Suchergebnisse

Lightweight multifunctional materials represent an increasing field in materials science and engineering based on their technological applications in a wide variety of areas ranging from sensors and actuators, materials for structural and environmental applications, energy generation and storage, or biomedicine, among others. This chapter presents an overview on the main types, preparation techniques and applications of the most relevant lightweight multifunctional materials, as well as on relevant materials to be applied and/or implemented in lightweight structures. ; FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/CTM/50025/2019, UID/FIS/04650/2019; and supported by FEDER funds through the COMPETE 2020 Programme under the project number PTDC/FIS-MAC/28157/2017 and POCI-01-0145- FEDER-007688. The authors also thank the FCT for financial support under grants SFRH/BPD/112547/2015 (C.M.C.) and SFRH/BPD/110914/2015 (P. C.). Financial support from the Basque Government under the ELKARTEK, HAZITEK and PIBA ...

The growing demand for weight-saving engineering applications has led to the progress of lightweight composites with functional properties for an increasing number of applications. Lightweight materials with functional properties can be developed using a wide range of host matrices and reinforcement material. These large variety of possible combinations allow the development of new functional materials, structures and devices and that represent the present and the future of different engineering areas. Their novel properties combined with advanced manufacturing processes strongly increases the use of these materials in applications. This chapter presents some relevant challenges and an outlook on the future of this field. ; The authors thank the FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2019, UID/EEA/04436/2013 and UID/QUI/0686/2016; projects PTDC/EEI-SII/5582/2014 and PTDC/FIS-MAC/28157/2017 and grants s SFRH/BPD/110914/2015 (P.C.) and SFRH/BPD/112547/2015 (C.M.C.) Funding from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06) programs, respectively, is also ...

Sensing smart labels are an essential component of the Internet of Things (IoT) to provide identification and data. However, the widespread use of these labels into functional devices requires easy integration and power supply. Herein, a smart label is presented with integrated humidity sensor and printed battery. The smart label is composed by detection, communication, control, and energy subsystems. It is based on a screen printed RLC circuit and a printed humidity sensor with electrical linear response. The printed battery based on lithium iron phosphate as an active cathode material is fabricated with six single cells connected in series, leading to approximate to 100 mAh g(-1). The printed humidity sensor has a linear response with a sensitivity of 0.004/% relative humidity (RH). Thus, it demonstrates the development of fully printed smart labels, improving integration into a variety of applications. ; The authors thank the Fundacao para a Ciencia e Tecnologia (FCT) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2020, UID/EEA/04436/2020, and UID/QUI/0686/2020 and project no. PTDC/FIS-MAC/28157/2017. The authors also thank the FCT for financial support under grants SFRH/BD/131729/2017 (N.P.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Basque Government under the ELKARTEK, HAZITEK, and PIBA (PIBA-2018-06) programs was also ...

As a result of the Internet of Things (IoT) and Industry 4.0 paradigms, based on increasing interconnectivity, the development of advanced high-performance materials for sensor and actuator applications are increasingly required. In particular, piezoelectric composites are of large scientific and technological interest from fundamental and applied point of views. Piezoelectric composites are applied in a wide range of applications as they combine the excellent properties of polymers and ceramics. The definition and properties of piezoelectric materials and composites are presented as well as the recent applications in areas such as electronics, energy harvesting, environmental sensors and biomedical applications. The outlook and future trends for piezoelectric composites are also provided. ; FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2020, UID/EEA/04436/2020 and UID/QUI/0686/2020; and project no. PTDC/FISMAC/28157/2017, PTDC/BTM-MAT/28237/2017 and PTDC/EMDEMD/28159/2017. The authors also thank the FCT for financial support under grants SFRH/BD/145455/2019 (E.C.), SFRH/BD/145345/2019 (L.F.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06).

