Phase Properties of Different HfO2 Polymorphs: A DFT-Based Study

none4Background: Hafnium Dioxide (HfO2) represents a hopeful material for gate dielectric thin films in the field of semiconductor integrated circuits. For HfO2, several crystal structures are possible, with different properties which can be difficult to describe in detail from an experimental point of view. In this study, a detailed computational approach has been shown to present a complete analysis of four HfO2 polymorphs, outlining the intrinsic properties of each phase on the basis of atomistic displacements. Methods: Density functional theory (DFT) based methods have been used to accurately describe the chemical physical properties of the polymorphs. Corrective Hubbard (U) semi-empirical terms have been added to exchange correlation energy in order to better reproduce the excited-state properties of HfO2 polymorphs. Results: the monoclinic phase resulted in the lowest cohesive energy, while the orthorhombic showed peculiar properties due to its intrinsic ferroelectric behavior. DFT + U methods showed the different responses of the four polymorphs to an applied field, and the orthorhombic phase was the least likely to undergo point defects as oxygen vacancies. Conclusions: The obtained results give a deeper insight into the differences in excited states phenomena in relation to each specific HfO2 polymorph.openEmiliano Laudadio, Pierluigi Stipa, Luca Pierantoni, Davide MencarelliLaudadio, Emiliano; Stipa, Pierluigi; Pierantoni, Luca; Mencarelli, David

Molecular dynamics simulations of quinine encapsulation into biodegradable nanoparticles: A possible new strategy against Sars-CoV-2

A new coronavirus disease, SARS-CoV-2, has spread into a global pandemic in December 2019. Since no specific therapeutic drugs for treating COVID-19 have been approved by FDA, recent studies suggest that the known antimalarial quinine and its derivatives (chloroquine and hydroxychloroquine) inhibit receptor binding of the viral particles and inhibits the strong “cytokine storm”, which is the main cause of death among infected patients. In particular, the natural alkaloid quinine has shown to possess a better safety profile and greater tolerability compared to its derivatives. Dosage optimization of quinine is still necessary as the currently available dosage forms have controversial pharmacokinetics and safety profiles. Therefore, repurposing quinine dosage forms to improve its pharmacokinetics and safety profile may be necessary to support its use against SARS-CoV-2. In this context, biodegradable/biocompatible polymeric nanoparticles may provide a safe site-specific and controlled quinine delivery, reducing the frequency of drug administration and the dose. In this study, a full atomistic molecular dynamics simulation approach has been used to investigate the use of poly-(glycolic acid) and poly-(lactic acid) and their copolymer poly-(lactic-co-glycolic acid) as potential delivery systems for lipophilic quinine to get insights into the mechanism of quinine encapsulation and release at the atomic/molecular level

Depth Distribution of Spin-Labeled Liponitroxides within Lipid Bilayers: A Combined EPR and Molecular Dynamics Approach

The distribution in an egg\u2013phosphatidylcholine bilayer of a series of spin-labeled nitroxides, potentially useful as targeted antioxidants, has been investigated using molecular dynamics (MD) simulations. The in silico method has been tested at first for a series of n-doxyl-phosphocholine-doped bilayers, with the doxyl moiety located at different positions (n) of the lipid chain, in analogy to electron paramagnetic resonance (EPR) spin labeling and other MD studies. As a result, a novel calibration curve has been obtained, suitable to determine the absolute membrane penetration depth of any paramagnetic solute from EPR measurements. A second series of MD simulations was then carried out on the newly synthesized series of liponitroxides (NOXs) recently tested as antioxidants against the lipid peroxidation of polyunsaturated fatty acids in membranes: their penetration depths, as determined by EPR in phosphatidylcholine liposomes, were correlated with their antioxidant efficacy. In these NOXs, a glycerol moiety is esterified with a carboxy derivative of a pyrroline nitroxide and one or two oleic acid residues. A very good agreement between the EPR experimental results and those from the current MD simulations indicates that the short distance of the nitroxide moiety from the fatty acid double bonds has been now definitively assessed; moreover, it indicates that our MD methodology could be successfully employed in the absence of nonparamagnetic species

Amidinoquinoxaline-Based Nitrones as Lipophilic Antioxidants

The potential of nitrones (N-oxides) as therapeutic antioxidants is due to their ability to counteract oxidative stress, mainly attributed to their action as radical scavengers toward C- and O-centered radicals. Among them, nitrones from the amidinoquinoxaline series resulted in interesting derivatives, due to the ease with which it is possible to introduce proper substituents within their structure in order to modulate their lipophilicity. The goal is to obtain lipophilic antioxidants that are able to interact with cell membranes and, at the same time, enough hydrophilic to neutralize those radicals present in a water compartment. In this work, the antioxidant efficacy of a series of amidinoquinoxaline nitrones has been evaluated regarding the oxidation of 2-deoxyribose and lipid peroxidation. The results have been rationalized on the basis of the different possible mechanisms involved, depending on some of their properties, such as lipophilicity, the ability to scavenge free radicals, and to undergo single electron transfer (SET) reactions.Fil: Gruber, Nadia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Orelli, Liliana Raquel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Minnelli, Cristina. Università Politecnica delle Marche; ItaliaFil: Mangano, Luca. F. Hoffmann-la Roche Ag; SuizaFil: Laudadio, Emiliano. Università Politecnica delle Marche; ItaliaFil: Mobbili, Giovanna. Università Politecnica delle Marche; ItaliaFil: Stipa, Pierluigi. Università Politecnica delle Marche; Itali

