The Experts below are selected from a list of 858 Experts worldwide ranked by ideXlab platform

S Lancerosmendez - One of the best experts on this subject based on the ideXlab platform.

  • reusability of photocatalytic tio2 and zno nanoparticles immobilized in poly vinylidene Difluoride co trifluoroethylene
    Applied Surface Science, 2016
    Co-Authors: Sara Teixeira, Pedro Manuel Abreu Martins, S Lancerosmendez, Klaus Kuhn, Gianaurelio Cuniberti
    Abstract:

    Abstract Pollutants present in water are increasingly becoming an important public health issue. After their transportation across the sewer network they can pass through the wastewater treatment plants (WWTPs) mostly unchanged because WWTPs are not designed to remove pollutants present at trace levels. Conventional treatments are therefore ineffective. Immobilized photocatalytic systems are thus an advantage for the treatment of contaminated water, because they are ecofriendly, cost-effective and allow reusability. This work reports on TiO 2 and ZnO commercial nanoparticles immobilized in poly(vinylidene Difluoride)- co -trifluoroethylene (P(VDF-TrFE)). Nanocomposites of P(VDF-TrFE) with different concentrations of TiO 2 nanoparticles (5, 10, and 15 wt.%) and ZnO nanoparticles (15 wt.%) were produced by solvent casting and tested on the degradation of methylene blue, a model organic dye. Each nanocomposite was tested three times to assess its reusability. It is shown that increasing the photocatalyst concentration results in higher photocatalytic efficiencies; the degradation rates of 15% of TiO 2 and ZnO are similar; and the photoactivity decreases 6%, 16%, 13%, and 11% after three utilizations, for TiO 2 5%, TiO 2 10%, TiO 2 15%, and ZnO 15%, respectively. Thus, the low decrease in the photocatalytic activity after three uses makes the nanocomposites suitable for applications in which reusability is an important key factor.

  • improving photocatalytic performance and recyclability by development of er doped and er pr codoped tio2 poly vinylidene Difluoride trifluoroethylene composite membranes
    Journal of Physical Chemistry C, 2014
    Co-Authors: Pedro Manuel Abreu Martins, V Gomez, Ademar Lopes, C J Tavares, Gabriela Botelho, S Irusta, S Lancerosmendez
    Abstract:

    Photocatalysis has become an attractive process to remove contaminants from aquatic environments, with TiO2 being the most widely used photocatalyst. In spite of the advantages of the process, two main problems still have to be overcome: reutilization/recycling of TiO2 nanoparticles, which is a time-consuming and expensive process, and the fast recombination rate of the electron–hole pairs. This work reports on the photocatalytic activity of rare earth metal doped (erbium, Er) and codoped (erbium and praseodymium, Er/Pr) TiO2 nanoparticles immobilized in a poly(vinylidene Difluoride)–trifluoroethylene (PVDF–TrFE) copolymer membrane as a suitable strategy to overcome the aforementioned limitations. It is shown that doped and codoped nanoparticles were successfully immobilized into the PVDF–TrFE membranes, with a controllable degree of porosity. A high surface area (273 m2/g) was attained for these nanoparticles. The low band gap (2.63 eV) of these TiO2-modified nanoparticles, coupled with a highly porous s...

Piercarlo Mustarelli - One of the best experts on this subject based on the ideXlab platform.

Yang She - One of the best experts on this subject based on the ideXlab platform.