Efficient energy storage systems are increasingly needed due to advances in portable electronics and transport vehicles, lithium-ion batteries standing out among the most suitable energy storage systems for a large variety of applications. In lithium-ion batteries, the porous separator membrane plays a relevant role as it is placed between the electrodes and serves as a charge transfer medium and affects the cycle behavior. Typically, porous separators membranes are comprised of a synthetic polymeric matrix embedded in the electrolyte solution. The present chapter focus on recent advances in synthetic polymers for porous separation membranes, as well as on the techniques for membrane preparation and physicochemical characterization. The main challenges to improve synthetic polymer performance for battery separator membrane applications are also discussed. ; Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2019, UID/QUI/50006/2019, UID/QUI/0686/2016 and UID/EMS/00151/2019. The authors thank FEDER funds through the COMPETE 2020 Programme and National Funds through FCT under the project PTDC/FIS-MAC/28157/2017, Grants 38 SFRH/BPD/117838/2016 (JNP). and SFRH/BPD/112547/2015 (C.M.C). Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R (AEI/FEDER, UE) (including the FEDER financial support) and from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA ...

This work reports the development of renewable cellulose nanocrystal (CNC) and ionic liquid (IL) hybrid materials for bending actuator applications. For this purpose, cellulose nanocrystals with different surface charges (neutral, positive and negative) were prepared and increasing amounts of the IL 2-hydroxy-ethyl-trimethylammonium dihydrogen phosphate ([Ch][DHP]) (10 and 25 wt%) were incorporated into the CNC hosting matrix. The morphology of the samples was evaluated, proving that both surface charge and IL incorporation do not affect the characteristic layered structure of the CNC. Atomic force microscopy results reveal a sea-island morphology in the hybrid films, where CNC bundles are surrounded by [Ch][DHP]-rich regions. An increase in the electrical conductivity is observed upon IL incorporation into the CNC matrix, regardless of the CNC surface charge. The highest electrical conductivity values are observed for IL/CNC (+) 25 wt% with an electrical conductivity of 3.18 x 10(-5) +/- 2.75 x 10(-7) S cm(-1) and IL/CNC (-) 10 wt% (1.26 x 10(-5) +/- 5.92 x 10(-6) S cm(-1)). The highest bending displacement of 2.1 mm for an applied voltage of 4.0 Vpp at a frequency of 100 mHz was obtained for the IL/CNC (+) 25 wt% composite, demonstrating the suitability of cellulose to develop soft actuators. ; The authors thank FCT - Fundacao para a Ciencia e Tecnologia - for financial support under the framework of the Strategic Funding UID/FIS/04650/2019 and UID/QUI/50006/2019 and projects PTDC/BTM-MAT/28237/2017, PTDC/EMD-EMD/28159/2017 and PTDC/FIS-MAC/28157/2017. D. M. C., C. M. C. and L. C. F. also acknowledge FCT for the grants SFRH/BPD/121526/2016, SFRH/BPD/112547/2015 and SFRH/BD/145345/2019, respectively. The authors acknowledge funding by the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry and Education Department under the ELKARTEK and PIBA (PIBA-2018-06) programs, ...

Lithium-ion batteries (LIBs) are currently the fastest growing segment of the global battery market, and the preferred electrochemical energy storage system for portable applications. Magnetism is one of the forces that can be applied improve performance, since the application of magnetic fields influences electrochemical reactions through variation of electrolyte properties, mass transportation, electrode kinetics, and deposits morphology. This review provides a description of the magnetic forces present in electrochemical reactions and focuses on how those forces may be taken advantage of to influence the LIBs components (electrolyte, electrodes, and active materials), improving battery performance. The different ways that magnetic forces can interact with LIBs components are discussed, as well as their influence on the electrochemical behavior. The suitable control of these forces and interactions can lead to higher performance LIBs structures and to the development of innovative concepts. ; Work supported by the Portuguese Foundation for Science and Technology (FCT): projects UID/FIS/04650/2020, UID/CTM/50025/2020, UID/QUI/50006/2020, PTDC/FIS-MAC/28157/2017, Grant SFRH/BPD/112547/2015 (C.M.C.), and Investigator FCT Contract CEECIND/00833/2017 (R.G.) and 2020.04028.CEECIND (C.M.C.), as well POCH and European Union. Financial support from the Basque Government Industry and Education Departments under the ELKARTEK and PIBA (PIBA-2018-06) programs is also acknowledged.

