Structural and electronic properties of magnesium–3D transition metal switchable mirrors

Farangis, Baker; Nachimuthu, Ponnusamy; Richardson, Thomas J.; Slack, Jonathan; Meyer, B.; Perera, R. C. C.; Rubín, M.

doi:10.1016/j.ssi.2003.08.041

Cited by 42 publications

(6 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Region a, on the other hand, presents a chemical shift of 2 eV compared to the spectrum of region b, which we attribute to the presence of TiH 2 (possibly including a partial Mg surrounding of the Ti, such as in the Mg 1-y Ti y H 2 phase). Indeed, in their X-ray absorption spectroscopy studies of Mg− Ti thin films, Farangis et al 31,35 report a small positive chemical shift for TiH 2 as compared to Ti metal.…”

Section: ■ Resultsmentioning

confidence: 99%

Reduced Enthalpy of Metal Hydride Formation for Mg–Ti Nanocomposites Produced by Spark Discharge Generation

et al. 2013

View full text Add to dashboard Cite

Spark discharge generation was used to synthesize Mg-Ti nanocomposites consisting primarily of a metastable body-centered-cubic (bcc) alloy of Mg and Ti. The bcc Mg-Ti alloy transformed upon hydrogenation into the face-centered-cubic fluorite Mg1-yTiyHx phase with favorable hydrogen storage properties. Both metal and metal hydride nanocomposites showed a fractal-like porous morphology, with a primary particle size of 10-20 nm. The metal content of 70 atom % (at %) Mg and 30 at % Ti, consistently determined by XRD, TEM-EDS, and ICP-OES, was distributed uniformly across the as-prepared sample. Pressure-composition isotherms for the Mg-Ti-H nanocomposites revealed large differences in the thermodynamics relative to bulk MgH2, with a much less negative enthalpy of formation of the hydride as small as -45 ± 3 kJ/molH2 as deduced from van't Hoff plots. The plateau pressures of hydrogenation were substantially higher than those for bulk MgH2 in the low temperature range from 150 to 250 °C. The reaction entropy was simultaneously reduced to values down to 84 ± 5 J/K mol H2, following a linear relationship between the enthalpy and entropy. Plausible mechanisms for the modified thermodynamics are discussed, including the effect of lattice strains, the presence of interfaces and hydrogen vacancies, and the formation of excess free volume due to local deformations. These mechanisms all rely on the finely interdispersed nanocomposite character of the samples which is maintained by grain refinement.

show abstract

Section: ■ Resultsmentioning

confidence: 99%

Reduced Enthalpy of Metal Hydride Formation for Mg–Ti Nanocomposites Produced by Spark Discharge Generation

et al. 2013

View full text Add to dashboard Cite

show abstract

“…Pd, due to its high hydrogen solubility and diffusivity, along with its high corrosion resistance, is a suitable element for various hydride material technologies like hydride batteries, optical switching devices, hydrogen purification membranes and hydrogen sensors. In particular, Pd has been used as the outermost layer in various hydriding rare earth and magnesium-based films [13][14][15][16][17][18][19][20][21][22][23]. Palladium has recently attracted much interest as a potential replacement for higher priced platinum in catalytic converters for controlling emissions from diesel vehicles.…”

Section: Introductionmentioning

confidence: 99%

Investigation of transmittance property of Palladium thin films fabricated by pulsed laser deposition with polarization using single layer model

Singh

Jha

Singh

et al. 2010

Optics & Laser Technology

View full text Add to dashboard Cite

“…This is covered with a thin buffer layer of MoO x . The last layers are the switchable rear contact, consisting of 24 ± 2 nm Mg with a 6 ± 2 nm Pd capping layer to prevent oxidation of Mg and to catalyze the absorption of hydrogen. , The MoO x layer is used to improve the band alignment between the low work function material Mg , and p-doped μc-Si. The device is illuminated from the glass side, meaning the cell is in superstrate configuration.…”

Section: Results and Discussionmentioning

confidence: 99%

Switchable Photocurrent Generation in an Ultrathin Resonant Cavity Solar Cell

Götz¹,

Lengert²,

Osterthun³

et al. 2020

ACS Photonics

View full text Add to dashboard Cite

Fabry-Perot type resonant nanocavities allow for broadband enhancement of light absorption in ultra-thin absorber layers. By introducing a switchable mirror, these thin film structures can be used as unique optical devices enabling interesting applications with switchable absorption. We use a thin film photovoltaic layer stack based on an amorphous germanium absorber layer and combine it with a thin Mg/Pd mirror to create a switchable solar cell. In this work we demonstrate, how we can switch the light absorption and hence the photocurrent generation of the thin film solar cell by changing the refractive index of Mg, due to hydrogen absorption. Our results show, how optical resonances in the absorber can be switched "on / off" by the change of optical properties of the magnesium reflector. The multi-layer system can be switched from a light absorbing and photocurrent generating state to a transparent window state with excellent color neutrality. We emphasize our study as an important step towards the realization of switchable photovoltaic windows, which paves the way for larger scale building integrated photovoltaic applications.

show abstract

Structural and electronic properties of magnesium–3D transition metal switchable mirrors

Cited by 42 publications

References 7 publications

Reduced Enthalpy of Metal Hydride Formation for Mg–Ti Nanocomposites Produced by Spark Discharge Generation

Reduced Enthalpy of Metal Hydride Formation for Mg–Ti Nanocomposites Produced by Spark Discharge Generation

Investigation of transmittance property of Palladium thin films fabricated by pulsed laser deposition with polarization using single layer model

Switchable Photocurrent Generation in an Ultrathin Resonant Cavity Solar Cell

Contact Info

Product

Resources

About