Prof. Martin Dornheim | University of Nottingham (original) (raw)

Papers by Prof. Martin Dornheim

Research paper thumbnail of Optimization and comprehensive characterization of a faithful tissue culture model of the benign and malignant human prostate

Laboratory Investigation, 2013

Few preclinical models accurately depict normal human prostate tissue or primary prostate cancer ... more Few preclinical models accurately depict normal human prostate tissue or primary prostate cancer (PCa). In vitro systems typically lack complex cellular interactions among structured prostatic epithelia and a stromal microenvironment, and genetic and molecular fidelity are concerns in both in vitro and in vivo models. 'Tissue slice cultures' (TSCs) provide realistic preclinical models of diverse tissues and organs, but have not been fully developed or widely utilized for prostate studies. Problems encountered include degeneration of differentiated secretory cells, basal cell hyperplasia, and poor survival of PCa. Here, we optimized, characterized, and applied a TSC model of primary human PCa and benign prostate tissue that overcomes many deficiencies of current in vitro models. Tissue cores from fresh prostatectomy specimens were precision-cut at 300 mm and incubated in a rotary culture apparatus. The ability of varied culture conditions to faithfully maintain benign and cancer cell and tissue structure and function over time was evaluated by immunohistological and biochemical assays. After optimization of the culture system, molecular and cellular responses to androgen ablation and to piperlongumine (PL), purported to specifically reduce androgen signaling in PCa, were investigated. Optimized culture conditions successfully maintained the structural and functional fidelity of both benign and PCa TSCs for 5 days. TSCs exhibited androgen dependence, appropriately undergoing ductal degeneration, reduced proliferation, and decreased prostate-specific antigen expression upon androgen ablation. Further, TSCs revealed cancer-specific reduction of androgen receptor and increased apoptosis upon treatment with PL, validating data from cell lines. We demonstrate a TSC model that authentically recapitulates the structural, cellular, and genetic characteristics of the benign and malignant human prostate, androgen dependence of the native tissue, and cancer-specific response to a potentially new therapeutic for PCa. The work described herein provides a basis for advancing the experimental utility of the TSC model.

Research paper thumbnail of Modellgestützte verfahrenstechnische Berechnung eines Metallhydridspeichers auf Natriumalanatbasis im Technikumsmaßstab

Chemie Ingenieur Technik, May 1, 2009

Im Rahmen des EU-Projekts STORHY ist der Prototyp eines Metallhydridspeichers auf Natriumalanatba... more Im Rahmen des EU-Projekts STORHY ist der Prototyp eines Metallhydridspeichers auf Natriumalanatbasis für automobile Anwendungen entwickelt worden. Besonderes Merkmal ist die Größe im Vergleich zu bisher vorhandenen Laborreaktoren. Mit Hilfe einer modellgestützten Simulation wird sein Beladungsverhalten für verschiedene Betriebsbedingungen berechnet. Anhand der Ergebnisse werden die Wirksamkeit der Kühlung und ihr Optimierungspotential diskutiert.

Research paper thumbnail of Atomistic Modeling of Misfit Dislocation Network Variants for Ge/Si(111) Interfaces

Physica Status Solidi B-basic Solid State Physics, Nov 1, 2000

ABSTRACT

Research paper thumbnail of Atomistic Modeling of Misfit Dislocations for Ge/(001)Si and Ge/(111)Si

Physica status solidi, 1999

ABSTRACT

Research paper thumbnail of Hydrogen storage in magnesium-based hydrides and hydride composites

Scripta Materialia, 2007

... very high storage capacities are composites with borohydrides, for example, MgH 2 + NaBH 4 ,M... more ... very high storage capacities are composites with borohydrides, for example, MgH 2 + NaBH 4 ,MgH 2 + LiBH 4 ... Because of the combination of low reaction enthalpies with theoretic reversible hydrogen ... of 5 K min −1 . The grey curve shows the first dehydrogenation upon heating ...