The battery separator is an essential component of batteries and affects their cycling performance. In this work, the effect of different 3D geometries of the battery separator on battery performance was studied keeping the same volume. It was observed that the different geometries affect the cycling performance, the best geometry being the perforated one that cycled up to 90 C. The cycling performance is affected by parameters such as the separator thickness and the electrolyte volume. Through the control of the battery separator geometry it is possible to obtain high performance lithium-ion batteries. ; Portuguese Foundation for Science and Technology (FCT): UID/FIS/04650/2019, PTDC/CTMENE/5387/2014, UID/CTM/50025/2013, PTDC/FIS-MAC/28157/2017, grant SFRH/BPD/112547/2015 (C.M.C.) and contract CEECIND/00833/2017 (R.G.), including FEDER funds through the COMPETE 2020 Programme and National Funds through FCT. Financial support from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs is also acknowledged. F. Miranda was also supported by Portuguese funds through the CIDMA - Center for Research and Development in Mathematics and Applications, and the Portuguese Foundation for Science and Technology ("FCT - Fundação para a Ciência e a Tecnologia"), within project ...

A 3D cone separator geometry for lithium-ion batteries has been optimized taking into account the increase of radius size of one side. Theoretical simulations have been carried out for evaluating the influence of radius size in the cone structure at different discharge rates (1 C and 60 C) in which it was also determined the produced ohmic heat. The value of the discharge capacity in the cone structure depends on the increases of the radius, which is correlated with the electrolyte volume and interface between free electrolyte/cathode. The optimum balance of these parameters is essential for obtaining higher battery performance through this geometry that can be used in the next generation of lithium-ion batteries ; Portuguese Foundation for Science and Technology (FCT): UID/FIS/04650/2019, PTDC/CTMENE/5387/2014, UID/CTM/50025/2013, PTDC/FIS-MAC/28157/2017, grant SFRH/BPD/112547/2015 (C.M.C.) and contract CEECIND/00833/2017 (R.G.), including FEDER funds through the COMPETE 2020 Programme and National Funds through FCT. Financial support from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs is also acknowledged. F. Miranda was also supported by Portuguese funds through the CIDMA - Center for Research and Development in Mathematics and Applications, and the Portuguese Foundation for Science and Technology ("FCT - Fundação para a Ciência e a Tecnologia"), within project ...

Lithium-ion batteries, LIBs are ubiquitous through mobile phones, tablets, laptop computers and many other consumer electronic devices. Their increasing demand, mainly driven by the implementation of the electric vehicles, brings several environmental issues related to the mining, extraction and purification of scarce materials such as cobalt, nickel and lithium. This work provides an overview on the relevance of recycling LIBs and their environmental impact. It also analyses the components of LIBs and evaluates their value in the world market. Although there is a strong focus on lithium, other critical metals, such as cobalt and nickel, are also addressed. Different recycling methods for the different battery components are reported together with the main achievements. The advantages and disadvantages of the different used methods are discussed, and their environmental issues are considered. Finally, the main environmental issues associated with the production, use and end of life of LIBs for electric vehicles are described. ; FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2020, UID/EEA/04436/2020 and UID/QUI/0686/2020; and project PTDC/FIS-MAC/28157/2017. The authors also thank the FCT for financial support under grants SFRH/BD/140842/2018 (J.C.B.) and SFRH/BPD/112547/2015 (C.M.C.) and Investigator FCT Contract CEECIND/00833/ 2017 (R.G.) as well POCH and European Union. Financial support from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06) programs, respectively, are also ...

