Solution‐Based Synthesis Routes for the Preparation of Noncentrosymmetric 0‐D Oxide Nanocrystals with Perovskite and Nonperovskite Structures

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 18; no. 30; pp. e2200992 - n/a
• Main Authors: Dantelle, Géraldine, Beauquis, Sandrine, Le Dantec, Ronan, Monnier, Virginie, Galez, Christine, Mugnier, Yannick
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.07.2022; Wiley-VCH Verlag
• Subjects: Barium titanates; Chemical composition; Chemical Sciences; Crystal structure; Crystallinity; Crystallization; Electronic devices; Ferroelectricity; Lithium niobates; Material chemistry; Miniaturization; multifunctional nanocrystals; Nanocrystals; Nanotechnology; noncentrosymmetric oxides; Nonlinear optics; nucleation/growth mechanisms; Optical properties; Perovskites; Piezoelectricity; Potassium titanyl orthophosphate; Shape effects; Sol-gel processes; solution‐based synthesis; noncentrosymmetric oxides; multifunctional nanocrystals; nucleation/growth mechanisms; solution-based synthesis; nucleation/ growth mechanisms
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202200992

With the miniaturization of electronic‐based devices, the foreseen potential of new optical nanoprobes and the assessment of eventual size and shape effects, elaboration of multifunctional noncentrosymmetric nanocrystals with ferroelectric, pyroelectric, piezoelectric, and nonlinear optical properties are the subject of an increasing research interest. Here, the recent achievements from the solution‐based methods (coprecipitation in homogeneous and nanostructured media, sol‐gel processes including various chemistries and hydro/solvothermal techniques) to prepare 0‐D perovskite and nonperovskite oxides in the 5–500 nm size range are critically reviewed. To cover a representative list of covalent‐ and ionic‐type materials, BaTiO3 and its derivatives, niobate compounds (i.e., K/Na/LiNbO3), multiferroic BiFeO3, and crystals of lower symmetry including KTiOPO4 and some iodate compounds such as Fe(IO3)3 and La(IO3)3 are systematically in focus. The resulting size, morphology, and aggregation state are discussed in light of the proposed formation mechanisms. Because of a higher complexity related to their chemical composition and crystalline structures, improving the rational design of these multifunctional oxides in terms of finely‐tuned compositions, crystalline hosts and structure–property relationships still need in the future a special attention of the research community to the detailed understanding of the reaction pathways and crystallization mechanisms. Solution‐based methods are reviewed for the preparation of representative, multifunctional noncentrosymmetric oxide nanocrystals with perovskite and nonperovskite crystalline structures. Elucidation of the reaction pathways and crystallization mechanisms is a prerequisite for improving their resulting morphology in the future and aggregation state for the development of advanced applications. The main concepts and possible new directions are given in the outlook section.