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      Chemical Analysis of the Interface between Hybrid Organic–Inorganic Perovskite and Atomic Layer Deposited Al 2O 3

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          Ultrathin metal oxides prepared by atomic layer deposition (ALD) have gained utmost attention as moisture and thermal stress barrier layers in perovskite solar cells (PSCs). We have recently shown that 10 cycles of ALD Al 2O 3 deposited directly on top of the CH 3NH 3PbI 3– x Cl x perovskite material, are effective in delivering a superior PSC performance with 18% efficiency (compared to 15% of the Al 2O 3-free cell) with a long-term humidity-stability of more than 60 days. Motivated by these results, the present contribution focuses on the chemical modification which the CH 3NH 3PbI 3– x Cl x perovskite undergoes upon growth of ALD Al 2O 3. Specifically, we combine in situ Infrared (IR) spectroscopy studies during film growth, together with X-ray photoelectron spectroscopy (XPS) analysis of the ALD Al 2O 3/perovskite interface. The IR-active signature of the NH 3 + stretching mode of the perovskite undergoes minimal changes upon exposure to ALD cycles, suggesting no diffusion of ALD precursor and co-reactant (Al(CH 3) 3 and H 2O) into the bulk of the perovskite. However, by analyzing the difference between the IR spectra associated with the Al 2O 3 coated perovskite and the pristine perovskite, respectively, changes occurring at the surface of perovskite are monitored. The abstraction of either NH 3 or CH 3NH 2 from the perovskite surface is observed as deduced by the development of negative N–H bands associated with its stretching and bending modes. The IR investigations are corroborated by XPS study, confirming the abstraction of CH 3NH 2 from the perovskite surface, whereas no oxidation of its inorganic framework is observed within the ALD window process investigated in this work. In parallel, the growth of ALD Al 2O 3 on perovskite is witnessed by the appearance of characteristic IR-active Al–O–Al phonon and (OH)–Al=O stretching modes. Based on the IR and XPS investigations, a plausible growth mechanism of ALD Al 2O 3 on top of perovskite is presented.

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          Most cited references 65

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          Cesium-containing triple cation perovskite solar cells: improved stability, reproducibility and high efficiency† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5ee03874j Click here for additional data file.

          Today's best perovskite solar cells use a mixture of formamidinium and methylammonium as the monovalent cations. Adding cesium improves the compositions greatly.
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            Incorporation of rubidium cations into perovskite solar cells improves photovoltaic performance

            All of the cations currently used in perovskite solar cells abide by the tolerance factor for incorporation into the lattice. We show that the small and oxidation-stable rubidium cation (Rb+) can be embedded into a "cation cascade" to create perovskite materials with excellent material properties. We achieved stabilized efficiencies of up to 21.6% (average value, 20.2%) on small areas (and a stabilized 19.0% on a cell 0.5 square centimeters in area) as well as an electroluminescence of 3.8%. The open-circuit voltage of 1.24 volts at a band gap of 1.63 electron volts leads to a loss in potential of 0.39 volts, versus 0.4 volts for commercial silicon cells. Polymer-coated cells maintained 95% of their initial performance at 85°C for 500 hours under full illumination and maximum power point tracking.
              • Record: found
              • Abstract: not found
              • Article: not found

              Review of recent progress in chemical stability of perovskite solar cells


                Author and article information

                ACS Appl Mater Interfaces
                ACS Appl Mater Interfaces
                ACS Applied Materials & Interfaces
                American Chemical Society
                09 January 2019
                06 February 2019
                : 11
                : 5
                : 5526-5535
                []Department of Applied Physics, Eindhoven University of Technology (TU/e) , P.O. Box 513, 5600 MB Eindhoven, The Netherlands
                []Solliance , High Tech Campus 21, 5656 AE Eindhoven, The Netherlands
                [§ ]Philips Innovation Labs , High Tech Campus 11, 5656 AE Eindhoven, The Netherlands
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                Copyright © 2019 American Chemical Society

                This is an open access article published under a Creative Commons Non-Commercial No Derivative Works (CC-BY-NC-ND) Attribution License, which permits copying and redistribution of the article, and creation of adaptations, all for non-commercial purposes.

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