A5028889704- Catalytic Processes in Materials Science
- Catalysis and Oxidation Reactions
- Magnetism in coordination complexes
- Advanced Chemical Physics Studies
- Advanced Photocatalysis Techniques
- Electron Spin Resonance Studies
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Inorganic Fluorides and Related Compounds
- Lanthanide and Transition Metal Complexes
- Advanced NMR Techniques and Applications
- Zeolite Catalysis and Synthesis
- Luminescence Properties of Advanced Materials
- Electrocatalysts for Energy Conversion
- TiO2 Photocatalysis and Solar Cells
- Polyoxometalates: Synthesis and Applications
- Porphyrin and Phthalocyanine Chemistry
- Electronic and Structural Properties of Oxides
- Metal-Catalyzed Oxygenation Mechanisms
- Organometallic Complex Synthesis and Catalysis
- Molecular Junctions and Nanostructures
- Semiconductor materials and devices
- Glass properties and applications
- Ga2O3 and related materials
- Advanced Condensed Matter Physics
University of Turin
2015-2024
National Interuniversity Consortium of Materials Science and Technology
2008-2023
Torino e-district
2015-2021
Dutch Polymer Institute
2014
University of Antwerp
2006-2010
Centre National de la Recherche Scientifique
2009-2010
Université de Montpellier
2010
Institut Universitaire de France
2009
Sorbonne Université
2009
Laboratoire de Réactivité de Surface
2009
Here we report the investigation of magnetic relaxation and quantum coherence vanadyl phthalocyanine, VOPc, a multifunctional easy-processable potential molecular spin qubit. VOPc in its pure form (1) crystalline dispersions isostructural diamagnetic host TiOPc different stoichiometric ratios, namely VOPc:TiOPc 1:10 (2) 1:1000 (3), were investigated via multitechnique approach based on combination alternate current (AC) susceptometry, continuous wave, pulsed electron paramagnetic resonance...
Fluorine-doped titanium dioxide was prepared via sol−gel synthesis and subsequent calcination in air. The presence of fluorine the lattice induces formation reduced Ti3+ centers that localize extra electron needed for charge compensation are observed by paramagnetic resonance. Density functional theory calculations using hybrid functionals full agreement with such description. is highly localized a 3d orbital lies few tenths an volt below bottom conduction band. preparation aqueous solutions...
In the search for long-lived quantum coherence in spin systems, vanadium(IV) complexes have shown record phase memory times among molecular systems. When nuclear spin-free ligands are employed, can show at low temperature sufficiently long times, Tm, to perform operations, but their use real devices operating room is still hampered by rapid decrease of T1 caused efficient spin–phonon coupling. this work we investigated effect different coordination environments on magnetization dynamics and...
Electron Paramagnetic Resonance (EPR) techniques have been employed to investigate charge carrier trapping in the two main TiO2 polymorphs, anatase and rutile, with particular attention features of electron sites (formally Ti(3+) ions). The classic CW-EPR technique this case provides signals based on g tensor only. Nevertheless a systematic analysis obtained various cases (anatase surface bulk centers, regular defective sites) has performed providing useful guidelines field affected by some...
Practical implementation of highly coherent molecular spin qubits for challenging technological applications, such as quantum information processing or sensing, requires precise organization electronic qubit components into extended frameworks. Realization spatial control over qubit–qubit distances can be achieved by coordination chemistry approaches through an appropriate choice the building blocks. However, translating single units arrays does not guarantee a priori retention long...
We report a careful characterization of the interaction NH3 with Cu(II) sites [Cu2C4O8] paddle-wheel cornerstone HKUST-1 metallorganic framework, also known as Cu3(BTC)2. The general picture emerging from combining XRPD, EXAFS, XANES, mid- and far-IR, DRUV–vis, EPR techniques is that presence traces water has relevant consequences on effect ammonia MOF framework. adsorption dry system results in strong chemisorption distorts keeping crystallinity material. Perturbation observed upon...
A multitechnique investigation of an evaporable vanadyl spin system with long-lived quantum coherence that self-assembles on gold.
A systematic analysis of the reduced states in titanium dioxide matrix (anatase polymorph) has been performed coupling classic continuous wave electron paramagnetic resonance (CW-EPR) with advanced pulse-EPR techniques and introducing 17O magnetic isotope into solid. Reduced were originated various ways including valence induction via aliovalent elements (F, Nb) reducing treatments bare oxide surface reaction agents (H, Na) thermal annealing under vacuum consequent oxygen depletion. Two main...
