Hiba Diab

Using Low Temperature Photoluminescence Spectroscopy to Investigate CH3NH3PbI3 Hybrid Perovskite Degradation

Investigating the stability and evaluating the quality of the CH3NH3PbI3 perovskite structures is quite critical both to the design and fabrication of high-performance perovskite devices and to fundamental studies of the photophysics of the excitons. In particular, it is known that, under ambient conditions, CH3NH3PbI3 degrades producing some PbI2. We show here that low temperature Photoluminescence (PL) spectroscopy is a powerful tool to detect PbI2 traces in hybrid perovskite layers and single crystals. Because PL spectroscopy is a signal detection method on a black background, small PbI2 traces can be detected, when other methods currently used at room temperature fail. Our study highlights the extremely high stability of the single crystals compared to the thin layers and defects and grain boundaries are thought to play an important role in the degradation mechanism.

Fast growth of monocrystalline thin films of 2D layered hybrid perovskite

Hybrid organic–inorganic perovskites are on the way to deeply transforming the photovoltaic domain. Likewise, it recently appeared that this class of material has a lot of potential for other optoelectronic applications. One key aspect is to be able to synthesize monocrystalline thin films with large surface areas. Here, we report on the development of a new synthesis method for 2D hybrid organic–inorganic perovskite called “Anti-solvent Vapor-assisted Capping Crystallization”. This method allows us to grow monocrystalline thin films with a high aspect ratio in less than 30 minutes.

Time-resolved photoemission spectroscopy of electronic cooling and localization in CH3NH3PbI3 crystals

We measure the surface of

Narrow Linewidth Excitonic Emission in Organic–Inorganic Lead Iodide Perovskite Single Crystals

{\mathrm{CH}}_{3}{\mathrm{NH}}_{3}{\mathrm{PbI}}_{3}

Room temperature cavity polaritons with 3D hybrid perovskite - Towards low-cost polaritonic devices

single crystals by making use of two-photon photoemission spectroscopy. Our method monitors the electronic distribution of photoexcited electrons, explicitly discriminating the initial thermalization from slower dynamical processes. The reported results disclose the fast-dissipation channels of hot carriers (0.25 ps), set an upper bound to the surface-induced recombination velocity

Les pérovskites hybrides halogénées: un nouveau semiconducteur pour le photovoltaïque et l'émission de lumière

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Excitonic emission of hybrid lead iodide perovskite single crystals.

cm/s), and reveal the dramatic effect of shallow traps on the electrons dynamics. The picosecond localization of excited electrons in degraded

Impact of Reabsorption on the Emission Spectra and Recombination Dynamics of Hybrid Perovskite Single Crystals

{\mathrm{CH}}_{3}{\mathrm{NH}}_{3}{\mathrm{PbI}}_{3}

Excitonic Emission and Electron-Phonon coupling in Organic-Inorganic Lead Iodide Perovskite single crystals

samples is consistent with the progressive reduction of photoconversion efficiency in operating devices. Minimizing the density of shallow traps and solving the aging problem may boost the macroscopic efficiency of solar cells to the theoretical limit.