Structural and optical properties of MgxAl1-xHy gradient thin films: a combinatorial approach

Gremaud, Robin; Borgschulte, Andreas; Mechelen, J. L. M. van; Schreuders, Herman; Züttel, Andreas; Hjörvarsson, Bjørgvin; Dam, B.; Griessen, R.

doi:10.1007/s00339-006-3579-z

Cited by 34 publications

(32 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With a straightforward optical setup, hydrogenography makes it possible to monitor hydrogen ab-and desorption simultaneously on thousands of samples under exactly the same experimental conditions. [8][9][10] We show here that hydrogenography is much more than a monitoring technique, as it also provides a high-throughput method to measure quantitatively the key thermodynamic properties (enthalpy and entropy) of hydride formation. We describe the essential ingredients of hydrogenography with the Mg-Ti-H system and demonstrate its combinatorial power with the Mg-Ti-Ni-H system.…”

mentioning

confidence: 97%

Hydrogenography: An Optical Combinatorial Method To Find New Light‐Weight Hydrogen‐Storage Materials

et al. 2007

Self Cite

View full text Add to dashboard Cite

The standard approach for the search of new hydrogen-storage materials is to synthesize bulk samples and to use volumetric [1,2] or gravimetric [3] techniques to follow their hydrogenation reaction and to record pressure-concentration isotherms (p-c isotherms). The equilibrium pressure of the metal-to-hydride transition is determined from the plateau of the p-c isotherm. The enthalpy of hydride formation is extracted from the temperature dependence of the equilibrium pressure, by means of the Van 't Hoff relation [4] lnwhere DH is the enthalpy of formation in kJ (mol H 2 ) -1 , DS 0 is the entropy of formation in JK -1 (mol H 2 ) -1 at standard pressure, R the gas constant, the absolute temperature, p 0 = 1.013 × 10 5 Pa the standard pressure, and p eq the H 2 equilibrium plateau pressure of the p-c isotherm. The great disadvantage of this approach is that a bulk sample is needed for each investigated chemical composition. Thin films provide an interesting alternative to bulk, as their nanostructure is controlled by the deposition conditions. Because of the small amount of material and large surfaces present, diffusion and local heating issues are minimized, the kinetics are fast, and the measurement time is reduced drastically. [5] Moreover, a large number of different chemical compositions can be deposited on a single substrate in a combinatorial way. The fact that hydrogen absorption in a metal leads to large optical changes [6,7] is the basis of a new combinatorial method that we call hydrogenography. With a straightforward optical setup, hydrogenography makes it possible to monitor hydrogen ab-and desorption simultaneously on thousands of samples under exactly the same experimental conditions. [8][9][10] We show here that hydrogenography is much more than a monitoring technique, as it also provides a high-throughput method to measure quantitatively the key thermodynamic properties (enthalpy and entropy) of hydride formation. We describe the essential ingredients of hydrogenography with the Mg-Ti-H system and demonstrate its combinatorial power with the Mg-Ti-Ni-H system. We show in particular that there is a relatively narrow range of compositions in the ternary Mg-Ti-Ni phase diagram with a remarkable combination of favorable properties for light-weight hydrogen storage. Pure MgH 2 would in principle be an attractive system for hydrogen storage as it can contain as much as 7.6 wt % of hydrogen. However, its large negative enthalpy of formation (-74 kJ (mol H 2 ) -1

show abstract

mentioning

confidence: 97%

Hydrogenography: An Optical Combinatorial Method To Find New Light‐Weight Hydrogen‐Storage Materials

et al. 2007

Self Cite

View full text Add to dashboard Cite

show abstract

“…326 Hydrogenography has also been utilized as a switchable mirror technology, taking advantage of the change in transmissivity that results from hydrogenation, as well as other applications. [327][328][329][330] Hydrogenography has been applied for compositional mapping of a number of Mg based systems such as Mg-Ni, 309,331 Mg-Ni-Ti, 332 Mg-Al, 333 and Mg-Al-Ti. 334 A notable result from this body of work was the discovery 316 of the alloy Mg 69 Ni 26 Ti 5 , Fig.…”

Section: Thin Film Combinatorial Workmentioning

confidence: 99%

Applications of high throughput (combinatorial) methodologies to electronic, magnetic, optical, and energy-related materials

