Helena Braga - Academia.edu (original) (raw)
Papers by Helena Braga
ACS Applied Energy Materials, 2019
An electrochemical cell that powers all-electric road vehicles will likely have an alkali-metal a... more An electrochemical cell that powers all-electric road vehicles will likely have an alkali-metal anode and the ability to operate down to-20C. The traditional all-solid-state batteries can only perform well at temperatures above room temperature. We have shown elsewhere that an alkali-metal negative electrode can be plated dendrite-free from a ferroelectric amorphous-oxide (glass) Li + or Na + electrolyte having a room-temperature Li + or Na + conductivity S.cm-1 similar to that of a liquid ≈ 2.5 10-2 electrolyte. Here, it is demonstrated that the ionic conductivity of the electrolyte is S.cm-1 at-≈ 10-2 20C after optimization and the dielectric constant is at-35C. Moreover, it is shown that ε ′ ≈ 6 × 10 5 the remanent polarization of the ferroelectric-electrolyte (polarization at zero potential) adds to the capacity of the cell. The Electrochemical cycling performances between-35 and 25C of the Li +-glass electrolyte in gold and lithium symmetric cells and in full cells are presented. Furthermore, it is shown that a coin-cell with the ferroelectric Li-glass electrolyte at-35C with output current of 56 A.cm-2 can light a red LED at 1.5 V. Finally, it is concluded that the Li +-glass electrolyte performs very well in symmetric cells and performs reasonably well down to-20C in asymmetric cells that also rely on the performance of the cathode and on the electrolyte/cathode interface.
Phys. Chem. Chem. Phys., 2014
Cu–Li–Mg–H novel hydrides and catalytic processes will open new vistas in the field of storage fo... more Cu–Li–Mg–H novel hydrides and catalytic processes will open new vistas in the field of storage for both hydrogen and batteries.
MRS Proceedings, 2010
Cu-Li-Mg-(H,D) was studied as an example of destabilizer of the Ti-(H,D) system. A Cu-Li-Mg alloy... more Cu-Li-Mg-(H,D) was studied as an example of destabilizer of the Ti-(H,D) system. A Cu-Li-Mg alloy was prepared resulting in the formation of a system with 60.5 at% of CuLi0.08Mg1.92, 23.9 at% of CuMg2 and 15.6 at% of Cu2Mg. Titanium was added to a fraction of this mixture so that 68.2 at% (47.3 wt%) of the final mixture was Ti. The mixture was ground and kept at 200 °C/473 K for 7h under H2 or 9h under D2 at P = 34 bar. Under those conditions, neutron powder diffraction shows the formation of TiD2, as well as of the deuteride of CuLi0.08Mg1.92. Similarly inelastic neutron scattering shows that at 10 K TiH2 is present in the sample, together with the hydride of CuLi0.08Mg1.92. Interestingly, at 10 K TiH2 is very clearly detected and at 300 K TiH2 is still clearly present as indicated by the neutron vibrational spectrum, but CuLi0.08Mg1.92-H is not detected anymore. These results indicate that Ti(H,D)2 is possibly formed by diffusion of hydrogen from the Cu-Li-Mg-(H,D) alloys. This is...
Journal of Physics: Conference Series, 2010
We investigated the ternary Cu-Li-Mg system, in particular the CuLi x Mg 2-x (x = 0.08) for hydro... more We investigated the ternary Cu-Li-Mg system, in particular the CuLi x Mg 2-x (x = 0.08) for hydrogen storage. Instead of crystallizing in an orthorhombic phase, as CuMg 2 , this phase presents a hexagonal structure very similar to that of NiMg 2 and NiMg 2 H 0.3. In this work we will discuss the structure of CuLi x Mg 2-x by the analysis of the neutron scattering data and first principles calculations. The first results for a hydride (deuteride) phase will also mentioned since preliminary studies at LANSCE showed that CuLi x Mg 2-x might absorb approximately 5.3 to 6 wt% of H at an equilibrium pressure of approximately 27 bar at 200 o C. If these results are confirmed in future work, this will mean that, not only CuLi x Mg 2-x absorbs a considerable amount of hydrogen (close to DOE's expectations for hydrogen storage materials), but also will probably release it at a temperature in the range of 50 to 150 o C, where applications are easier to develop. Hence it should be possible to use this alloy with fuel cells or in batteries. Another important observation is that cycling has a strong effect on the structure of the hydride.
