Stabilized High-Membered and Phase-Pure 2D All Inorganic Ruddlesden–Popper Halide Perovskites Nanocrystals as Photocatalysts for the CO2 Reduction Reaction

Lin C.-CLi J.-YShe N.-ZHuang S.-KHuang C.-YWang I.-TTsai F.-LWei C.-YLee T.-YWang D.-YWen C.-YLi S.-SYabushita ALuo C.-WChen C.-CCHUN-WEI CHEN2022-11-162022-11-16202216136810https://www.scopus.com/inward/record.uri?eid=2-s2.0-85128062775&doi=10.1002%2fsmll.202107881&partnerID=40&md5=6cf56bade184bcbef3380338c6ccb4c1https://scholars.lib.ntu.edu.tw/handle/123456789/625442In contrast to the 2D organic-inorganic hybrid Ruddlesden–Popper halide perovskites (RPP), a new class of 2D all inorganic RPP (IRPP) has been recently proposed by substituting the organic spacers with an optimal inorganic alternative of cesium cations (Cs+). Nevertheless, the synthesis of high-membered 2D IRPPs (n > 1) has been a very challenging task because the Cs+ need to act as both spacers and A-site cations simultaneously. This work presents the successful synthesis of stable phase-pure high-membered 2D IRPPs of Csn+1PbnBr3n+1 nanosheets (NSs) with n = 3 and 4 by employing the strategy of using additional strong binding bidentate ligands. The structures of the 2D IRPPs (n = 3 and 4) NSs are confirmed by powder X-ray diffraction and high-resolution aberration-corrected scanning transmission electron microscope measurements. These 2D IRPPs NSs exhibit a strong quantum confinement effect with tunable absorption and emission in the visible light range by varying their n values, attributed to their inherent 2D quantum-well structure. The superior structural and optical stability of the phase-pure high-membered 2D IRPPs make them a promising candidate as photocatalysts in CO2 reduction reactions with outstanding photocatalytic performance and long-term stability. © 2022 Wiley-VCH GmbH.2D all-inorganic perovskites; CO 2 reduction; high-membered perovskites; quantum well structure; Ruddlesden–Popper phases[SDGs]SDG7[SDGs]SDG13Carbon dioxide; Chelation; Lead compounds; Ligands; Niobium compounds; organic-inorganic materials; Positive ions; Semiconductor quantum wells; Transmission electron microscopy; 2d all-inorganic perovskite; CO 2 reduction; Halide perovskites; High-membered perovskite; Inorganics; Phase pure; Quantum well structures; Reduction reaction; Ruddlesden-Popper; Ruddlesden-Popper phase; PerovskiteStabilized High-Membered and Phase-Pure 2D All Inorganic Ruddlesden–Popper Halide Perovskites Nanocrystals as Photocatalysts for the CO2 Reduction Reactionjournal article10.1002/smll.202107881354170592-s2.0-85128062775