Hoffmann Institute of Advanced Materials, Shenzhen Polytechnic, 7098 Liuxian Blvd, Nanshan District, Shenzhen 518055, P.R. China.
Dipartimento di Chimica, Università degli Studi di Milano, Milano 20133, Italy.
Inorg Chem. 2022 May 23;61(20):7980-7988. doi: 10.1021/acs.inorgchem.2c00660. Epub 2022 May 9.
Metal-organic frameworks (MOFs) demonstrate strong potential for various important applications due to their well tunable structures and compositions through metal and organic linker engineering. As an effective approach, topology evolution by controlling linker conformation has received considerable attention, where solvents and acids have crucial effects on structural formation. However, a systematic study of such effects remains under investigated. Herein, we carried out a methodical study on the topology evolution in Zr-MOFs directed by solvothermal conditions with various combinations of three common solvents and six different acids. As a result, three Zr-MOFs with different topologies, (HIAM-4007), (HIAM-4008), and (HIAM-4009), were obtained using the same Zr-cluster and tetratopic carboxylate linker, in which structure diversity shows significant influence on their corresponding photoluminescence quantum yields. Further experiments revealed that the acidity of acids and the basicity of solvents strongly influenced the linker conformation in the resultant MOFs, leading to the topology evolution. Such a solvent- and acid-assisted topology evolution represents a general approach that can be used with other tetratopic carboxylate linkers to realize structural diversity. The present work demonstrates an effective structure designing strategy by controlling synthetic conditions, which may prove to be powerful for customized synthesis of MOFs with specific structure and functionality.
金属-有机骨架（MOFs）由于其通过金属和有机连接体工程可进行良好的结构和组成调谐，因此在各种重要应用中表现出强大的潜力。作为一种有效的方法，通过控制连接体构象进行拓扑演变引起了相当大的关注，其中溶剂和酸对结构形成具有关键影响。然而，对这些影响的系统研究仍有待深入探讨。在此，我们通过溶剂热条件对三种常见溶剂和六种不同酸的各种组合指导下的 Zr-MOFs 的拓扑演变进行了系统的研究。结果，使用相同的 Zr 簇和四齿羧酸连接体获得了三种具有不同拓扑结构的 Zr-MOFs，即 （HIAM-4007）、 （HIAM-4008）和 （HIAM-4009），其中结构多样性对其相应的光致发光量子产率有显著影响。进一步的实验表明，酸的酸度和溶剂的碱度强烈影响所得 MOFs 中的连接体构象，从而导致拓扑演变。这种溶剂和酸辅助的拓扑演变代表了一种通用方法，可以与其他四齿羧酸连接体一起使用，以实现结构多样性。本工作通过控制合成条件展示了一种有效的结构设计策略，这可能为具有特定结构和功能的 MOFs 的定制合成提供有力支持。