Calphad, 2009
Using phase field simulations, it is possible to simulate the dynamics and morphology of immiscib... more Using phase field simulations, it is possible to simulate the dynamics and morphology of immiscible liquids/solids appearing at the miscibility gap of any system. These simulations may also be used to determine the asymptotic compositions of the fluids for a given Gibbs energy. Even more, it is known that different parameters of the excess Gibbs energy of a certain phase may exhibit different asymptotic morphologies, in spite of the similarity of the associated equilibrium curves. This method can be used to choose the best excess Gibbs energy' parameters for the liquid (or solid) phase of a system that will suffer spinodal decomposition. It can also be important (like in the sol-gel process) to choose the best composition, temperature and time to obtain a certain wanted morphology, just by means of the Gibbs energy of the respective phase. In this work, we have performed phase field simulations of the two liquid's separation occurring in the Bi-Zn system, for different temperatures, concentrations and times. We have found a rich diversity of asymptotic morphologies for different points of the Bi-Zn phase diagram. Two different Gibbs energies were used to show how the morphologies will be affected by different parameters of the excess Gibbs energy.
Calphad, 2007
The binary Bi-Sn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersiv... more The binary Bi-Sn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersive solid state Spectrometry), DTA (Differential Thermal Analysis)/DSC (Differential Scanning Calorimetry) and RT-XRD (Room Temperature X-Ray Diffraction) in order to clarify discrepancies concerning the Bi reported solubility in (Sn). It was found that (Sn) dissolves approximately 10 wt% of Bi at the eutectic temperature. The experimental effort for the Bi-Zn system was limited to the investigation of the discrepancies concerning the solubility limit of Zn in (Bi) and the solubility of Bi in (Zn). Results indicate that the solubility of both elements in the respective solid solution is approximately 0.3 wt% at 200 • C. Three different features were studied within the Bi-Sn-Zn system. Although there are enough data to establish the liquid miscibility gap occurring in the phase diagram of binary Bi-Zn, no data could be found for the ternary. Samples belonging to the isopleths with w(Bi) ∼ 10% and w(Sn) ∼ 5%, 13% and 19% were measured by DTA/DSC. The aim was to characterize the miscibility gap in the liquid phase. Samples belonging to the isopleths with w(Sn) ∼ 40%, 58%, 77/81% and w(Zn) ∼ 12% were also measured by DTA/DSC to complement the study of Bi-Sn-Zn. Solubilities in the solid terminal solutions were determined by SEM/EDS. Samples were also analyzed by RT-XRD and HT-XRD (High Temperature X-Ray Diffraction) confirming the DTA/DSC results for solid state phase equilibria.
Calphad, 2007
A thermodynamic assessment of the Bi-Sn-Zn ternary system was carried out using the CALPHAD appro... more A thermodynamic assessment of the Bi-Sn-Zn ternary system was carried out using the CALPHAD approach along with thermodynamic descriptions from new assessments of the Bi-Sn and Bi-Zn systems. Selected experimental data from the literature and our own work were also used. New sets of optimized thermodynamic parameters were obtained that lead to a very good fit between the calculated and experimental data. The Bi-Sn-Zn system is one of the candidates for lead-free solder materials.
Journal of Materials Chemistry A
We present a comprehensive perspective on the fundamental components of a solid-state battery, st... more We present a comprehensive perspective on the fundamental components of a solid-state battery, starting from all-solid-state electrolytes and extending to quantum power harvesting and storage. Firstly, we enquire into the...