Sustainable materials are increasingly needed in lithium ion batteries in order to reduce their environmental impact and improve their recyclability. This work reports on the production of separators using poly (L-lactic acid) (PLLA) for lithium ion battery applications. PLLA separators were obtained by solvent casting technique, by varying polymer concentration in solution between 8 wt.% and 12 wt.% in order to evaluate their morphology, thermal, electrical and electrochemical properties. It is verified that morphology and porosity can be tuned by varying polymer concentration and that the separators are thermally stable up to 250 ºC. The best ionic conductivity of 1.6 mS/cm was obtained for the PLLA separator prepared from 10 wt.% polymer concentration in solution, due to the synergistic effect of the morphology and electrolyte uptake. For this membrane, a high discharge capacity value of 93 mAh.g-1 was obtained at the rate of 1C. In this work, it is demonstrated that PLLA is a good candidate for the development of separator membranes, in order to produce greener and environmentally friendly batteries in a circular economy context. ; Work supported by the Portuguese Foundation for Science and Technology (FCT) undes strategic funding UID/FIS/04650/2020 and UID/QUI/0686/2020, project PTDC/FISMAC/28157/2017, and Grants SFRH/BD/140842/2018 (J.C.B.), SFRH/BPD/121526/2016 (D.M.C), CEECIND/00833/2017 (R.G.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs is also acknowledged. Technical and human support provided by SGIker (UPV/EHU, MICINN, GV/EJ, EGEF and ESF) is gratefully ...

Electrospun poly(vinylidene fluoride) (PVDF) fiber membranes doped with different ionic liquids (ILs) and sharing the same anion were produced and their potential as separator membranes for battery applications was evaluated. Different types of ILs containing the same anion, bis(trifluoromethylsulfonyl)im ide [TFSI] , were used with IL concentrations ranging between 0 and 15 wt% The morphology, microstructure, thermal and electrical properties (ionic conductivity and electrochemical window) of the membranes were evaluated. The presence of ILs in the PVDF polymer matrix influences the fiber diameter and the content of the polar 13 phase within the polymer, as well as the degree of crystallinity. The thermal stability of the membranes decreases with the incorporation of IL. Impedance spectroscopy tests show a maximum ionic conductivity of 2.8 mS.cm(-1) for 15% of 1-ethyl-3-methylimidazolium bis(tri fluoromethylsulfonyl)imide ([Emim][TFSI]) at room temperature. The electrochemical stability of the samples ranges from 0.0 to 6.0 V. When evaluated as battery separator membranes in C-LiFePO4 halfcells, a maximum discharge capacity of 119 mAh.g(-1) at C-rate was obtained for the PVDF membrane with 15% [Emim][TFSI], with a coulombic efficiency close to 100%. The results demonstrate that the produced electrospun membranes are suitable for applications as separators for lithium ion batteries (LIBs). ; Work supported by the Portuguese Foundation for Science and Technology (FCT): projects UID/FIS/04650/2019, UID/QUI/0686/2019, UID/CTM/50025/2019, UID/QUI/50006/2019, PTDC/FIS-MAC/28157/2017, and Grants SFRH/BD/140842/2018 (J.C.B.), SFRH/BPD/121526/2016 (D.M.C), CEECIND/00833/2017 (R.G.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-1060 99RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry and Education Departments under the ELKARTEK and HAZITEK programs is also ...