The generation of surface charge carriers in N-doped TiO2 under various types irradiation has been investigated by electron paramagnetic resonance using an approach consisting scavenging migrated electrons and holes oxygen hydrogen, respectively. TiO2, which is moderately active photocatalytic processes visible light, forms and, at lower extent, due to the synergistic effect components (around 400 nm) near-infrared ones. radiation excites from intra band gap NOx– states conduction band,...
Control of spin-lattice magnetic relaxation is crucial to observe long quantum coherence in spin systems at reasonable temperatures. Such a control most often extremely difficult achieve, because the coexistence several mechanisms, that direct, Raman, and Orbach. These are not always easy relate energy states investigated system, contribution additional spin-phonon coupling phenomena mediated by intramolecular vibrations. In this work, we have effect slight changes on molecular structure...
A molecular architecture where two vanadyl-based qubits are linked together is herein described and investigated as a platform for quantum simulation.
Carbon nitride (CN) is a heterogeneous photocatalyst that combines good structural properties and broad scope. The photocatalytic efficiency of CN associated with the presence defective radical species. An accurate description states-both at local extended level-is key to develop thorough mechanistic understanding photophysics CN. In turn, this will maximise generation usage photogenerated charge carriers minimise wasteful recombination. Here influence morphology light-excitation on number...
The manipulation of carbon nitride (CN) structures is one main avenue to enhance the activity CN-based photocatalysts. Increasing efficiency photocatalytic heterogeneous materials a critical step toward realistic implementation sustainable schemes for organic synthesis. However, limited knowledge structure/activity relationship in relation subtle structural variations prevents fully rational design new materials, limiting practical applications. Here, CN structure engineered by means...
Abstract Time‐resolved EPR (TR‐EPR) demonstrates the formation of well‐defined spin triplet excitons in carbon nitride. This permits to experimentally probe extent wavefunction which delocalizes over several tri‐ s ‐triazine units. Analysis temperature dependence TR‐EPR signal reveals mobility excitons. By employing monochromatic light excitation range 430–600 nm, energy is estimated be ≈0.2 eV above conduction band edge, proving that exciton lies corresponding singlet. Comparison between...
Surface excess electrons are remarkable chemical entities that provide great opportunities for the design of new materials with precisely tuned electronic and magnetic properties. In this Account, we describe structure properties electron centers generated at surface insulating oxides. We also outline elementary mechanisms basis generation solid surfaces, setting a comparison to general problem localization in condensed media. Emphasis is given morphological aspects relative surface-trapping...
The typical activation of a fourth generation Ziegler-Natta catalyst TiCl4/MgCl2/phthalate with triethyl aluminum generates Ti(3+) centers that are investigated by multi-frequency continuous wave and pulse EPR methods. Two families isolated, molecule-like species have been identified. A comparison the experimentally derived g tensors (35,37)Cl hyperfine nuclear-quadrupole DFT-computed values suggests dominant EPR-active is located on MgCl2(110) surfaces (or equivalent MgCl2 terminations...
The selection of molecular spin qubits with a long coherence time, Tm, is central task for implementing molecule-based quantum technologies. Even if sufficiently Tm can be achieved through an efficient synthetic strategy and ad hoc experimental measurement procedures, many factors contributing to the loss still need thoroughly investigated understood. Vibrational properties nuclear spins hydrogens are two them. former plays paramount role, but detailed theoretical investigation aimed at...
We report here the synthesis of a new meso-meso (m-m) singly linked vanadyl-porphyrin dimer that crystallizes in two different pseudo-polymorphs. The single crystal continuous-wave electron paramagnetic resonance investigation evidences small but crucial isotropic exchange interaction, J, between tilted, and thus distinguishable, spin centers order 10-2 cm-1. experimental DFT studies evidence correlation J values porphyrin plane tilting angle distortion. Pulsed EPR analysis shows vanadyl...
The nature of radical defects governs the photocatalytic activity graphitic carbon nitride.
Copper-ceria mixed oxides are widely considered promising catalysts for oxidation reactions, especially when the participation of lattice oxygen is required. However, mechanistic understanding these catalytic systems still incomplete, due to their considerable complexity. In fact, copper doping ceria results in formation a significant number different interacting sites continuous evolution during processes. present study, pure and Cu-doped samples were deeply investigated through combined...
We have systematically used electron paramagnetic resonance (EPR) to understand the nature of excess centers in titanium dioxide and classify their spectroscopic features. Excess electrons TiO2 (probably most important photoactive oxide) been generated either by photoinduced charge separation or reductive treatments are stabilized solid ions which reduce Ti3+. These monitored EPR classified on basis g tensor values order amend a certain confusion present literature about this subject. In...