Thermally activated structural phase transitions and processes in metal–organic frameworks

Journal article

The field of metal–organic frameworks (MOFs) has rapidly evolved from disconnected examples of multi-dimensional coordination polymers into an expansive collection of functional materials containing over 100,000 structures. Because any material’s chemical structure dictates its function, a robust structural understanding is a crucial prerequisite for the optimization of a material’s physical properties and its effective deployment towards an application. This is especially true for MOFs, which frequently demonstrate multiple possible structures from a single metal-ligand combination. Without proper identification, these phase distributions confuse analysis and hinder applicability of the material(s). Conversely, when well-understood, phase multiplicity serves to increase the number of available structures (and functions) within an established chemical window. Thus, control over phase distributions in MOF systems is a critical aspect of their analysis and utility.In this work, a luminescent ligand based on the tetraphenylethene (TPE) molecule is used as a foundation to generate three distinct MOF systems, which are analyzed for their essential structures and functional properties. All three TPE-based systems are found to demonstrate various degrees of phase multiplicity; while some distributions depend solely on the initial synthetic conditions to generate distinct framework isomers, others undergo dynamic and reversible phase transformations according to their post-synthetic treatments. These structural aspects are characterized in detail, and mechanistic explanations are presented that can be applied to broad design principles towards phase-controlled MOF systems

Authors: Castillo-Blas, C; Chester, AM; Keen, DA; Bennett, TD

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society of Chemistry
• Journal: Chemical Society Reviews
• Volume: 53
• Issue: 7
• Pages: 3606-3629
• Publication date: 2024-04-02
• DOI: 10.1039/d3cs01105d
• EISSN: 1460-4744
• ISSN: 0306-0012
• Language: English
• Keywords: Chemistry; Biochemical engineering; Nanotechnology; Phase (matter); Materials science; Adsorption; Metal-organic framework; Engineering; Organic chemistry