Sökning: "PEROVSKITES"

Visar resultat 1 - 5 av 63 avhandlingar innehållade ordet PEROVSKITES.

  1. 1. Neutron spectroscopy studies of vibrational and diffusional dynamics in organometal halide and oxyhydride perovskites

    Författare :Rasmus Lavén; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Metal halide perovskites; perovskites; phonons; quasielastic neutron scattering; inelastic neutron scattering; oxyhydrides; hydrogen dynamics.; diffusion;

    Sammanfattning : This thesis deals with inelastic and quasielastic neutron scattering studies on the dynamical properties of the organometal halide perovskite system MA1-xFAxPbI3 (MA = methylammonium; FA = formamidinium) and of the layered perovskite-type oxyhydride SrVO2H. These materials systems are of high interest for their excellent photovoltaic performance (MA1-xFAxPbI3) and hydride-ion conductivity (SrVO2H) and concomitant promise for various technological devices; however, the local structure and dynamics underpinning these materials properties remain unclear. LÄS MER

  3. 2. Modeling hybrid halide perovskites for solar cell applications : Simulations of electronic structure and X-ray spectroscopy

    Författare :Cody M. Sterling; Michael Odelius; Alison B. Walker; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Solar cells; perovskites; computational chemistry; simulations; electronic structure; density functional theory; X-ray spectroscopy; kemisk fysik; Chemical Physics;

    Sammanfattning : Over the past 13 years, perovskites have become a very promising candidate in the search for cheap and effective photovoltaic materials for solar cells.  Perovskite solar cell power conversion efficiency has increased from 3. LÄS MER

  4. 3. Vibrational proton dynamics in hydrated perovskites and alkali thio-hydroxogermanates

    Författare :Maths Karlsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fuel cell; proton conduction; perovskites; proton dynamics; thio-hydroxogermanates; vibrational spectroscopy;

    Sammanfattning : .... LÄS MER

  5. 4. Solid state proton conductors: hydrated perovskites and hydrated alkali thio-hydroxogermanates

    Författare :Maths Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; neutron scattering; vibrational spectroscopy; alkali thio-hydroxogermanates; Proton conductors; fuel cells.; perovskites;

    Sammanfattning : This thesis concerns experimental studies of hydrated perovskites and hydrated alkali thio-hydroxogermanates, two classes of solid state proton conductors which are promising to be used as electrolytes in future intermediate temperature (200-500°C) fuel cells.This is an attractive temperature range for many applications but for which today's available electrolytes do not show satisfactory performance. LÄS MER

  7. 5. Dynamics in Blue Emitting Metal Halide Perovskites for Light Emitting Diodes

    Författare :Max Karlsson; Feng Gao; Tze Chien Sum; Barry P. Rand; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Perovskites; Light-emitting diodes; Stability; Efficiency;

    Sammanfattning : Lighting comprises a large part of the global electricity consumption as of today, and the use of lighting in illumination and displays is only projected to grow. It is therefore imperative to meet this energy demand, not only by means of greener energy production, but also with materials that are both more efficient to fabricate as well as to use. LÄS MER