Скачать с ютуб Perovskites II; Crystals, Orbitals and Trap-states in Perovskites-Structural and Electronic Aspects в хорошем качестве

Perovskites II; Crystals, Orbitals and Trap-states in Perovskites-Structural and Electronic Aspects

#perovskite #solar #photovoltaics #nanomaterials #solarcell #education #photochemistry #orbitals #structure This is a recorded Zoom lecture at the MSc level for chemistry students that are interested in Nanotechnology and Supramolecular Chemistry. Nanotechnology and Nanomaterials. Photoactive Nanomaterials. There are ~15 video's in this course In this second lecture on perovskites structural factors that are important in lead halide perovskites for solar cell materials are discussed. Focus is on FAPbI3, formamidinium lead tri-iodides. The black alpha phase, the conversion to the yellow (inactive) delta phase as well as the importance of intact octahedra are highlighted. The orbitals describing the valence band and conduction band are discussed, as well as the nature of trap states and their correlation to the factors described above. From The first lecture on Perovskites: This lecture introduces the Perovskites as a solar cell materials. Their structure and components are discussed. Than focus is on doping with zinc (II) ions as well as other lattice strain releasing small ions. Learning objectives: Perovskites have the steepest rise of efficiency vs time of all solar cell materials. It is expected that they will surpass silicon in the coming years. Pb(II) is related to all high efficiency compositions, but Sn(II) can also be used (as B), next to methylammonium, formamidinium, ceasium and rubidium as monovalent cations (as A). Halogens form the anions (X), and strongly influence the bandgap. Iodides are most strongly colored ABX3 materials. Doping of perovskites can strongly influence their properties. Methylammonium is the weakest component and should be avoided. This is our (Open Access) work on Perovskites: https://doi.org/10.1021/acsami.9b03810 https://doi.org/10.3390/app10093061 https://doi.org/10.3390/app9081678 https://doi.org/10.26434/chemrxiv.548... https://doi.org/10.13140/RG.2.1.1406.... With the latest addition: https://encyclopedia.pub/1266 (with in Bold, some extra info). For more information on the weak points of Methyl ammonium: Korean group with Sang Il Seok: https://doi.org/10.1002/adma.201805337 Grätzel, Saliba: https://doi.org/10.1016/j.mattod.2018... Science paper on MA fumigation: https://doi.org/10.1126/science.aba2412 Saliba: https://doi.org/10.1126/science.aat3583 See also Grätzel at &t=2560:    • Michael Grätzel | Molecular Photovolt...   (at 42:40) NEW: see also Peer review file of recent Nat Comm. paper of René Janssen: https://www.nature.com/articles/s4146... https://doi.org/10.1038/s41467-020-19... "Indeed, it is widely accepted in the research society that MA-based perovskites are less stable concerning humidity and thermal stress". For more information on Perovskites in general: Special issue of Account of Chemical Research on Perovskites: https://doi.org/10.1021/acs.accounts.... EES: https://doi.org/10.1039/C6EE03397K Mat. Today: https://doi.org/10.1016/j.mtener.2018... It was recently shown that Bi doping only induces structural defects that lead to additional defect states: https://pubs.acs.org/doi/10.1021/jacs... rubidium in halide perovskites been disproved: https://onlinelibrary.wiley.com/doi/a... QUIZ 1: Which pop-song title did I use in this talk? QUIZ 2: Is there new information on the composition of recent record materials? QUIZ 3: How much current (mA/cm^2) would a perovskite cell give if it would reach the Shockley Queisser limit? (if it gives 1.1 V). Perovskite talk 1 F EDITED