Research paper thumbnail of Thermal optimisation of metal hydride reactors for thermal energy storage applications

Sustainable Energy and Fuels, 2017

Metal hydrides (MHs) are promising candidates as thermal energy storage (TES) materials for conce... more Metal hydrides (MHs) are promising candidates as thermal energy storage (TES) materials for concentrated solar thermal applications. A key requirement for this technology is a high temperature heat transfer fluid (HTF) that can deliver heat to the MHs for storage during the day, and remove heat at night time to produce electricity. In this study, supercritical water was used as a HTF to heat a prototype thermochemical heat storage reactor filled with MgH 2 powder during H 2 sorption, rather than electrical heating of the MH reactor. This is beneficial as the HTF flows through a coil of tubing embedded within the MH bed and is hence in better contact with the MgH 2 powder. This internal heating mode produces a more uniform temperature distribution within the reactor by increasing the heat exchange surface area and reducing the characteristic heat exchange distances. Moreover, supercritical water can be implemented as a heat carrier for the entire thermal energy system within a concentrating solar thermal plant, from the receiver, through the heat storage system, and also within a conventional turbine-driven electric power generation system. Thus, the total system energy efficiency can be improved by minimising HTF heat exchangers.

Research paper thumbnail of Nanostructured materials for solid-state hydrogen storage: A review of the achievement of COST Action MP1103

International Journal of Hydrogen Energy, Aug 1, 2016

In the framework of the European Cooperation in Science and Technology (COST) Action MP1103 Nanos... more In the framework of the European Cooperation in Science and Technology (COST) Action MP1103 Nanostructured Materials for Solid-State Hydrogen Storage were synthesized, characterized and modeled. This Action dealt with the state of the art of energy storage and set up a competitive and coordinated network capable to define new and unexplored ways for Solid State Hydrogen Storage by innovative and interdisciplinary research within the European Research Area. An important number of new compounds have been synthesized: metal hydrides, complex hydrides, metal halide ammines and amidoboranes. Tuning the structure from bulk to thin film, nanoparticles and nanoconfined composites improved the hydrogen sorption properties and opened the perspective to new technological applications. Direct imaging of the hydrogenation reactions and in situ measurements under operando conditions have been carried out in these studies. Computational screening methods allowed the prediction of suitable compounds for hydrogen storage and the modeling of the hydrogen sorption reactions on mono-, bi-, and three-dimensional systems. This manuscript presents a review of the main achievements of this Action.

Research paper thumbnail of Hydrogen storage in complex hydrides: past activities and new trends

Progress in Energy

Intense literature and research efforts have focussed on the exploration of complex hydrides for ... more Intense literature and research efforts have focussed on the exploration of complex hydrides for energy storage applications over the past decades. A focus was dedicated to the determination of their thermodynamic and hydrogen storage properties, due to their high gravimetric and volumetric hydrogen storage capacities, but their application has been limited because of harsh working conditions for reversible hydrogen release and uptake. The present review aims at appraising the recent advances on different complex hydride systems, coming from the proficient collaborative activities in the past years from the research groups led by the experts of the Task 40 ‘Energy Storage and Conversion Based on Hydrogen’ of the Hydrogen Technology Collaboration Programme of the International Energy Agency. An overview of materials design, synthesis, tailoring and modelling approaches, hydrogen release and uptake mechanisms and thermodynamic aspects are reviewed to define new trends and suggest new ...

Research paper thumbnail of XPS and TEM Study of the Oxygen Passivation Behaviour of Nanocrystalline Mg and MgH2

7th International Conference on Nanostructured Materials, 2004

Research paper thumbnail of Metal Hydride‐Based Hydrogen Storage Tank Coupled with an Urban Concept Fuel Cell Vehicle: Off Board Tests

Advanced Sustainable Systems, 2018

In this work, the tests of a hydrogen storage system intended for vehicular applications, using a... more In this work, the tests of a hydrogen storage system intended for vehicular applications, using a metal hydride as storage material, are reported. The system is designed to deliver gas to a fuel cell prototype vehicle. The room temperature hydride is an interstitial alloy, which is selected for its capacity to absorb and desorb hydrogen over an appropriate range of temperature and pressure. The static tests aim to assess whether the requirements for hydrogen release are reliably met by the tank setup. Hypothetical on‐road tests have been designed and applied. Dynamic tests allow moving from energy to power density. Solutions are adopted to face the issues of thermal management at higher‐demanding performances. Several cycles have been performed to find the ideal settings to preserve high average and peak gas flow in a realistic situation. The use of a metal hydride, to replace pressurized gas, results in improved performances, including an extended range at lower loading pressures. ...

