ilkay Cesar

Hematite is a semiconducting mineral with a role in natural photoelectrochemical processes, and has been studied from the viewpoint of solar energy utilization. Hematite is an anisotropic conductor, with faster conduction parallel to (001) planes. Flatband ...

2009

WO3-Fe2O3 Photoanodes for Water Splitting: A Host Scaffold, Guest Absorber Approach

Michael Graetzel, Kevin Sivula, Florian Le Formal

Solar hydrogen production via watersplitting with hematite (Fe2O3) has been limited by poor light absorption and a small hole diffusion length. These drawbacks can be overcome by using a high-surface-area host to support a thin layer of hematite-allowing p ...

2009

Long-Range Electron Transfer across Cytochrome-Hematite (alpha-Fe2O3) Interfaces

Kevin M. Rosso, Nicholas Wigginton

Electrochemical scanning tunneling microscopy was used to assess the distance dependence of electron transfer facilitated by a bacterial multiheme cytochrome to a single crystal iron oxide surface. We measured tunneling current-distance (I-s) profiles acro ...

2009

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