  • self suppression of lithium dendrite in all solid state lithium metal batteries with poly vinylidene Difluoride based solid electrolytes
    Advanced Materials, 2019
    Co-Authors: Xue Zhang, Shuo Wang, Chuanjiao Xue, Yang She
    Abstract:

    Polymer-based electrolytes have attracted ever-increasing attention for all-solid-state lithium (Li) metal batteries due to their ionic conductivity, flexibility, and easy assembling into batteries, and are expected to overcome safety issues by replacing flammable liquid electrolytes. However, it is still a critical challenge to effectively block Li dendrite growth and improve the long-term cycling stability of all-solid-state batteries with polymer electrolytes. Here, the interface between novel poly(vinylidene Difluoride) (PVDF)-based solid electrolytes and the Li anode is explored via systematical experiments in combination with first-principles calculations, and it is found that an in situ formed nanoscale interface layer with a stable and uniform mosaic structure can suppress Li dendrite growth. Unlike the typical short-circuiting that often occurs in most studied poly(ethylene oxide) systems, this interface layer in the PVDF-based system causes an open-circuiting feature at high current density and thus avoids the risk of over-current. The effective self-suppression of the Li dendrite observed in the PVDF-LiN(SO2 F)2 (LiFSI) system enables over 2000 h cycling of repeated Li plating-stripping at 0.1 mA cm-2 and excellent cycling performance in an all-solid-state LiCoO2 ||Li cell with almost no capacity fade after 200 cycles at 0.15 mA cm-2 at 25 °C. These findings will promote the development of safe all-solid-state Li metal batteries.

B Scrosati - One of the best experts on this subject based on the ideXlab platform.

  • A Novel Preparation Procedure of Poly(vinylideneDifluoride)-Based Gel Polymer Electrolyte for Application in Lithium-Ion Batteries
    'The Electrochemical Society', 2015
    Co-Authors: C. Fasciani, S. Panero, J. Hassoun, B Scrosati
    Abstract:

    In this work we present a convenient preparation procedure of poly(vinylidene Difluoride) (PVdF)-based gel polymer electrolyte. The novelty of the procedure reported is that the electrolyte is prepared under air as a dry, flexible film and directly gelled during LIB assembly. Therefore, the GPE obtained is easy to handle and suitable for roll-to-roll scaling-up and it can be efficiently used for application in LIB. The morphology and electrochemical interphase properties of the electrolyte have been investigated by scanning electron microscopy and impedance spectroscopy, respectively. Moreover, galvanostatic tests suggested good stability of the lithium electrode/gel electrolyte interface and a high lithium transference number. Finally, cycling tests of full lithium ion cell, employing the GPE, a lithium iron phosphate cathode and a graphite anode confirm the suitability of the GPE for application in stable, low cost and environmentally friendly energy storage systems

  • a safe high rate and high energy polymer lithium ion battery based on gelled membranes prepared by electrospinning
    Energy and Environmental Science, 2011
    Co-Authors: F Croce, Maria Letizia Focarete, Jusef Hassoun, Ida Meschini, B Scrosati
    Abstract:

    In this paper we report on the characteristics of a polymer Li-ion battery based on a unique combination of innovative electrode and electrolyte materials. In particular, the electrolytic separator of this system is based on gelled membranes prepared by the electrospinning technique. Electrospinning of polymer fibers is usually realized by applying a strong electric field to a polymer solution in an appropriate solvent. Typical membranes (mats) consist of nanometre size fibers and have porosities of 56–85%. Here we describe the fabrication, physical chemistry and electrochemical properties of PVdF (poly(vinylidene Difluoride))-based electrospun membranes and their use as gelled electrolyte in Li-ion battery. Moreover, we describe the performances of a battery formed by sandwiching a gelled membrane with a nanoscale engineered Sn–C based anode and a lithium nickel manganese oxide spinel cathode. The battery so obtained has an appealing performance in terms of energy density, power capability, cycle life and safety.

