Related papers: Halide diffusion in mixed-halide perovskites and h…
The understanding of the mixed ionic-electronic nature of charge transport in Metal Halide Perovskites (MHPs) and the role of morphological and interface defects is crucial for improving the performance of MHP based photovoltaic devices. We…
Microscopic pathways of structural phase transitions are difficult to probe because they occur over multiple, disparate time and length scales. Using $in$ $situ$ nanoscale cathodoluminescence microscopy, we visualize the thermally-driven…
Here we develop a microscopic approach aimed at the description of a suite of physical effects related to carrier transport in, and the optical properties of, halide perovskites. Our theory is based on the description of the nuclear…
Halide pervoskites are an important class of semiconducting materials which hold great promise for optoelectronic applications. In this work we investigate the relationship between vibrational anharmonicity and dynamic disorder in this…
The use of methylammonium (MA) lead halide perovskites \ce{CH3NH3PbX3} (X=I, Br, Cl) in perovskite solar cells (PSCs) has made great progress in performance efficiency during recent years. However, the rapid decomposition of \ce{MAPbI3} in…
Mixed-halide perovskites (MHPs) offer good band gap tunability by stoichiometry changes, which is an essential property for the creation of multijunction solar cells. However, under illumination, halide ions in MHP segregate and create I-…
It is now widely recognized that surface and interfacial defects exhibit distinct behavior compared to bulk defects in metal halide perovskites. However, the transition from bulk to surface behavior and the spatial extent of the surface's…
Halide perovskite and elpasolite semiconductors are extensively studied for optoelectronic applications due to their excellent performance together with significant chemical and structural flexibility. However, there is still limited…
We investigate the impact of various levels of approximation in density functional theory calculations for the structural and binding properties of the prototypical halide perovskite MAPbI$_3$. Specifically, we test how the inclusion of…
Photo- and charge-carrier induced ion migration is a major challenge when utilizing metal halide perovskite semiconductors for optoelectronic applications. For mixed iodide/bromide perovskites, the compositional instability due to light- or…
We characterized the formation of vacancies at a surface slab model and contrasted the results with the bulk of lead-halide perovskites using cubic and tetragonal CsPbI$_3$ as representative structures. The defect-free CsI-terminated (100)…
Interaction between hydrogen (H) and metals is central to many materials problems of scientific and technological importance. Chief among them is the development of H storage and H-resistant materials. H segregation or trapping at lattice…
Ionic migration in organo-halide perovskites plays an important role in operation of perovskite based solar cells and light emitting diodes. Despite the ionic migration being a reversible process, it often leads to worsening of perovskite…
The diffusion of intrinsic defects in 3C-SiC is studied using an ab initio method based on density functional theory. The vacancies are shown to migrate on their own sublattice. The carbon split-interstitials and the two relevant silicon…
Gradual reverse-bias breakdown in metal-halide perovskite diodes and solar cells is thought to originate from hole tunneling through steep bands in an ionic depletion region near the electron transport layer after positively charged iodine…
Tuning the thermal transport properties of hybrid halide perovskites is critical for their applications in optoelectronics, thermoelectrics, and photovoltaics. Here, we demonstrate an effective strategy to modulate the thermal transport…
Density-functional theory calculations based on conventional as well as hybrid exchange-correlation functionals have been carried out to study the properties of helium in various oxides (Al2O3, TiO2, Y2O3, YAP, YAG, YAM, MgO, CaO, BaO, SrO)…
Hybrid halide perovskite semiconductors exhibit complex, dynamical disorder while also harboring properties ideal for optoelectronic applications that include photovoltaics. However, these materials are structurally and compositionally…
The standard model of enhanced ionic conductivities in solid electrolyte heterostructures follows from a continuum mean-field description of defect distributions that makes no reference to crystalline structure. To examine ionic transport…
Metal halide perovskite-based semi-conducting hetero-structures have emerged as promising electronics for solar cells, light-emitting diodes, detectors, and photo-catalysts. Perovskites' efficiency, electronic properties and their long-term…