Shaw Bikash Kumar, Hughes Ashlea R, Ducamp Maxime, Moss Stephen, Debnath Anup, Sapnik Adam F, Thorne Michael F, McHugh Lauren N, Pugliese Andrea, Keeble Dean S, Chater Philip, Bermudez-Garcia Juan M, Moya Xavier, Saha Shyamal K, Keen David A, Coudert François-Xavier, Blanc Frédéric, Bennett Thomas D
Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK.
Department of Chemistry, University of Liverpool, Liverpool, UK.
Nat Chem. 2021 Aug;13(8):778-785. doi: 10.1038/s41557-021-00681-7. Epub 2021 May 10.
Several organic-inorganic hybrid materials from the metal-organic framework (MOF) family have been shown to form stable liquids at high temperatures. Quenching then results in the formation of melt-quenched MOF glasses that retain the three-dimensional coordination bonding of the crystalline phase. These hybrid glasses have intriguing properties and could find practical applications, yet the melt-quench phenomenon has so far remained limited to a few MOF structures. Here we turn to hybrid organic-inorganic perovskites-which occupy a prominent position within materials chemistry owing to their functional properties such as ion transport, photoconductivity, ferroelectricity and multiferroicity-and show that a series of dicyanamide-based hybrid organic-inorganic perovskites undergo melting. Our combined experimental-computational approach demonstrates that, on quenching, they form glasses that largely retain their solid-state inorganic-organic connectivity. The resulting materials show very low thermal conductivities (~0.2 W m K), moderate electrical conductivities (10-10 S m) and polymer-like thermomechanical properties.
金属有机框架(MOF)家族中的几种有机-无机杂化材料已被证明在高温下能形成稳定的液体。骤冷会导致形成熔融淬火的MOF玻璃,其保留了晶相的三维配位键。这些杂化玻璃具有引人入胜的特性,可能会有实际应用,但到目前为止,熔融淬火现象仍仅限于少数MOF结构。在这里,我们转向有机-无机杂化钙钛矿——由于其离子传输、光电导、铁电和多铁性等功能特性,在材料化学中占据突出地位——并表明一系列基于双氰胺的有机-无机杂化钙钛矿会发生熔化。我们结合实验和计算的方法表明,在淬火时,它们会形成玻璃,在很大程度上保留其固态无机-有机连接性。所得材料显示出非常低的热导率(约0.2 W m⁻¹ K⁻¹)、适度的电导率(10⁻¹⁰ S m⁻¹)和类似聚合物的热机械性能。