Erratum: “Seed layer technique for high quality epitaxial manganite films” [AIP Advances 6, 085109 (2016)]

No abstract available

A Modular Stand-Alone Photocatalytic Reactor for Waste Water Purification: The HPSolar Project

In this work we present the construction and performances of a photocatalytic reactor developed for the HPSolar project, the purpose of this reactor is the treatment of water in order to remove pollutants like drugs or pesticides that are not removed effectively by present water treatments. The reactor is modular and composed by multiple elementary cells where the photocatalyst is a thin layer of tungsten trioxide biased positively with respect to a metallic cathode; this polarization is switched periodically in order to restore the functionality of the anode. The cells are completely self-reliant because are powered by four solar cells laying behind the semi-transparent anode while a microcontroller integrated into each cell applies the biasing cycles. The abatement measurements on atenolol and carbamazepine show that this device can remove 70% of the drugs from a sample of water within 5 and 7 hours respectively

Towards enhanced sodium storage of anatase TiO2: Via a dual-modification approach of Mo doping combined with AlF3coating

Recent studies on anatase TiO2 have demonstrated its capability of performing as an anode material for sodium-ion batteries (SIBs) even though, due to poor conductivity, realistic applications have not yet been foreseen. In order to try to address this issue, herein, we shall introduce a cost effective and facile route based on the co-precipitation method for the synthesis of Mo-doped anatase TiO2 nanoparticles with AlF3 surface coating. The electrochemical measurements demonstrate that the Mo-doped anatase TiO2 nanoparticles deliver an 3c40% enhanced reversible capacity compared to pristine TiO2 (139.8 vs. 100.7 mA h g-1 at 0.1 C after 50 cycles) due to an improved electronic/ionic conductivity. Furthermore, upon AlF3 coating, the overall system can deliver a much higher reversible capacity of 178.9 mA h g-1 ( 3c80% increase with respect to pristine TiO2) with good cycling stability and excellent rate capabilities of up to 10 C. The experimental results indicate that the AlF3 surface coating could indeed effectively reduce the solid electrolyte interfacial resistance, enhance the electrochemical reactivity at the surface/interface region, and lower the polarization during cycling. The improved performance achieved using a cost-effective fabrication approach makes the dually modified anatase TiO2 a promising anode material for high-performance SIBs. This journal i

Transient optical symmetry breaking for ultrafast broadband dichroism in plasmonic metasurfaces

Ultrafast nanophotonics is an emerging research field aimed at the development of nanodevices capable of light modulation with unprecedented speed. A promising approach exploits the optical nonlinearity of nanostructured materials (either metallic or dielectric) to modulate their effective permittivity via interaction with intense ultrashort laser pulses. Although the ultrafast temporal dynamics of such nanostructures following photoexcitation has been studied in depth, sub-picosecond transient spatial inhomogeneities taking place at the nanoscale have been overlooked so far. Here, we demonstrate that the inhomogeneous spacetime distribution of photogenerated hot carriers induces a transient symmetry breaking in a highly symmetric plasmonic metasurface. The process is fully reversible and results in a broadband transient dichroism with a recovery of the initial isotropic state in less than 1 ps, overcoming the speed bottleneck caused by slower (electron–phonon and phonon–phonon) relaxation processes. Our results pave the way to ultrafast dichroic devices for high-speed modulation of light polarization

Seed layer technique for high quality epitaxial manganite films

We introduce an innovative approach to the simultaneous control of growth mode and magnetotransport properties of manganite thin films, based on an easy-to-implement film/substrate interface engineering. The deposition of a manganite seed layer and the optimization of the substrate temperature allows a persistent bi-dimensional epitaxy and robust ferromagnetic properties at the same time. Structural measurements confirm that in such interface-engineered films, the optimal properties are related to improved epitaxy. A new growth scenario is envisaged, compatible with a shift from heteroepitaxy towards pseudo-homoepitaxy. Relevant growth parameters such as formation energy, roughening temperature, strain profile and chemical states are derived

Binder-free nanostructured germanium anode for high resilience lithium-ion battery

reserved21The development and the characterization of a nanostructured binder-free anode for lithium-ion batteries exploiting the germanium high theoretical specific capacity (1624 mAh g−1 for Li22Ge5 alloy) is herein presented. This anode secures remarkable performances in different working conditions attaining a 95% capacity retention at 1C (i.e., 1624 mA g−1) after 1600 cycles at room temperature and a specific capacity of 1060 mAh g−1 at 10C and 450 mAh g−1 at 60C. The nanostructured binder-free germanium-based anode shows also strong resilience in terms of temperature tests, being it tested from -30 °C to +60 °C. Indeed, the specific capacity remains unaltered from room temperature up to +60 °C, while at 0 °C the cell is still retaining 85% of its room temperature capacity. In a full-cell configuration with LiFePO4 as cathode, the Ge anode showed a stable specific capacity above 1300 mAh g−1 for 35 cycles at C/10. Concerning the fabrication procedure, a two-step realization process is applied, where a Plasma Enhanced Chemical vapor Deposition (PECVD) is employed to grow a germanium film on a molybdenum substrate followed by hydrofluoric acid (HF) electrochemical etching, the latter having the scope of nanostructuring the Ge film. Finally, compositional, morphological, and electrochemical characterizations are reported to fully investigate the properties of the binder-free nanostructured germanium anode here disclosed.restrictedFugattini, S.; Gulzar, U.; Andreoli, A.; Carbone, L.; Boschetti, M.; Bernardoni, P.; Gjestila, M.; Mangherini, G.; Camattari, R.; Li, T.; Monaco, S.; Ricci, M.; Liang, S.; Giubertoni, D.; Pepponi, G.; Bellutti, P.; Ferroni, M.; Ortolani, L.; Morandi, V.; Vincenzi, D.; Zaccaria, R. ProiettiFugattini, S.; Gulzar, U.; Andreoli, A.; Carbone, L.; Boschetti, M.; Bernardoni, P.; Gjestila, M.; Mangherini, G.; Camattari, R.; Li, T.; Monaco, S.; Ricci, M.; Liang, S.; Giubertoni, D.; Pepponi, G.; Bellutti, P.; Ferroni, M.; Ortolani, L.; Morandi, V.; Vincenzi, D.; Zaccaria, R. Proiett

Binder-free nanostructured germanium anode for high resilience lithium-ion battery

The development and the characterization of a nanostructured binder-free anode for lithium-ion batteries exploiting the germanium high theoretical specific capacity (1624 mAh g(-1) for Li22Ge5 alloy) is herein presented. This anode secures remarkable performances in different working conditions attaining a 95% capacity retention at 1C (i.e., 1624 mA g(-1)) after 1600 cycles at room temperature and a specific capacity of 1060 mAh g(-1) at 10C and 450 mAh g(-1) at 60C. The nanostructured binder-free germanium-based anode shows also strong resilience in terms of temperature tests, being it tested from-30C to +60C. Indeed, the specific capacity remains unaltered from room temperature up to +60C, while at 0C the cell is still retaining 85% of its room temperature capacity. In a full-cell configuration with LiFePO4 as cathode, the Ge anode showed a stable specific capacity above 1300 mAh g(-1) for 35 cycles at C/10. Concerning the fabrication procedure, a two-step realization process is applied, where a Plasma Enhanced Chemical vapor Deposition (PECVD) is employed to grow a germanium film on a molybdenum substrate followed by hydrofluoric acid (HF) electrochemical etching, the latter having the scope of nanostructuring the Ge film. Finally, compositional, morphological, and electrochemical characterizations are reported to fully investigate the properties of the binder-free nanostructured germanium anode here disclosed