Nature Communications, 2021
Physical Review Materials, 2021
Although electrostatic gating with liquid electrolytes has been thoroughly investigated to enhanc... more Although electrostatic gating with liquid electrolytes has been thoroughly investigated to enhance electrical transport in two-dimensional (2D) materials, solid electrolyte alternatives are now actively being researched to overcome the limitations of liquid dielectrics. Here, we report direct growth of few-layer (3−4L) molybdenum disulfide (MoS 2), a prototypical 2D transition metal dichalcogenide (TMD), on lithium-ion solid electrolyte substrate by chemical vapor deposition (CVD), and demonstrate a transfer-free device fabrication method. The growth resulted in 5-10 μm sized triangular MoS 2 single crystals as confirmed by Raman spectroscopy, x-ray photoelectron spectroscopy, and scanning electron microscopy. Field-effect transistors (FETs) fabricated on the as-grown few-layer crystals show near-ideal gating performance with room temperature subthreshold swings around 65 mV/decade while maintaining an ON/OFF ratio around 10 5. Field-effect mobility in the range of 42-49 cm 2 V-1 s-1 and current densities as high as 120 μA/μm with 0.5 μm channel length has been achieved, back-gated by the solid electrolyte. This is the highest reported mobility among comparable FETs on as-grown single/few-layer CVD MoS 2. This growth and transfer-free device fabrication method on solid electrolyte substrates can be applied to other 2D TMDs for studying advanced thin-film transistors and interesting physics, and is amenable to diverse surface science experiments, otherwise difficult to realize with liquid electrolytes.
Polymers, 2022
Solid-state electrolytes are a promising family of materials for the next generation of high-ener... more Solid-state electrolytes are a promising family of materials for the next generation of high-energy rechargeable lithium batteries. Polymer electrolytes (PEs) have been widely investigated due to their main advantages, which include easy processability, high safety, good mechanical flexibility, and low weight. This review presents recent scientific advances in the design of versatile polymer-based electrolytes and composite electrolytes, underlining the current limitations and remaining challenges while highlighting their technical accomplishments. The recent advances in PEs as a promising application in structural batteries are also emphasized.
- Plenary talk - A family of hydrides, including the high capacity MgH 2 and LiH, is reported. Th... more - Plenary talk - A family of hydrides, including the high capacity MgH 2 and LiH, is reported. The disadvantages these hydrides normally display (high absorption/desorption temperatures and poor kinetics) are mitigated by Cu-hydride catalysis. The CuLi 0.08 Mg 1.42 H 4 and CuLi 0.08 Mg 1.92 H 5 hydrides are characterized. The CuLi 0.08 Mg 1.42 H 4 structure in nanotubes is able to hold molecular H 2 , increasing the gravimetric and volumetric capacity of this compound. The catalytic effect these compounds show on hydride formation and decomposition of CuMg 2 and Cu 2 Mg/MgH 2 , Li and LiH, Mg and MgH 2 is analyzed. The Gibbs energy, decomposition temperature, and gravimetric capacity of the reactions occurring within the Cu-Li-Mg-H system are presented. First principles and phonon calculations are compared with experiments, including neutron spectroscopy. It is demonstrated that the most advantageous sample contains CuLi 0.08 Mg 1.92 and (Li)∼Li 2 Mg 3 ; it desorbs/absorbs hydrogen according to the reaction, 2CuLi 0.08 Mg 1.42 H 4 +2Li+4MgH 2 ↔2CuLi 0.08 Mg 1.92 +Li 2 Mg 3 +8H 2 at 114°C (5.0 wt%) - 1 atm, falling within the proton exchange membrane fuel cell applications window
Thermoelectric Generators have a wide range of applications and can be an important way of turnin... more Thermoelectric Generators have a wide range of applications and can be an important way of turning the world into a more sustainable place through the recovery of wasted heat. Carbon-based materials bring a new opportunity in the thermoelectric field due to their abundant source, cheapness, non-toxicity and flexibility. The transport properties of these materials can be improved through chemical, mechanical and thermal treatments. The focus of the present work is to tune the thermoelectric properties of multi-walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GN) by using different functionalizations process such as HNO3, melamine, ball milling and thermal treatments in N2 atmosphere. Morphological, structural and textural analyses are discussed to understand the changes observed in the thermoelectric properties of the functionalized materials.