Research paper thumbnail of On the Hydrogenation of a NaH/AlB2 Mixture

The Journal of Physical Chemistry C, 2015

A mixture of 3NaH/AlB 2 was prepared by ball-milling; its hydriding reaction was studied between ... more A mixture of 3NaH/AlB 2 was prepared by ball-milling; its hydriding reaction was studied between 375−425°C and 25−50 bar hydrogen pressure by means of volumetric titration. The hydriding reaction was characterized by means of in situ synchrotron radiation powder X-ray diffraction and high-pressure differential scanning calorimetry. Hydriding reaction took place at the molten state, and its reaction products were NaBH 4 and Al. The scanning electron microscopy images of the material revealed that the material morphology changes after hydriding. A maximum hydrogen uptake of 4.7 wt % was registered for the hydriding experiment at 425°C and 50 bar hydrogen pressure. Dehydriding reaction was studied by means of volumetric titration and differential scanning calorimetry. The dehydriding reaction at 425°C and 1 bar argon pressure registered a release of 2.4 wt %. The low dehydriding level was attributed to the reduction of the available particle surface upon melting of the material during the hydriding reaction.

Research paper thumbnail of Thermal and mechanically activated decomposition of LiAlH4

Materials Research Bulletin, 2008

Thermal stability of as-received LiAlH4 and milled LiAlH4 has been investigated. The thermal deco... more Thermal stability of as-received LiAlH4 and milled LiAlH4 has been investigated. The thermal decomposition mechanism of as-received LiAlH4 depends on the temperature–time history. Apparent activation energies and enthalpies of the reactions have been obtained. During milling treatment, the high temperature and pressures locally induced by shocks lead to LiAlH4 mechanically decomposition. The decomposition temperatures of LiAlH4 and Li3AlH6 are both

Research paper thumbnail of The catalytic effect of Nb2O5 on the electrochemical hydrogenation of nanocrystalline magnesium

Journal of Alloys and Compounds, 2006

Nanocrystalline Mg powder without and with 2 mol% Nb 2 O 5 catalyst was studied in a 6 M KOH elec... more Nanocrystalline Mg powder without and with 2 mol% Nb 2 O 5 catalyst was studied in a 6 M KOH electrolyte as electrode material for electrochemical hydrogen charging processes. Since the hydrogen overpotential of Mg, which is a measure of the hydrogen evolution at the electrode surface, was observed to be reduced by the addition of Nb 2 O 5 , it is assumed that the catalyst influences the electrode reactions. Considering this assumption hydrogenation was studied at different current densities. The storage capacity as well as the kinetic of Mg/Nb 2 O 5 electrodes increased significantly up to 1 wt.% H 2 at a charging time of 30 min with decreasing current density. The storage capacity of nanocrystalline Mg powder showed only minor changes to lower hydrogen contents with decreasing current density.

Research paper thumbnail of Catalyzed Na2LiAlH6 for hydrogen storage

Journal of Alloys and Compounds, 2005

In the present study, the complex alanate Na 2 LiAlH 6 is synthesized by high-energy milling of p... more In the present study, the complex alanate Na 2 LiAlH 6 is synthesized by high-energy milling of powder blends containing NaH and LiAlH 4. The related thermodynamics are determined. In addition, a comprehensive study was performed to investigate the influence of different oxide and halide catalysts on the kinetics of hydrogen absorption and desorption, as well as their general drawback to decrease storage capacity.

Research paper thumbnail of Mg-based compounds for hydrogen and energy storage

Applied Physics A, 2016

Magnesium-based alloys attract significant interest as cost-efficient hydrogen storage materials ... more Magnesium-based alloys attract significant interest as cost-efficient hydrogen storage materials allowing the combination of high gravimetric storage capacity of hydrogen with fast rates of hydrogen uptake and release and pronounced destabilization of the metalhydrogen bonding in comparison with binary Mg-H systems. In this review, various groups of magnesium compounds are considered, including (1) RE-Mg-Ni hydrides (RE = La, Pr, Nd); (2) Mg alloys with p-elements (X = Si, Ge, Sn, and Al); and (3) magnesium alloys with d-elements (Ti, Fe, Co, Ni, Cu, Zn, Pd). The hydrogenation-disproportionation-desorption-recombination process in the Mg-based alloys (LaMg 12 , LaMg 11 Ni) and unusually high-pressure hydrides synthesized at pressures exceeding 100 MPa (MgNi 2 H 3) and stabilized by Ni-H bonding are also discussed. The paper reviews interrelations between the properties of the Mg-based hydrides and p-T conditions of the metal-hydrogen interactions, chemical composition of the initial alloys, their crystal structures, and microstructural state.

