Publications by Alfonso Baldereschi

Adsorption of HPDX and CaHPOx (x=1, ...,4) molecules on anatase TiO2 (001) surfaces

perform DFT calculations within the COSMO framework to study the adsorption properties of the CaHPOx (x = 1,...,4) phosphate family, and of the related HPOx acids, on a paradigmatic anatase (001) surface. Of particular interest is CaHPO4, a precursor of hy ...

ELSEVIER SCIENCE BV2019

Steering the Chemistry of Carbon Oxides on a NiCu Catalyst

Alfonso Baldereschi, Michele Rizzi

In the perspective of a sustainable energy economy, CO2 reduction is attracting increasing attention as a key Step toward the synthesis of fuels and valuable chemicals. A possible strategy to develop novel conversion catalysts consists in mimicking reactio ...

Amer Chemical Soc2013

Enhancing Hydrophilicity of Anatase TiO2 Surfaces by Deposition of Alkaline Earths: The Case of Ca

Alfonso Baldereschi, Michel Posternak

We show with DFT calculations within the COSMO framework that the wetting energy of clean or hydroxylated anatase TiO2 surfaces is strongly enhanced by Ca deposition at low coverage. Two mechanisms contribute to this behavior: the ionic character of Ca ads ...

Amer Chemical Soc2013

Tailoring Bimetallic Alloy Surface Properties by Kinetic Control of Self-Diffusion Processes at the Nanoscale

Alfonso Baldereschi, Michele Rizzi

Achieving control of the nanoscale structure of binary alloys is of paramount importance for the design of novel materials with specific properties, leading to, for example, improved reaction rates and selectivity in catalysis, tailored magnetic behavior i ...

Amer Chemical Soc2012

Imaging and characterization of activated CO2 species on Ni(110)

Alfonso Baldereschi, Michele Rizzi

By means of a joint experimental and theoretical approach we provide single molecule imaging and characterization of CO2 on Ni(110), chemisorbed with high charge transfer from the substrate in an activated state that plays a crucial role in the hydrogenati ...

2010

Supramolecular Self-Assembly Driven by Electrostatic Repulsion: The 1D Aggregation of Rubrene Pentagons on Au(111)

Alfonso Baldereschi, Wolf-Dieter Schneider, Massimiliano Stengel

At present, organic molecules are among the best candidate "building blocks" for the construction of self-assembling nanoscale devices based on metal substrates. Control of the formation of specific patterns In the submonolayer regime is usually achieved b ...

2010

Role of Adsorbed H, C, O, and CO on the Atomic Structure of Free and MgO(100)-Supported Ir-4 Clusters: An ab Initio Study

Alfonso Baldereschi, Zeljko Sljivancanin, Vladan Stevanovic

We applied density functional theory based on ultrasoft pseudopotentials to study the structural properties of Ir-4 clusters both in the gas phase and adsorbed on a MgO(100) surface. To resolve the discrepancy between experimental data which suggest a tetr ...

2010

Hydrogen-Assisted Transformation of CO2 on Nickel: The Role of Formate and Carbon Monoxide

Alfonso Baldereschi, Michele Rizzi

The nanoscale description of the reaction pathways and of the role of the intermediate species involved in a chemical process is a crucial milestone for tailoring more active, stable, and cheaper catalysts, thus providing "reaction engineering" capabilitie ...

2010

Transition from Mn4+ to Mn3+ induced by surface reconstruction at lambda-MnO2(001)

Alfonso Baldereschi, Zeljko Sljivancanin

Structural and electronic properties of the lambda-MnO2(001) surface are investigated applying density functional theory approach. The calculations show that all Mn ions at unreconstructed smooth surface preserve the +4 oxidation state observed in the bulk ...

2010

Effect of adsorbed H atoms on magnetism in monoatomic Fe wires at Ir(100)

Alfonso Baldereschi, Zeljko Sljivancanin

By means of ab initio calculations based on density-functional theory we demonstrate that magnetism in monoatomic Fe wires deposited on nanostructured Ir(100) surface can be tuned by their functionalization with hydrogen. The pristine monoatomic Fe wires d ...

2010

Dissociation of Water on Anatase TiO2 Nanoparticles: the Role of Undercoordinated Ti Atoms at Edges

Alfonso Baldereschi, Michel Posternak

We show with DFT calculations that hydroxyl formation on anatase TiO2 from dissociation of water molecules is strongly enhanced by a nanostructured state of the oxide, involving the occurrence of complexes consisting of undercoordinated 4-fold Ti-2-fold O ...

2009

Carbon dioxide hydrogenation on Ni(110)

Alfonso Baldereschi

We demonstrate that the key step for the reaction of CO2 with hydrogen on Ni(110) is a change of the activated molecule coordination to the metal surface. At 90 K, CO2 is negatively charged and chemically bonded via the carbon atom. When the temperature is ...

2008

Interaction of carbon dioxide with Ni(110): A combined experimental and theoretical study

Alfonso Baldereschi

We present a combined experimental and theoretical study of the CO2 interaction with the Ni(110) surface. Photoelectron spectroscopy, temperature-programmed desorption, and high-resolution electron energy loss spectroscopy measurements are performed at dif ...

2007

Local work function Moire pattern on ultrathin ionic films: NaCl on Ag(100)

Alfonso Baldereschi, François Patthey, Wolf-Dieter Schneider, Massimiliano Stengel, Marina Pivetta

2005