Metronidazole (MNZ) is a recalcitrant antibiotic with toxic and carcinogenic effects in aquatic environments. In this work, Fe-5(FO4)(4)(OH)(3)center dot 2H(2)O (giniite) particles were synthesised with three different alkaline cations (Li+, Na+ and K+) and used as Fenton catalysts for MNZ removal. It is shown that the addition of different cations during the hydrothermal synthesis process promote different morphologies from asterisk-like to flower-like and branches-like, maintaining the crystalline structure of pure giniite. The photo-Fenton activity of these particles was then evaluated through the degradation of MNZ under sunlight radiation for 9 h. The results indicate that the alkaline cation has a predominant role in the photo-Fenton efficiency, as demonstrated by the superior degradation efficiencies of Na@giniite particles (91.2% and 72.5% with giniite concentration of 0.2 g L-1 and 0.07 g L-1, respectively), related with its high surface area (10.7 m(2) g(-1)). Thus, it is demonstrated the suitability of Na@giniite particles as Fenton catalyst for MNZ removal from water. (C) 2020 Elsevier Ltd. All rights reserved. ; This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2020 and PEST-C/QUI/UIO686/2014 and under projects PTDC/BTM-MAT/28237/2017 and PTDC/FIS-MAC/28157/2017. We also thank the financial support from e FCT for grants SFRH/BD/122373/2016 (HS), SFRH/BPD/112547/2015 (CMC), IF/01516/2013 (SF), CTTI-70/19-CF(1) (P.M), and CEECIND/00833/2017 (RG). The authors thank funding by the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry and Education Department under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06) programs, ...

LiMn2O4 and LiMn1.5M0.5O4 (M: Ni, Cu, Co) doped particles have been synthetized by sol-gel. Particles between 50 and 200 nm were obtained with the cubic spinel structure of the LiMn2O4. Ni doping shows a more efficient substitution in the octahedral 16d site, replacing the Mn3+ thorn ion, improving the important drawback of poor cycling behavior of LiMn2O4. The average pore size decrease with the addition of the doped elements in the LiMn2O4 structure from 2.9 to 2.6 nm. Thermal analysis shows that the doped particles present higher thermal stability that the undoped ones. Electrochemical behavior of the cathodes prepared with each of the active materials show that the doping influenced the electrochemical performance of the active material. Thus, a specific capacity of 33, 74, 44 and 53 mAh g(-1) (at C) and 74, 89, 59 and 69 mAh g(-1) (at C/10) were obtained for LiMn2O4, LiMn1.5Ni0.5O4, LiMn1.5Cu0.5O4 and LiMn1.5Co0.5O4 cathodes, respectively. All cathodes present good electrochemical stability with low capacity fade of 0.5 and 3.1% for LiMn1.5Ni0.5O4 and LiMn1.5Cu0.5O4, respectively, after 50 cycles. These results show an improvement of electrochemical performance for LiMn2O4 doped with Ni, Cu and Co, demonstrating their suitability for lithium-ion battery systems. ; Work supported by the Portuguese Foundation for Science and Technology (FCT) funds strategic funding UID/FIS/04650/2020 and UID/QUI/0686/2020, project PTDC/FIS-MAC/28157/2017, and Grants CEECIND/00833/2017 (R.G.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs is also acknowledged. Technical and human support provided by SGIker (UPV/EHU, MICINN, GV/EJ, EGEF and ESF) is gratefully ...

Poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene), P(VDF-TrFE-CFE), samples were prepared by solvent casting by varying polymer concentration and solvent evaporation temperature. Different sample morphologies were obtained depending on the processing conditions, as well as different physical-chemical properties such as degree of crystallinity, mechanical and dielectric properties. On the other hand, the electroactive β-phase content and the degradation temperature of the P(VDF-TrFE-CFE) samples are independent of the processing conditions. At 1 kHz, the highest dielectric constant, ε' = 40, was obtained for the samples prepared with 15 wt% polymer concentration in solutions and processing conditions based on solvent evaporation and polymer melting at 210 °C. Taking into account the high dielectric response, pressure and bending capacitive sensors were developed with excellent response and high sensibility (0.03 kPa−1). The developed materials were evaluated for bending and force detection applications. Thus, it is concluded that the developed P(VDF-TrFE-CFE) films are suitable for a new generation of multifunctional materials for capacitive sensing applications, including both force and deformation sensors and touchpads. ; FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2020, and UID/EEA/04436/2020; and project PTDC/FIS-MAC/28157/2017. The author also thanks the FCT for financial support under grants SFRH/BD/131729/2017 (N.P.), SFRH/BD/110622/2015 (S. G.), SFRH/BD/140842/2018 (J.C.B.), CEECIND/00833/2017 (R.G.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06) programs, respectively, are ...