Research paper thumbnail of Development and experimental validation of kinetic models for the hydrogenation/dehydrogenation of Mg/Al based metal waste for energy storage

Journal of Magnesium and Alloys, Oct 1, 2022

Research paper thumbnail of Ca(BH<sub>4</sub>)<sub>2</sub> + MgH<sub>2</sub>: Desorption Reaction and Role of Mg on Its Reversibility

Journal of Physical Chemistry C, Feb 15, 2013

The Ca(BH4)2–MgH2 composite system represents a promising candidate for mobile hydrogen storage d... more The Ca(BH4)2–MgH2 composite system represents a promising candidate for mobile hydrogen storage due to a 10.5 wt % theoretical hydrogen storage capacity and an estimated equilibrium temperature lower than 160 °C. For this system, the reversibility was achieved without further addition of additives. In this study, the decomposition path of the Ca(BH4)2 + MgH2 composite system is investigated in detail by in situ synchrotron radiation powder X-ray diffraction and differential scanning calorimetry combined with thermogravimetry. The sorption properties are analyzed by volumetric measurements. 11B{1H} solid state magic angle spinning–nuclear magnetic resonance was employed for the characterization of the final amorphous or nanocrystalline boron-based decomposition products. This study shows that the intermediate formation of Ca4Mg3H14 upon dehydrogenation of the Ca(BH4)2–MgH2 composite system is not a necessary step, and its presence can be adjusted modifying the preparation procedure. Moreover, the d-value m...

Research paper thumbnail of Novel type of high temperature heat exchanger for metal hydride stores; heat storage and Solid Oxide cells

Research paper thumbnail of Design and evaluation of a LiBH4 ‐ MgH2 storage system

Research paper thumbnail of Dynamics of porous and amorphous magnesium borohydride to understand solid state Mg-ion-conductors

Scientific Reports, Jun 3, 2020

Rechargeable solid-state magnesium batteries are considered for high energy density storage and u... more Rechargeable solid-state magnesium batteries are considered for high energy density storage and usage in mobile applications as well as to store energy from intermittent energy sources, triggering intense research for suitable electrode and electrolyte materials. Recently, magnesium borohydride, Mg(BH 4) 2 , was found to be an effective precursor for solid-state Mg-ion conductors. During the mechanochemical synthesis of these Mg-ion conductors, amorphous Mg(BH 4) 2 is typically formed and it was postulated that this amorphous phase promotes the conductivity. Here, electrochemical impedance spectroscopy of as-received γ-Mg(BH 4) 2 and ball milled, amorphous Mg(BH 4) 2 confirmed that the conductivity of the latter is ~2 orders of magnitude higher than in as-received γ-Mg(BH 4) 2 at 353 K. Pair distribution function (PDF) analysis of the local structure shows striking similarities up to a length scale of 5.1 Å, suggesting similar conduction pathways in both the crystalline and amorphous sample. Up to 12.27 Å the PDF indicates that a 3D net of interpenetrating channels might still be present in the amorphous phase although less ordered compared to the as-received γ-phase. However, quasi elastic neutron scattering experiments (QenS) were used to study the rotational mobility of the [BH 4 ] units, revealing a much larger fraction of activated [BH 4 ] rotations in amorphous Mg(BH 4) 2. These findings suggest that the conduction process in amorphous Mg(BH 4) 2 is supported by stronger rotational mobility, which is proposed to be the so-called "paddle-wheel" mechanism. Energy storage is one of the grand challenges for present and future generations. In recent years, intermittent renewable energy production has increased worldwide resulting in a high demand for energy storage systems. "Beyond Li-batteries", which are all-solid-state batteries with alternative working ions, including Na and Mg, are considered a promising alternative as they are cheaper and with respect to their natural abundancy more sustainable. However, the transport properties of larger Na + or double-charged Mg 2+ are challenging and directly correlated to the underlying crystal structure and dynamics. Understanding the accompanying structural and dynamic changes as well as finding high-performance cathode materials remain bottlenecks for the improvement of Mg-ion batteries 1. Mg-ion batteries (MIBs) have several advantages compared to Li-ion technology 2. For instance, the low electrochemical potential of −2.4 V (vs. standard hydrogen electrode (SHE)) is close to the one of Li with −3.0 V of Li/Li + , which allows for high cell voltages. Furthermore, Mg metal has a higher volumetric capacity of 3833 mA•cm −3 compared to 2036 mAh•cm −3 of Li metal, and magnesium has a higher natural abundancy of