  • a safe high rate and high energy polymer lithium ion battery based on gelled membranes prepared by electrospinning
    Energy and Environmental Science, 2011
    Co-Authors: F Croce, Maria Letizia Focarete, Jusef Hassoun, Ida Meschini, B Scrosati
    Abstract:

    In this paper we report on the characteristics of a polymer Li-ion battery based on a unique combination of innovative electrode and electrolyte materials. In particular, the electrolytic separator of this system is based on gelled membranes prepared by the electrospinning technique. Electrospinning of polymer fibers is usually realized by applying a strong electric field to a polymer solution in an appropriate solvent. Typical membranes (mats) consist of nanometre size fibers and have porosities of 56–85%. Here we describe the fabrication, physical chemistry and electrochemical properties of PVdF (poly(vinylidene Difluoride))-based electrospun membranes and their use as gelled electrolyte in Li-ion battery. Moreover, we describe the performances of a battery formed by sandwiching a gelled membrane with a nanoscale engineered Sn–C based anode and a lithium nickel manganese oxide spinel cathode. The battery so obtained has an appealing performance in terms of energy density, power capability, cycle life and safety.

Pedro Manuel Abreu Martins - One of the best experts on this subject based on the ideXlab platform.

  • reusability of photocatalytic tio2 and zno nanoparticles immobilized in poly vinylidene Difluoride co trifluoroethylene
    Applied Surface Science, 2016
    Co-Authors: Sara Teixeira, Pedro Manuel Abreu Martins, S Lancerosmendez, Klaus Kuhn, Gianaurelio Cuniberti
    Abstract:

    Abstract Pollutants present in water are increasingly becoming an important public health issue. After their transportation across the sewer network they can pass through the wastewater treatment plants (WWTPs) mostly unchanged because WWTPs are not designed to remove pollutants present at trace levels. Conventional treatments are therefore ineffective. Immobilized photocatalytic systems are thus an advantage for the treatment of contaminated water, because they are ecofriendly, cost-effective and allow reusability. This work reports on TiO 2 and ZnO commercial nanoparticles immobilized in poly(vinylidene Difluoride)- co -trifluoroethylene (P(VDF-TrFE)). Nanocomposites of P(VDF-TrFE) with different concentrations of TiO 2 nanoparticles (5, 10, and 15 wt.%) and ZnO nanoparticles (15 wt.%) were produced by solvent casting and tested on the degradation of methylene blue, a model organic dye. Each nanocomposite was tested three times to assess its reusability. It is shown that increasing the photocatalyst concentration results in higher photocatalytic efficiencies; the degradation rates of 15% of TiO 2 and ZnO are similar; and the photoactivity decreases 6%, 16%, 13%, and 11% after three utilizations, for TiO 2 5%, TiO 2 10%, TiO 2 15%, and ZnO 15%, respectively. Thus, the low decrease in the photocatalytic activity after three uses makes the nanocomposites suitable for applications in which reusability is an important key factor.

  • improving photocatalytic performance and recyclability by development of er doped and er pr codoped tio2 poly vinylidene Difluoride trifluoroethylene composite membranes
    Journal of Physical Chemistry C, 2014
    Co-Authors: Pedro Manuel Abreu Martins, V Gomez, Ademar Lopes, C J Tavares, Gabriela Botelho, S Irusta, S Lancerosmendez
    Abstract:

    Photocatalysis has become an attractive process to remove contaminants from aquatic environments, with TiO2 being the most widely used photocatalyst. In spite of the advantages of the process, two main problems still have to be overcome: reutilization/recycling of TiO2 nanoparticles, which is a time-consuming and expensive process, and the fast recombination rate of the electron–hole pairs. This work reports on the photocatalytic activity of rare earth metal doped (erbium, Er) and codoped (erbium and praseodymium, Er/Pr) TiO2 nanoparticles immobilized in a poly(vinylidene Difluoride)–trifluoroethylene (PVDF–TrFE) copolymer membrane as a suitable strategy to overcome the aforementioned limitations. It is shown that doped and codoped nanoparticles were successfully immobilized into the PVDF–TrFE membranes, with a controllable degree of porosity. A high surface area (273 m2/g) was attained for these nanoparticles. The low band gap (2.63 eV) of these TiO2-modified nanoparticles, coupled with a highly porous s...