The European Commission support for the production of this publication under the Grant Agreement ... more The European Commission support for the production of this publication under the Grant Agreement Nº 2019-612675 does not constitute an endorsement of the contents which reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Highlight Lecture *web*Self-charge and self-cycling energy storage devices with the ferroelectric... more Highlight Lecture *web*Self-charge and self-cycling energy storage devices with the ferroelectric 'Braga' glass electrolyte 1 Prof. Joana Oliveira We would like to thank you very much for being the Session Chair of the MSE2020 Session 14:40 F01.3: All solid state batteries which will take place on Tuesday, 22.09.2020 15:40-16:40 (CEST).
Portugal 3.25 p.m. (Lisbon) | 9.25 a.m. (Austin) Short break 3.40 p.m. (Lisbon) | 9.40 a.m. (Aust... more Portugal 3.25 p.m. (Lisbon) | 9.25 a.m. (Austin) Short break 3.40 p.m. (Lisbon) | 9.40 a.m. (Austin) Keynote Speech II | Luis Sentis (UT Austin) "Invention and commercialization of human-centered robots through academic-industry collaborations with NASA" 4.20 p.m. (Lisbon) | 10.20 a.m. (Austin) Moderated discussion with Keynote Speaker Luis Sentis Discussants: Pedro Camanho (FEUP, INEGI and LAETA) and Ricardo Conde (Portugal Space) Moderator: Rui Oliveira, National Co-Director of UT Austin Portugal 4.45 p.m. (Lisbon) | 10.45 a.m. (Austin) Innovation at the Intersection of Academia and Industry: UT Austin Portugal's elite of industry-driven research projects 4.50 p.m. (Lisbon) | 10.50 a.m. (Austin) Closing Remarks Message from Manuel Heitor, Minister of Science, Technology and Higher Education 2.20 p.m. (Lisbon) | 8.20 a.m. (Austin) Keynote Speech I | Maria Helena Braga (FEUP) "The future of batteries as we know them today: possible entanglements leading to a transformation"
ACS Applied Energy Materials, 2019
An electrochemical cell that powers all-electric road vehicles will likely have an alkali-metal a... more An electrochemical cell that powers all-electric road vehicles will likely have an alkali-metal anode and the ability to operate down to-20C. The traditional all-solid-state batteries can only perform well at temperatures above room temperature. We have shown elsewhere that an alkali-metal negative electrode can be plated dendrite-free from a ferroelectric amorphous-oxide (glass) Li + or Na + electrolyte having a room-temperature Li + or Na + conductivity S.cm-1 similar to that of a liquid ≈ 2.5 10-2 electrolyte. Here, it is demonstrated that the ionic conductivity of the electrolyte is S.cm-1 at-≈ 10-2 20C after optimization and the dielectric constant is at-35C. Moreover, it is shown that ε ′ ≈ 6 × 10 5 the remanent polarization of the ferroelectric-electrolyte (polarization at zero potential) adds to the capacity of the cell. The Electrochemical cycling performances between-35 and 25C of the Li +-glass electrolyte in gold and lithium symmetric cells and in full cells are presented. Furthermore, it is shown that a coin-cell with the ferroelectric Li-glass electrolyte at-35C with output current of 56 A.cm-2 can light a red LED at 1.5 V. Finally, it is concluded that the Li +-glass electrolyte performs very well in symmetric cells and performs reasonably well down to-20C in asymmetric cells that also rely on the performance of the cathode and on the electrolyte/cathode interface.
Phys. Chem. Chem. Phys., 2014
Cu–Li–Mg–H novel hydrides and catalytic processes will open new vistas in the field of storage fo... more Cu–Li–Mg–H novel hydrides and catalytic processes will open new vistas in the field of storage for both hydrogen and batteries.