Research paper thumbnail of Optimization and comprehensive characterization of a faithful tissue culture model of the benign and malignant human prostate

Laboratory Investigation, 2013

Few preclinical models accurately depict normal human prostate tissue or primary prostate cancer ... more Few preclinical models accurately depict normal human prostate tissue or primary prostate cancer (PCa). In vitro systems typically lack complex cellular interactions among structured prostatic epithelia and a stromal microenvironment, and genetic and molecular fidelity are concerns in both in vitro and in vivo models. 'Tissue slice cultures' (TSCs) provide realistic preclinical models of diverse tissues and organs, but have not been fully developed or widely utilized for prostate studies. Problems encountered include degeneration of differentiated secretory cells, basal cell hyperplasia, and poor survival of PCa. Here, we optimized, characterized, and applied a TSC model of primary human PCa and benign prostate tissue that overcomes many deficiencies of current in vitro models. Tissue cores from fresh prostatectomy specimens were precision-cut at 300 mm and incubated in a rotary culture apparatus. The ability of varied culture conditions to faithfully maintain benign and cancer cell and tissue structure and function over time was evaluated by immunohistological and biochemical assays. After optimization of the culture system, molecular and cellular responses to androgen ablation and to piperlongumine (PL), purported to specifically reduce androgen signaling in PCa, were investigated. Optimized culture conditions successfully maintained the structural and functional fidelity of both benign and PCa TSCs for 5 days. TSCs exhibited androgen dependence, appropriately undergoing ductal degeneration, reduced proliferation, and decreased prostate-specific antigen expression upon androgen ablation. Further, TSCs revealed cancer-specific reduction of androgen receptor and increased apoptosis upon treatment with PL, validating data from cell lines. We demonstrate a TSC model that authentically recapitulates the structural, cellular, and genetic characteristics of the benign and malignant human prostate, androgen dependence of the native tissue, and cancer-specific response to a potentially new therapeutic for PCa. The work described herein provides a basis for advancing the experimental utility of the TSC model.

Research paper thumbnail of Modellgestützte verfahrenstechnische Berechnung eines Metallhydridspeichers auf Natriumalanatbasis im Technikumsmaßstab

Chemie Ingenieur Technik, May 1, 2009

Im Rahmen des EU-Projekts STORHY ist der Prototyp eines Metallhydridspeichers auf Natriumalanatba... more Im Rahmen des EU-Projekts STORHY ist der Prototyp eines Metallhydridspeichers auf Natriumalanatbasis für automobile Anwendungen entwickelt worden. Besonderes Merkmal ist die Größe im Vergleich zu bisher vorhandenen Laborreaktoren. Mit Hilfe einer modellgestützten Simulation wird sein Beladungsverhalten für verschiedene Betriebsbedingungen berechnet. Anhand der Ergebnisse werden die Wirksamkeit der Kühlung und ihr Optimierungspotential diskutiert.

Research paper thumbnail of Atomistic Modeling of Misfit Dislocation Network Variants for Ge/Si(111) Interfaces

Physica Status Solidi B-basic Solid State Physics, Nov 1, 2000

ABSTRACT

Research paper thumbnail of Atomistic Modeling of Misfit Dislocations for Ge/(001)Si and Ge/(111)Si

Physica status solidi, 1999

ABSTRACT

Research paper thumbnail of Hydrogen storage in magnesium-based hydrides and hydride composites

Scripta Materialia, 2007

... very high storage capacities are composites with borohydrides, for example, MgH 2 + NaBH 4 ,M... more ... very high storage capacities are composites with borohydrides, for example, MgH 2 + NaBH 4 ,MgH 2 + LiBH 4 ... Because of the combination of low reaction enthalpies with theoretic reversible hydrogen ... of 5 K min −1 . The grey curve shows the first dehydrogenation upon heating ...

