The effect of preparing lead-based organohalide perovskites under inert conditions has been investigated. We find that when prepared under anhydrous conditions, only poorly crystalline powders were obtained. On exposure to small amounts of moisture a rapid crystallization into the expected cubic unit cell for CH3NH3PbBr3 and tetragonal cell for CH3NH3PbI3 is observed. While the as-prepared iodide phase is non-emissive, the lifetime of the emission for the bromide is found to be much longer when prepared under atmospheric conditions.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/c4cc05231e | DOI Listing |
Nat Mater
January 2024
Department of Chemistry and Centre for Processable Electronics, Imperial College London, London, UK.
Vibrational control (VC) of photochemistry through the optical stimulation of structural dynamics is a nascent concept only recently demonstrated for model molecules in solution. Extending VC to state-of-the-art materials may lead to new applications and improved performance for optoelectronic devices. Metal halide perovskites are promising targets for VC due to their mechanical softness and the rich array of vibrational motions of both their inorganic and organic sublattices.
View Article and Find Full Text PDFMaterials (Basel)
October 2023
Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland.
Polyhedral oligomeric silsesquioxanes (POSS) and hybrid organo-halide perovskites are two important types of hybrid nanoscale frameworks with great potential in materials chemistry. Both are currently under intensive investigation for a wide range of possible applications. Recent results suggest that POSS can be attractive passivating and structure-controlling agents for perovskite materials.
View Article and Find Full Text PDFChemSusChem
January 2024
Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA-92182, USA.
Visible-light-induced halide-exchange between halide perovskite and organohalide solvents has been studied in which photoinduced electron transfer from CsPbBr nanocrystals (NCs) to dihalomethane solvent molecules produces halide anions via reductive dissociation, followed by a spontaneous anion-exchange. Photogenerated holes in this process are less focused. Here, for CsPbBr in dibromomethane (DBM), we discover that Br radical (Br⋅) is a key intermediate resulting from the hole oxidation.
View Article and Find Full Text PDFNanoscale
March 2023
AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
Two-dimensional (2D) lead halide perovskites are an exciting class of materials currently being extensively explored for photovoltaics and other optoelectronic applications. Their ionic nature makes them ideal candidates for solution processing into both thin films and nanostructured crystals. Understanding how 2D lead halide perovskite crystals form is key towards full control over their physical properties, which may enable new physical phenomena and devices.
View Article and Find Full Text PDFOrganohalide perovskite materials and related optoelectronic applications have drawn significant attention due to their promising high-performance photon-to-electricity conversion efficiencies. Herein, we demonstrate a highly sensitive self-powered perovskite-based photodetector created with a noise-current-suppressible passivation layer of poly(methyl methacrylate) (PMMA) at the interface between a CHNHPbI light-absorbing layer and a NiO hole-transporting layer. Along with the defect passivation effect, the PMMA layer effectively diminishes unwanted carrier recombination losses at the interface, resulting in a significant reduction of the leakage/noise current.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!