(335g) Controlled Synthesis of Bimetallic MOFs Using Pre-Programed Hydroxy Double Salt Precursors: From Conversion Mechanism to Membrane Applications

Bimetallic metal-organic frameworks (MOFs) possess mixed metal nodes that could boost the adsorption and catalytic performance via synergistic effects. However, precise control over the metal ratios in bimetallic MOFs is difficult by direct mixing the MOF reagents in conventional solvothermal synthesis, due to the mismatch of reaction kinetics between the two types of metal precursors and the organic linker. We developed a unique strategy to synthesize bimetallic MOFs using pre-programed hydroxy double salt (HDS) precursors. We obtained ZIF-7, ZIF-8, ZIF-65 and ZIF-71 with controlled ratio of Co and Zn nodes. We further employed combined in-situ synchrotron X-ray diffraction and X-ray absorption spectroscopy to study the dynamic conversion from the HDS precursor to bimetallic MOFs. In addition, we will discuss how we applied this synthesis to fabricate thin films for membrane separation applications. Our bimetallic MOF thin films are also promising for other integrated forms such as chemical sensors and decontamination filters.

References:

[1] M. Zhang, X. Luo, Y. Hu, Y. Shen, Y. Chen, S. Yuan, H. Wang, X. Xing, J. Zhao*. Deciphering Metal–Organic Framework Synthesis from Hydroxy Double Salts: In-Situ Insights via Synchrotron X-ray Diffraction and Absorption Spectroscopy. Chem & Bio Engineering, 2024, in press. DOI: 10.1021/cbe.3c00078

[2] Y. Chen, S. Yuan, Y. Li, Y. Ma, C. Zhang, Q. Mao, Y. Luo, J. Zhao*. Pre-Programed Hydroxy Double Salt Templates for Room-Temperature Controlled Synthesis of Mixed-Metal Zeolitic Imidazolate Frameworks. J. Mater. Chem. A, 2021, 9, 18557-18563.