Research paper thumbnail of Thermal optimisation of metal hydride reactors for thermal energy storage applications

Sustainable Energy and Fuels, 2017

Metal hydrides (MHs) are promising candidates as thermal energy storage (TES) materials for conce... more Metal hydrides (MHs) are promising candidates as thermal energy storage (TES) materials for concentrated solar thermal applications. A key requirement for this technology is a high temperature heat transfer fluid (HTF) that can deliver heat to the MHs for storage during the day, and remove heat at night time to produce electricity. In this study, supercritical water was used as a HTF to heat a prototype thermochemical heat storage reactor filled with MgH 2 powder during H 2 sorption, rather than electrical heating of the MH reactor. This is beneficial as the HTF flows through a coil of tubing embedded within the MH bed and is hence in better contact with the MgH 2 powder. This internal heating mode produces a more uniform temperature distribution within the reactor by increasing the heat exchange surface area and reducing the characteristic heat exchange distances. Moreover, supercritical water can be implemented as a heat carrier for the entire thermal energy system within a concentrating solar thermal plant, from the receiver, through the heat storage system, and also within a conventional turbine-driven electric power generation system. Thus, the total system energy efficiency can be improved by minimising HTF heat exchangers.

Research paper thumbnail of Nanostructured materials for solid-state hydrogen storage: A review of the achievement of COST Action MP1103

International Journal of Hydrogen Energy, Aug 1, 2016

In the framework of the European Cooperation in Science and Technology (COST) Action MP1103 Nanos... more In the framework of the European Cooperation in Science and Technology (COST) Action MP1103 Nanostructured Materials for Solid-State Hydrogen Storage were synthesized, characterized and modeled. This Action dealt with the state of the art of energy storage and set up a competitive and coordinated network capable to define new and unexplored ways for Solid State Hydrogen Storage by innovative and interdisciplinary research within the European Research Area. An important number of new compounds have been synthesized: metal hydrides, complex hydrides, metal halide ammines and amidoboranes. Tuning the structure from bulk to thin film, nanoparticles and nanoconfined composites improved the hydrogen sorption properties and opened the perspective to new technological applications. Direct imaging of the hydrogenation reactions and in situ measurements under operando conditions have been carried out in these studies. Computational screening methods allowed the prediction of suitable compounds for hydrogen storage and the modeling of the hydrogen sorption reactions on mono-, bi-, and three-dimensional systems. This manuscript presents a review of the main achievements of this Action.

Research paper thumbnail of Hydrogen storage in complex hydrides: past activities and new trends

Progress in Energy

Intense literature and research efforts have focussed on the exploration of complex hydrides for ... more Intense literature and research efforts have focussed on the exploration of complex hydrides for energy storage applications over the past decades. A focus was dedicated to the determination of their thermodynamic and hydrogen storage properties, due to their high gravimetric and volumetric hydrogen storage capacities, but their application has been limited because of harsh working conditions for reversible hydrogen release and uptake. The present review aims at appraising the recent advances on different complex hydride systems, coming from the proficient collaborative activities in the past years from the research groups led by the experts of the Task 40 ‘Energy Storage and Conversion Based on Hydrogen’ of the Hydrogen Technology Collaboration Programme of the International Energy Agency. An overview of materials design, synthesis, tailoring and modelling approaches, hydrogen release and uptake mechanisms and thermodynamic aspects are reviewed to define new trends and suggest new ...

Research paper thumbnail of XPS and TEM Study of the Oxygen Passivation Behaviour of Nanocrystalline Mg and MgH2

7th International Conference on Nanostructured Materials, 2004

Research paper thumbnail of Metal Hydride‐Based Hydrogen Storage Tank Coupled with an Urban Concept Fuel Cell Vehicle: Off Board Tests

Advanced Sustainable Systems, 2018

In this work, the tests of a hydrogen storage system intended for vehicular applications, using a... more In this work, the tests of a hydrogen storage system intended for vehicular applications, using a metal hydride as storage material, are reported. The system is designed to deliver gas to a fuel cell prototype vehicle. The room temperature hydride is an interstitial alloy, which is selected for its capacity to absorb and desorb hydrogen over an appropriate range of temperature and pressure. The static tests aim to assess whether the requirements for hydrogen release are reliably met by the tank setup. Hypothetical on‐road tests have been designed and applied. Dynamic tests allow moving from energy to power density. Solutions are adopted to face the issues of thermal management at higher‐demanding performances. Several cycles have been performed to find the ideal settings to preserve high average and peak gas flow in a realistic situation. The use of a metal hydride, to replace pressurized gas, results in improved performances, including an extended range at lower loading pressures. ...