Green

Takeuchi

Hattrick‐Simpers

2013

Journal of Applied Physics

227

189

View full text Add to dashboard Cite

High throughput (combinatorial) materials science methodology is a relatively new research paradigm that offers the promise of rapid and efficient materials screening, optimization, and discovery. The paradigm started in the pharmaceutical industry but was rapidly adopted to accelerate materials research in a wide variety of areas. High throughput experiments are characterized by synthesis of a "library" sample that contains the materials variation of interest (typically composition), and rapid and localized measurement schemes that result in massive data sets. Because the data are collected at the same time on the same "library" sample, they can be highly uniform with respect to fixed processing parameters. This article critically reviews the literature pertaining to applications of combinatorial materials science for electronic, magnetic, optical, and energy-related materials. It is expected that high throughput methodologies will facilitate commercialization of novel materials for these critically important applications. Despite the overwhelming evidence presented in this paper that high throughput studies can effectively inform commercial practice, in our perception, it remains an underutilized research and development tool. Part of this perception may be due to the inaccessibility of proprietary industrial research and development practices, but clearly the initial cost and availability of high throughput laboratory equipment plays a role. Combinatorial materials science has traditionally been focused on materials discovery, screening, and optimization to combat the extremely high cost and long development times for new materials and their introduction into commerce. Going forward, combinatorial materials science will also be driven by other needs such as materials substitution and experimental verification of materials properties predicted by modeling and simulation, which have recently received much attention with the advent of the Materials Genome Initiative. Thus, the challenge for combinatorial methodology will be the effective coupling of synthesis, characterization and theory, and the ability to rapidly manage large amounts of data in a variety of formats. V C 2013 AIP Publishing LLC. [http://dx

show abstract

“…The nanocrystalline MgH 2 shows improved kinetics with a desorption temperature that is about 100 K less compared to that of the untreated conventional powder. Recently, co-sputtering of Mg and Al has been used to destabilize the Mg matrix and create nanocrystalline or amorphous thin films [8,9]. Recent neutron reflectometry (NR) experiments on thin MgAl films [10] confirmed that Mg 0.7 Al 0.3 is the optimum composition to maximize the stored hydrogen content (4.1 wt%) and minimize the desorption temperature (448 K).…”

Section: Introductionmentioning

confidence: 99%

Structural changes of thin MgAl films during hydrogen desorption

Fritzsche

Saoudi

Haagsma

et al. 2009

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues.Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. We used neutron reflectometry (NR) to study the structural changes of thin Pd-capped Mg 0.7 Al 0.3 and Mg 0.6 Al 0.4 alloy films after hydrogen absorption and during hydrogen desorption. NR enabled us to determine the hydrogen content and hydrogen distribution in these thin MgAl alloy films along with the structural changes associated with the desorption process. The thin films expand by about 20% during the hydrogen absorption and the hydrogen is stored only in the MgAl layer with no hydrogen content in the Pd layer. The Mg 0.7 Al 0.3 films are fully desorbed at 448 K, whereas for the Mg 0.6 Al 0.4 films a temperature of 473 K is needed to fully desorb the hydrogen. Our NR measurements show that the higher annealing temperature needed to desorb the hydrogen from the Mg 0.6 Al 0.4 films led to an interdiffusion of the Pd layer into the MgAl layer. This Pd interdiffusion was also observed in a Mg 0.7 Al 0.3 film after a 9 h annealing at 473 K. So, the Pd interdiffusion into a MgAl film that has been charged with hydrogen is a common feature of the Pd/Mg 0.7 Al 0.3 and Pd/Mg 0.6 Al 0.4 alloy system. In contrast, for the as-prepared hydrogen-free Pd/Mg 0.7 Al 0.3 film the Pd layer stays intact and only a small interdiffusion zone occurs at the Pd/MgAl interface. Crown

show abstract

Structural and optical properties of MgxAl1-xHy gradient thin films: a combinatorial approach

Cited by 34 publications

References 47 publications

Hydrogenography: An Optical Combinatorial Method To Find New Light‐Weight Hydrogen‐Storage Materials

Hydrogenography: An Optical Combinatorial Method To Find New Light‐Weight Hydrogen‐Storage Materials

Applications of high throughput (combinatorial) methodologies to electronic, magnetic, optical, and energy-related materials

Structural changes of thin MgAl films during hydrogen desorption

Contact Info

Product

Resources

About