An Overview of the Sustainable Recycling Processes Used for Lithium-Ion Batteries

first_pagesettingsOrder Article Reprints Open AccessReview An Overview of the Sustainable Recycling Processes Used for Lithium-Ion Batteries by Daniele Marchese 1,*ORCID,Chiara Giosuè 2,*ORCID,Antunes Staffolani 3,4,5ORCID,Massimo Conti 6,Simone Orcioni 6,Francesca Soavi 3,4,5ORCID,Matteo Cavalletti 1 andPierluigi Stipa 2ORCID 1 MIDAC S.p.A., Via Alessandro Volta 2, Soave, 37038 Verona, Italy 2 Department of Science and Engineering of Matter, Environment and Urban Planning (SIMAU), Polytechnic University of Marche, INSTM Research Unit, 60131 Ancona, Italy 3 Department of Chemistry “Giacomo Ciamician”, Alma Mater Studiorum University of Bologna, 40126 Bologna, Italy 4 ENERCube, Centro Ricerche Energia, Ambiente e Mare, Centro Interdipartimentale per la Ricerca Industriale Fonti Rinnovabili, Ambiente, Mare ed Energia (CIRI-FRAME)—Alma Mater Studiorum University of Bologna, Viale Ciro Menotti, 48, 48122 Marina di Ravenna, Italy 5 National Reference Center for Electrochemical Energy Storage (GISEL)—INSTM, Via G. Giusti 9, 50121 Firenze, Italy 6 Department of Information Engineering (DII), Polytechnic University of Marche, INSTM Research Unit, 60131 Ancona, Italy * Authors to whom correspondence should be addressed. Batteries 2024, 10(1), 27; https://doi.org/10.3390/batteries10010027 Submission received: 25 November 2023 / Revised: 21 December 2023 / Accepted: 6 January 2024 / Published: 11 January 2024 (This article belongs to the Special Issue Toward Next-Generation Rechargeable Lithium-Ion Batteries: Current Status and Future Prospects) Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract Lithium-ion batteries (LIBs) can play a crucial role in the decarbonization process that is being tackled worldwide; millions of electric vehicles are already provided with or are directly powered by LIBs, and a large number of them will flood the markets within the next 8–10 years. Proper disposal strategies are required, and sustainable and environmental impacts need to be considered. Despite still finding little applicability in the industrial field, recycling could become one of the most sustainable options to handle the end of life of LIBs. This review reports on the most recent advances in sustainable processing for spent LIB recycling that is needed to improve the LIB value chain, with a special focus on green leaching technologies for Co-based cathodes. Specifically, we provide the main state of the art for sustainable LIB recycling processes, focusing on the pretreatment of spent LIBs; we report on Life Cycle Assessment (LCA) studies on the usage of acids, including mineral as well as organic ones; and summarize the recent innovation for the green recovery of valuable metals from spent LIBs, including electrochemical methods. The advantage of using green leaching agents, such as organic acids, which represent a valuable option towards more sustainable recycling processes, is also discussed. Organic acids can, indeed, reduce the economic, chemical, and environmental impacts of LIBs since post-treatments are avoided. Furthermore, existing challenges are identified herein, and suggestions for improving the effectiveness of recycling are defined

Recent contributions of EPR to nitrone and nitroxide chemistry

The present contribution provides an overview of the latest research studies in which Nitrones and Nitroxides are involved in the applications of Electron Paramagnetic Resonance Spectroscopy (EPR) in different fields. Due to the free radical nature of Nitroxides (Aminoxyls), their use in EPR investigations is rather straightforward, while for Nitrones (N-oxides) it relies instead on their use as ‘‘radical scavengers’’, and/or by their use in the EPR Spin Trapping technique. Since the chemistry of both Nitrones and Nitroxides have been extensively described elsewhere, this contribution would only represent an update on some of their most recent application involving EPR spectroscopy

A Multi-Step procedure for evaluating the EPR parameters of Indolinonic Aromatic Aminoxyls: a combined DFT and spectroscopic study

A DFT study on indolinonic aromatic aminoxyls has been carried out at different levels of theory. The comparison with previous experimental data from ENDOR, X-rays and PND (polarized neutron diffraction) techniques confirms that such a computational approach represents an important aid for understanding the properties of this class of aminoxyls such as hyperfine coupling constants (hfcc), isotropic g-factors, spin density distributions and geometries. At first, a model compound was studied with different model chemistries; B1LYP, B3LYP and PBE0 hybrid functionals were employed in conjunction with various medium to large size basis sets. The study outlines that none of the model chemistries considered is able to correctly describe the EPR features of these radicals by itself. For this reason, by taking into account a compromise between accuracy and computational cost, a multi-step procedure was checked over a homogeneous series of indolinonic aminoxyls and then proposed

Features of some Aromatic Heterocyclic Nitrones and Nitroxides

Invited keynote oral contributio