Research paper thumbnail of On the Hydrogenation of a NaH/AlB2 Mixture

The Journal of Physical Chemistry C, 2015

A mixture of 3NaH/AlB 2 was prepared by ball-milling; its hydriding reaction was studied between ... more A mixture of 3NaH/AlB 2 was prepared by ball-milling; its hydriding reaction was studied between 375−425°C and 25−50 bar hydrogen pressure by means of volumetric titration. The hydriding reaction was characterized by means of in situ synchrotron radiation powder X-ray diffraction and high-pressure differential scanning calorimetry. Hydriding reaction took place at the molten state, and its reaction products were NaBH 4 and Al. The scanning electron microscopy images of the material revealed that the material morphology changes after hydriding. A maximum hydrogen uptake of 4.7 wt % was registered for the hydriding experiment at 425°C and 50 bar hydrogen pressure. Dehydriding reaction was studied by means of volumetric titration and differential scanning calorimetry. The dehydriding reaction at 425°C and 1 bar argon pressure registered a release of 2.4 wt %. The low dehydriding level was attributed to the reduction of the available particle surface upon melting of the material during the hydriding reaction.

Research paper thumbnail of Thermal and mechanically activated decomposition of LiAlH4

Materials Research Bulletin, 2008

Thermal stability of as-received LiAlH4 and milled LiAlH4 has been investigated. The thermal deco... more Thermal stability of as-received LiAlH4 and milled LiAlH4 has been investigated. The thermal decomposition mechanism of as-received LiAlH4 depends on the temperature–time history. Apparent activation energies and enthalpies of the reactions have been obtained. During milling treatment, the high temperature and pressures locally induced by shocks lead to LiAlH4 mechanically decomposition. The decomposition temperatures of LiAlH4 and Li3AlH6 are both

Research paper thumbnail of The catalytic effect of Nb2O5 on the electrochemical hydrogenation of nanocrystalline magnesium

Journal of Alloys and Compounds, 2006

Nanocrystalline Mg powder without and with 2 mol% Nb 2 O 5 catalyst was studied in a 6 M KOH elec... more Nanocrystalline Mg powder without and with 2 mol% Nb 2 O 5 catalyst was studied in a 6 M KOH electrolyte as electrode material for electrochemical hydrogen charging processes. Since the hydrogen overpotential of Mg, which is a measure of the hydrogen evolution at the electrode surface, was observed to be reduced by the addition of Nb 2 O 5 , it is assumed that the catalyst influences the electrode reactions. Considering this assumption hydrogenation was studied at different current densities. The storage capacity as well as the kinetic of Mg/Nb 2 O 5 electrodes increased significantly up to 1 wt.% H 2 at a charging time of 30 min with decreasing current density. The storage capacity of nanocrystalline Mg powder showed only minor changes to lower hydrogen contents with decreasing current density.

Research paper thumbnail of Catalyzed Na2LiAlH6 for hydrogen storage

Journal of Alloys and Compounds, 2005

In the present study, the complex alanate Na 2 LiAlH 6 is synthesized by high-energy milling of p... more In the present study, the complex alanate Na 2 LiAlH 6 is synthesized by high-energy milling of powder blends containing NaH and LiAlH 4. The related thermodynamics are determined. In addition, a comprehensive study was performed to investigate the influence of different oxide and halide catalysts on the kinetics of hydrogen absorption and desorption, as well as their general drawback to decrease storage capacity.

Research paper thumbnail of Mg-based compounds for hydrogen and energy storage

Applied Physics A, 2016

Magnesium-based alloys attract significant interest as cost-efficient hydrogen storage materials ... more Magnesium-based alloys attract significant interest as cost-efficient hydrogen storage materials allowing the combination of high gravimetric storage capacity of hydrogen with fast rates of hydrogen uptake and release and pronounced destabilization of the metalhydrogen bonding in comparison with binary Mg-H systems. In this review, various groups of magnesium compounds are considered, including (1) RE-Mg-Ni hydrides (RE = La, Pr, Nd); (2) Mg alloys with p-elements (X = Si, Ge, Sn, and Al); and (3) magnesium alloys with d-elements (Ti, Fe, Co, Ni, Cu, Zn, Pd). The hydrogenation-disproportionation-desorption-recombination process in the Mg-based alloys (LaMg 12 , LaMg 11 Ni) and unusually high-pressure hydrides synthesized at pressures exceeding 100 MPa (MgNi 2 H 3) and stabilized by Ni-H bonding are also discussed. The paper reviews interrelations between the properties of the Mg-based hydrides and p-T conditions of the metal-hydrogen interactions, chemical composition of the initial alloys, their crystal structures, and microstructural state.