MRS Proceedings, 2010
Cu-Li-Mg-(H,D) was studied as an example of destabilizer of the Ti-(H,D) system. A Cu-Li-Mg alloy... more Cu-Li-Mg-(H,D) was studied as an example of destabilizer of the Ti-(H,D) system. A Cu-Li-Mg alloy was prepared resulting in the formation of a system with 60.5 at% of CuLi0.08Mg1.92, 23.9 at% of CuMg2 and 15.6 at% of Cu2Mg. Titanium was added to a fraction of this mixture so that 68.2 at% (47.3 wt%) of the final mixture was Ti. The mixture was ground and kept at 200 °C/473 K for 7h under H2 or 9h under D2 at P = 34 bar. Under those conditions, neutron powder diffraction shows the formation of TiD2, as well as of the deuteride of CuLi0.08Mg1.92. Similarly inelastic neutron scattering shows that at 10 K TiH2 is present in the sample, together with the hydride of CuLi0.08Mg1.92. Interestingly, at 10 K TiH2 is very clearly detected and at 300 K TiH2 is still clearly present as indicated by the neutron vibrational spectrum, but CuLi0.08Mg1.92-H is not detected anymore. These results indicate that Ti(H,D)2 is possibly formed by diffusion of hydrogen from the Cu-Li-Mg-(H,D) alloys. This is...
Journal of Physics: Conference Series, 2010
We investigated the ternary Cu-Li-Mg system, in particular the CuLi x Mg 2-x (x = 0.08) for hydro... more We investigated the ternary Cu-Li-Mg system, in particular the CuLi x Mg 2-x (x = 0.08) for hydrogen storage. Instead of crystallizing in an orthorhombic phase, as CuMg 2 , this phase presents a hexagonal structure very similar to that of NiMg 2 and NiMg 2 H 0.3. In this work we will discuss the structure of CuLi x Mg 2-x by the analysis of the neutron scattering data and first principles calculations. The first results for a hydride (deuteride) phase will also mentioned since preliminary studies at LANSCE showed that CuLi x Mg 2-x might absorb approximately 5.3 to 6 wt% of H at an equilibrium pressure of approximately 27 bar at 200 o C. If these results are confirmed in future work, this will mean that, not only CuLi x Mg 2-x absorbs a considerable amount of hydrogen (close to DOE's expectations for hydrogen storage materials), but also will probably release it at a temperature in the range of 50 to 150 o C, where applications are easier to develop. Hence it should be possible to use this alloy with fuel cells or in batteries. Another important observation is that cycling has a strong effect on the structure of the hydride.
Calphad, 2009
Using phase field simulations, it is possible to simulate the dynamics and morphology of immiscib... more Using phase field simulations, it is possible to simulate the dynamics and morphology of immiscible liquids/solids appearing at the miscibility gap of any system. These simulations may also be used to determine the asymptotic compositions of the fluids for a given Gibbs energy. Even more, it is known that different parameters of the excess Gibbs energy of a certain phase may exhibit different asymptotic morphologies, in spite of the similarity of the associated equilibrium curves. This method can be used to choose the best excess Gibbs energy' parameters for the liquid (or solid) phase of a system that will suffer spinodal decomposition. It can also be important (like in the sol-gel process) to choose the best composition, temperature and time to obtain a certain wanted morphology, just by means of the Gibbs energy of the respective phase. In this work, we have performed phase field simulations of the two liquid's separation occurring in the Bi-Zn system, for different temperatures, concentrations and times. We have found a rich diversity of asymptotic morphologies for different points of the Bi-Zn phase diagram. Two different Gibbs energies were used to show how the morphologies will be affected by different parameters of the excess Gibbs energy.
