Sökning: "halide perovskites"

Visar resultat 1 - 5 av 28 avhandlingar innehållade orden halide 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. 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

  5. 4. The life and death of perovskites : Interfacial function and degradation of lead halide perovskites studied by photoelectron spectroscopy

    Författare :Sebastian Svanström; Ute B Cappel; Håkan Rensmo; Erik Johansson; Selina Olthof; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lead halide perovskite solar cells; interfacial degradation; heterojunction interfaces; photoelectron spectroscopy; operando; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : Lead halide perovskite solar cells are a promising new technology which could soon see widespread commercial application but is partly held back by poor long-term stability. In this thesis, photoelectron spectroscopy (PES) is used to study the dynamical processes at the surface or interfaces of lead halide perovskite materials. LÄS MER

  7. 5. Bandgap Engineering of Lead-Free Halide Double Perovskites

    Författare :Fuxiang Ji; Feng Gao; Feng Wang; Niclas Solin; David Mitzi; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Lead-free halide double perovskites; Metal doping alloying; Bandgap engineering; Atomic-level structure; Thermochromism;

    Sammanfattning : Lead-free halide double perovskites (HDPs, A2BIBIIIX6) with attractive optical and electronic features are regarded as one of the most promising alternatives to overcome the toxicity and stability issues of lead halide perovskites. They provide a wide range of possible combinations and rich substitutional chemistry with interesting properties for various optoelectronic devices. LÄS MER