Research paper thumbnail of Development and experimental validation of kinetic models for the hydrogenation/dehydrogenation of Mg/Al based metal waste for energy storage

Journal of Magnesium and Alloys, Oct 1, 2022

Research paper thumbnail of Ca(BH<sub>4</sub>)<sub>2</sub> + MgH<sub>2</sub>: Desorption Reaction and Role of Mg on Its Reversibility

Journal of Physical Chemistry C, Feb 15, 2013

The Ca(BH4)2–MgH2 composite system represents a promising candidate for mobile hydrogen storage d... more The Ca(BH4)2–MgH2 composite system represents a promising candidate for mobile hydrogen storage due to a 10.5 wt % theoretical hydrogen storage capacity and an estimated equilibrium temperature lower than 160 °C. For this system, the reversibility was achieved without further addition of additives. In this study, the decomposition path of the Ca(BH4)2 + MgH2 composite system is investigated in detail by in situ synchrotron radiation powder X-ray diffraction and differential scanning calorimetry combined with thermogravimetry. The sorption properties are analyzed by volumetric measurements. 11B{1H} solid state magic angle spinning–nuclear magnetic resonance was employed for the characterization of the final amorphous or nanocrystalline boron-based decomposition products. This study shows that the intermediate formation of Ca4Mg3H14 upon dehydrogenation of the Ca(BH4)2–MgH2 composite system is not a necessary step, and its presence can be adjusted modifying the preparation procedure. Moreover, the d-value m...

Research paper thumbnail of Novel type of high temperature heat exchanger for metal hydride stores; heat storage and Solid Oxide cells

Research paper thumbnail of Design and evaluation of a LiBH4 ‐ MgH2 storage system

Research paper thumbnail of Dynamics of porous and amorphous magnesium borohydride to understand solid state Mg-ion-conductors

Scientific Reports, Jun 3, 2020

Rechargeable solid-state magnesium batteries are considered for high energy density storage and u... more Rechargeable solid-state magnesium batteries are considered for high energy density storage and usage in mobile applications as well as to store energy from intermittent energy sources, triggering intense research for suitable electrode and electrolyte materials. Recently, magnesium borohydride, Mg(BH 4) 2 , was found to be an effective precursor for solid-state Mg-ion conductors. During the mechanochemical synthesis of these Mg-ion conductors, amorphous Mg(BH 4) 2 is typically formed and it was postulated that this amorphous phase promotes the conductivity. Here, electrochemical impedance spectroscopy of as-received γ-Mg(BH 4) 2 and ball milled, amorphous Mg(BH 4) 2 confirmed that the conductivity of the latter is ~2 orders of magnitude higher than in as-received γ-Mg(BH 4) 2 at 353 K. Pair distribution function (PDF) analysis of the local structure shows striking similarities up to a length scale of 5.1 Å, suggesting similar conduction pathways in both the crystalline and amorphous sample. Up to 12.27 Å the PDF indicates that a 3D net of interpenetrating channels might still be present in the amorphous phase although less ordered compared to the as-received γ-phase. However, quasi elastic neutron scattering experiments (QenS) were used to study the rotational mobility of the [BH 4 ] units, revealing a much larger fraction of activated [BH 4 ] rotations in amorphous Mg(BH 4) 2. These findings suggest that the conduction process in amorphous Mg(BH 4) 2 is supported by stronger rotational mobility, which is proposed to be the so-called "paddle-wheel" mechanism. Energy storage is one of the grand challenges for present and future generations. In recent years, intermittent renewable energy production has increased worldwide resulting in a high demand for energy storage systems. "Beyond Li-batteries", which are all-solid-state batteries with alternative working ions, including Na and Mg, are considered a promising alternative as they are cheaper and with respect to their natural abundancy more sustainable. However, the transport properties of larger Na + or double-charged Mg 2+ are challenging and directly correlated to the underlying crystal structure and dynamics. Understanding the accompanying structural and dynamic changes as well as finding high-performance cathode materials remain bottlenecks for the improvement of Mg-ion batteries 1. Mg-ion batteries (MIBs) have several advantages compared to Li-ion technology 2. For instance, the low electrochemical potential of −2.4 V (vs. standard hydrogen electrode (SHE)) is close to the one of Li with −3.0 V of Li/Li + , which allows for high cell voltages. Furthermore, Mg metal has a higher volumetric capacity of 3833 mA•cm −3 compared to 2036 mAh•cm −3 of Li metal, and magnesium has a higher natural abundancy of