Mechanochemical Synthesis of Sn(II) and Sn(IV) Iodide Perovskites and Study of Their Structural, Chemical, Thermal, Optical, and Electrical Properties. Issue 4 (14th August 2019)

• Record Type: Journal Article
• Authors: El Ajjouri, Yousra; Locardi, Federico; Gélvez-Rueda, María C.; Prato, Mirko; Sessolo, Michele; Ferretti, Maurizio; Grozema, Ferdinand C.; Palazon, Francisco; Bolink, Henk J.
• Other Names: Mhaisalkar Subodh G. guestEditor.; Mathews Nripan guestEditor.; Bolink Henk J. guestEditor.; Bahulayan Damodaran guestEditor.
• Is Part Of: Energy technology. Volume 8:Issue 4(2020:Apr.)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-08-14
• Subjects: low-bandgap -- mechanochemistry -- perovskites -- solid-state -- tin; Energy development -- Periodicals; Power resources -- Periodicals; 333.79
• DOI: 10.1002/ente.201900788
• Languages: English
• ISSNs: 2194-4288

Abstract

Abstract : Phase‐pure CsSnI3, FASnI3, Cs(PbSn)I3, FA(PbSn)I3 perovskites (FA = formamidinium = HC(NH2 )2 + ) as well as the analogous so‐called vacancy‐ordered double perovskites Cs2 SnI6 and FA2 SnI6 are mechanochemically synthesized. The addition of SnF2 is found to be crucial for the synthesis of Cs‐containing perovskites but unnecessary for hybrid ones. All compounds show an absorption onset in the near‐infrared (NIR) region, which makes them especially relevant for photovoltaic applications. The addition of Pb(II) and SnF2 is crucial to improve the electronic properties in 3D Sn(II)‐based perovskites, in particular their charge carriers mobility (≈0.2 cm 2 Vs −1 ) which is enhanced upon reduction of the dark carrier conductivity. Stokes‐shifted photoluminescence is observed on dry powders of Sn(II)‐based perovskites, which makes these materials promising for light‐emitting and sensing applications. Thermal stability of all compounds is examined, revealing no significant degradation up to at least 200 °C. This meets the requirements for standard operation conditions of most optoelectronic devices and is potentially compatible with thermal vacuum deposition of polycrystalline thin films. Abstract : Dry mechanochemical synthesis of various Sn(II) and Sn(IV) iodide perovskites is reported. As‐prepared materials show excellent phase purity as determined by X‐ray diffraction as well as tunable bandgap and photoluminescencence in the near‐infrared. Hence, mechanochemistry appears as an ideal route to develop low‐toxicity materials for optoelectronics in a solvent‐free approach.