Synthesis, Transformation, Catalysis, and Gas Sorption Investigations on the Bismuth Metal–Organic Framework CAU‐17

Abstract

Very few microporous bismuth metal-organic frameworks have been discovered to date. Of these, no detailed experimental characterization of the synthesis and properties have been reported until now for the only one which can be prepared from inexpensive starting materials: CAU-17 [Bi(BTC)(H 2 O)], with H 3 BTC = trimesic acid. In-situ powder X-ray diffraction during solvothermal synthesis of CAU-17 revealed that it crystallizes rapidly within 2 minutes, and if the reaction is not stopped, the MOF transforms into a nonporous dense purely inorganic material within one hour, revealing that CAU-17 is a crystalline intermediate phase. Synthesis scale-up em- [a] 3496 ploying more concentrated reaction mixtures resulted in another Bi trimesate of composition [Bi(HBTC)(NO 3 )(MeOH)]· MeOH, which structurally decomposes upon storage under ambient conditions. Sorption experiments showed that CAU-17 is microporous with a BET surface area of 530 m 2 /g. As a potential greenhouse gas sorbent, CAU-17 showed high SF 6 /N 2 and CO 2 /N 2 selectivity > 31 and 29, respectively. Furthermore, the catalytic activity of CAU-17 was studied in the regioselective ring-opening of styrene oxide by methanol to obtain 2-methoxy-2-phenylethanol, thus demonstrating the existence of coordinatively unsaturated sites in the crystal structure of CAU-17.differ from structure to structure. Also, the large ionic radius of Bi 3+ ions [r (Bi 3+ ) = 1.31 Å, CN = 8] leads to highly complex and irregular coordination geometries around the Bi 3+ cations, which are often influenced by the 6s 2 lone pair of electrons. [18] Characterization of bismuth oxido clusters forming as metastable reaction products is a big challenge, as demonstrated in literature. [19]

MOF-derived Bi2O3@C microrods as negative electrodes for advanced asymmetric supercapacitors

“…22 The second step at 410 C corresponds to the decomposition of framework, leading to Bi 2 O 3 ($33.7 wt%). 23 Consequently, Bi 2 O 3 @C was obtained by thermal treatment in nitrogen atmosphere and the heating temperature was optimized to be 500 C (ESI †). The XRD pattern of ( Fig.…”

Biocompatible, Crystalline, and Amorphous Bismuth-Based Metal–Organic Frameworks for Drug Delivery

“…11,12 The almost infinite possible combinations for designing new MOFs with different chemical properties, topologies, pore sizes and shapes, 8,9,12,13 has allowed an amazing growth in this field, with more than 90,000 different structures reported so far. [14][15][16][17] When proposing MOFs for biomedical applications, they require high biocompatibility and low accumulation in cells. The vast number of MOFs allows one to select optimal building blocks, including metals.…”

Investigation of the Kinetic Stabilization of a Ce4+‐based MOF by in‐situ Powder X‐ray Diffraction

“…Moreover, such techniques can be employed to investigate more complex reactions like the exchange of solvent molecules coordinated to metal ions, the adsorption of guest molecules into flexible frameworks, and the formation of a MOF from a less stable precursor MOF . It was also demonstrated by in‐situ PXRD that MOF themselves can be comparably short‐lived, intermediate precursors which re‐dissolve to eventually form dense compounds , …”

“…[30] It was also demonstrated by in-situ PXRD that MOF themselves can be comparably short-lived, intermediate precursors which re-dissolve to eventually form dense compounds. [31,32] Based on the short reaction times and mild synthesis conditions employed for most Ce 4+ -MOFs, combined with the redox activity of the metal, we suspected that Ce 4+ -MOFs could be actually only kinetically stabilized compounds under typical synthesis conditions. Therefore we herein report the results of an in-situ PXRD survey of the synthesis of the Ce(IV)-MOF [Ce 6 (μ 3 -O) 4 (μ 3 -OH) 4 (PZDC) 4 (OH) 4 (H 2 O) 4 ] denoted as Ce-DUT-67-PZDC.…”