Calphad, 2007
The binary Bi-Sn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersiv... more The binary Bi-Sn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersive solid state Spectrometry), DTA (Differential Thermal Analysis)/DSC (Differential Scanning Calorimetry) and RT-XRD (Room Temperature X-Ray Diffraction) in order to clarify discrepancies concerning the Bi reported solubility in (Sn). It was found that (Sn) dissolves approximately 10 wt% of Bi at the eutectic temperature. The experimental effort for the Bi-Zn system was limited to the investigation of the discrepancies concerning the solubility limit of Zn in (Bi) and the solubility of Bi in (Zn). Results indicate that the solubility of both elements in the respective solid solution is approximately 0.3 wt% at 200 • C. Three different features were studied within the Bi-Sn-Zn system. Although there are enough data to establish the liquid miscibility gap occurring in the phase diagram of binary Bi-Zn, no data could be found for the ternary. Samples belonging to the isopleths with w(Bi) ∼ 10% and w(Sn) ∼ 5%, 13% and 19% were measured by DTA/DSC. The aim was to characterize the miscibility gap in the liquid phase. Samples belonging to the isopleths with w(Sn) ∼ 40%, 58%, 77/81% and w(Zn) ∼ 12% were also measured by DTA/DSC to complement the study of Bi-Sn-Zn. Solubilities in the solid terminal solutions were determined by SEM/EDS. Samples were also analyzed by RT-XRD and HT-XRD (High Temperature X-Ray Diffraction) confirming the DTA/DSC results for solid state phase equilibria.
Calphad, 2007
A thermodynamic assessment of the Bi-Sn-Zn ternary system was carried out using the CALPHAD appro... more A thermodynamic assessment of the Bi-Sn-Zn ternary system was carried out using the CALPHAD approach along with thermodynamic descriptions from new assessments of the Bi-Sn and Bi-Zn systems. Selected experimental data from the literature and our own work were also used. New sets of optimized thermodynamic parameters were obtained that lead to a very good fit between the calculated and experimental data. The Bi-Sn-Zn system is one of the candidates for lead-free solder materials.
Journal of Materials Chemistry A
We present a comprehensive perspective on the fundamental components of a solid-state battery, st... more We present a comprehensive perspective on the fundamental components of a solid-state battery, starting from all-solid-state electrolytes and extending to quantum power harvesting and storage. Firstly, we enquire into the...
Nature Communications, 2021
Physical Review Materials, 2021
Although electrostatic gating with liquid electrolytes has been thoroughly investigated to enhanc... more Although electrostatic gating with liquid electrolytes has been thoroughly investigated to enhance electrical transport in two-dimensional (2D) materials, solid electrolyte alternatives are now actively being researched to overcome the limitations of liquid dielectrics. Here, we report direct growth of few-layer (3−4L) molybdenum disulfide (MoS 2), a prototypical 2D transition metal dichalcogenide (TMD), on lithium-ion solid electrolyte substrate by chemical vapor deposition (CVD), and demonstrate a transfer-free device fabrication method. The growth resulted in 5-10 μm sized triangular MoS 2 single crystals as confirmed by Raman spectroscopy, x-ray photoelectron spectroscopy, and scanning electron microscopy. Field-effect transistors (FETs) fabricated on the as-grown few-layer crystals show near-ideal gating performance with room temperature subthreshold swings around 65 mV/decade while maintaining an ON/OFF ratio around 10 5. Field-effect mobility in the range of 42-49 cm 2 V-1 s-1 and current densities as high as 120 μA/μm with 0.5 μm channel length has been achieved, back-gated by the solid electrolyte. This is the highest reported mobility among comparable FETs on as-grown single/few-layer CVD MoS 2. This growth and transfer-free device fabrication method on solid electrolyte substrates can be applied to other 2D TMDs for studying advanced thin-film transistors and interesting physics, and is amenable to diverse surface science experiments, otherwise difficult to realize with liquid electrolytes.
Polymers, 2022
Solid-state electrolytes are a promising family of materials for the next generation of high-ener... more Solid-state electrolytes are a promising family of materials for the next generation of high-energy rechargeable lithium batteries. Polymer electrolytes (PEs) have been widely investigated due to their main advantages, which include easy processability, high safety, good mechanical flexibility, and low weight. This review presents recent scientific advances in the design of versatile polymer-based electrolytes and composite electrolytes, underlining the current limitations and remaining challenges while highlighting their technical accomplishments. The recent advances in PEs as a promising application in structural batteries are also emphasized.
- Plenary talk - A family of hydrides, including the high capacity MgH 2 and LiH, is reported. Th... more - Plenary talk - A family of hydrides, including the high capacity MgH 2 and LiH, is reported. The disadvantages these hydrides normally display (high absorption/desorption temperatures and poor kinetics) are mitigated by Cu-hydride catalysis. The CuLi 0.08 Mg 1.42 H 4 and CuLi 0.08 Mg 1.92 H 5 hydrides are characterized. The CuLi 0.08 Mg 1.42 H 4 structure in nanotubes is able to hold molecular H 2 , increasing the gravimetric and volumetric capacity of this compound. The catalytic effect these compounds show on hydride formation and decomposition of CuMg 2 and Cu 2 Mg/MgH 2 , Li and LiH, Mg and MgH 2 is analyzed. The Gibbs energy, decomposition temperature, and gravimetric capacity of the reactions occurring within the Cu-Li-Mg-H system are presented. First principles and phonon calculations are compared with experiments, including neutron spectroscopy. It is demonstrated that the most advantageous sample contains CuLi 0.08 Mg 1.92 and (Li)∼Li 2 Mg 3 ; it desorbs/absorbs hydrogen according to the reaction, 2CuLi 0.08 Mg 1.42 H 4 +2Li+4MgH 2 ↔2CuLi 0.08 Mg 1.92 +Li 2 Mg 3 +8H 2 at 114°C (5.0 wt%) - 1 atm, falling within the proton exchange membrane fuel cell applications window
Thermoelectric Generators have a wide range of applications and can be an important way of turnin... more Thermoelectric Generators have a wide range of applications and can be an important way of turning the world into a more sustainable place through the recovery of wasted heat. Carbon-based materials bring a new opportunity in the thermoelectric field due to their abundant source, cheapness, non-toxicity and flexibility. The transport properties of these materials can be improved through chemical, mechanical and thermal treatments. The focus of the present work is to tune the thermoelectric properties of multi-walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GN) by using different functionalizations process such as HNO3, melamine, ball milling and thermal treatments in N2 atmosphere. Morphological, structural and textural analyses are discussed to understand the changes observed in the thermoelectric properties of the functionalized materials.
The European Commission support for the production of this publication under the Grant Agreement ... more The European Commission support for the production of this publication under the Grant Agreement Nº 2019-612675 does not constitute an endorsement of the contents which reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Highlight Lecture *web*Self-charge and self-cycling energy storage devices with the ferroelectric... more Highlight Lecture *web*Self-charge and self-cycling energy storage devices with the ferroelectric 'Braga' glass electrolyte 1 Prof. Joana Oliveira We would like to thank you very much for being the Session Chair of the MSE2020 Session 14:40 F01.3: All solid state batteries which will take place on Tuesday, 22.09.2020 15:40-16:40 (CEST).
Portugal 3.25 p.m. (Lisbon) | 9.25 a.m. (Austin) Short break 3.40 p.m. (Lisbon) | 9.40 a.m. (Aust... more Portugal 3.25 p.m. (Lisbon) | 9.25 a.m. (Austin) Short break 3.40 p.m. (Lisbon) | 9.40 a.m. (Austin) Keynote Speech II | Luis Sentis (UT Austin) "Invention and commercialization of human-centered robots through academic-industry collaborations with NASA" 4.20 p.m. (Lisbon) | 10.20 a.m. (Austin) Moderated discussion with Keynote Speaker Luis Sentis Discussants: Pedro Camanho (FEUP, INEGI and LAETA) and Ricardo Conde (Portugal Space) Moderator: Rui Oliveira, National Co-Director of UT Austin Portugal 4.45 p.m. (Lisbon) | 10.45 a.m. (Austin) Innovation at the Intersection of Academia and Industry: UT Austin Portugal's elite of industry-driven research projects 4.50 p.m. (Lisbon) | 10.50 a.m. (Austin) Closing Remarks Message from Manuel Heitor, Minister of Science, Technology and Higher Education 2.20 p.m. (Lisbon) | 8.20 a.m. (Austin) Keynote Speech I | Maria Helena Braga (FEUP) "The future of batteries as we know them today: possible entanglements leading to a transformation"