Vapour-phase-transport rearrangement technique for the synthesis of new zeolites

M.S., M.M., R.E.M., J.Č. and M.O. acknowledge OP VVV “Excellent Research Teams” project No.CZ.02.1.01/0.0/0.0/15_003/0000417– CUCAM. M.S. and M.O. thank the Primus Research Program of the Charles University (project number PRIMUS/17/SCI/22 “Soluble zeolites”). R.E.M. also thanks the ERC (Advanced Grant 787073 “ADOR”). A.M. acknowledges The Centre for High-resolution Electron Microscopy (CħEM), supported by SPST of ShanghaiTech University under contract No. EM02161943, and the Natural National Science Foundation of China, through projects NFSC-21850410448 and NSFC- 21835002. Z.L. acknowledges the support from the National Key Research and Development Program of China (2016YFA0300102) and the National Natural Science Foundation of China (11675179, 11434009). J.Č. acknowledges the support of the Czech Science Foundation to the project EXPRO (19-27551×).Owing to the significant difference in the numbers of simulated and experimentally feasible zeolite structures, several alternative strategies have been developed for zeolite synthesis. Despite their rationality and originality, most of these techniques are based on trial-and-error, which makes it difficult to predict the structure of new materials. Assembly-Disassembly-Organization-Reassembly (ADOR) method overcoming this limitation was successfully applied to a limited number of structures with relatively stable crystalline layers ( UTL , UOV , *CTH ). Here, we report a straightforward, vapour-phase-transport strategy for the transformation of IWW zeolite with low-density silica layers connected by labile Ge-rich units into material with new topology. In situ XRD and XANES studies on the mechanism of IWW rearrangement reveal an unusual structural distortion-reconstruction of the framework throughout the process. Therefore, our findings provide a step forward towards engineering nanoporous materials and increasing the number of zeolites available for future applications.Publisher PDFPeer reviewe

Design of zeolite materials with tailored interlayer structure and tunable textural properties

Germanosilicate zeolites attracted a lot of attention during the last decade. The reason for such interest is related to the unique structural properties of germanosilicates, which include zeolites of UTL, UOV, ITH, IWR, IWW, and CIT-13 types. The frameworks of these materials can be described as Si-rich layers connected by double four ring (D4R) units preferentially occupied by Ge atoms. Hydrolytic instability of Ge-O bonds in mentioned frameworks compared with Si-O bonds in conventional zeolites gives the opportunity for controllable chemically selective transformation of the germanosilicate frameworks towards novel types of zeolites including their 2D analogues. This PhD thesis focuses on modification of the structure and textural properties of germanosilicates using different ways of post-synthesis treatment: the ADOR (Assembly - Disassembly - Organization - Reassembly) transformation and post-synthesis degermanation and alumination. Presented work was carried out in the Department of Synthesis and Catalysis at J. Heyrovský Institute of Physical Chemistry in Prague under the supervision of Dr. Maksym Opanasenko and advising of Prof. Jiři Čejka. First way of post-synthesis treatment applied in this work was the recently developed method of zeolite synthesis - the ADOR transformation...

Návrh zeolitických materiálů s řízenou strukturou a texturními vlastnostmi

V posledních deseti letech germanosilikátové zeolity přitahovaly velkou pozornost vědců. Důvodem pro tento zájem jsou jedinečné strukturní vlastnosti germanosilikátů, které zahrnují zeolity UTL, UOV, ITH, IWR, IWW a CIT-13. Struktury těchto materiálů obsahují křemíkové vrstvy spojené jednotkami "double four ring" (D4R), které jsou přednostně obsazeny atomy germania. Hydrolytická nestabilita chemických vazeb Ge-O ve srovnání s vazbami Si-O v zeolitech nabízí možnost kontrolovatelné selektivní transformace germanosilikátů na nové typy zeolitů včetně jejich 2D analogů. Tato disertační práce se zabývá modifikací struktury a texturních vlastností germanosilikátů s použitím různých způsobů postsyntetické modifikace: ADOR (Assembly - Disassembly - Organization - Reassembly) přeměnou a postsyntetickou degermanací a aluminací. Práce byla vypracována na Oddělení syntézy a katalýzy Ústavu fyzikální chemie J. Heyrovského AV ČR, v.v.i. pod vedením Dr. Maksyma Opanasenka a prof. Jiřího Čejky. První metodou postsyntetické úpravy materiálů byla v této práci syntéza zeolitů pomocí ADOR přeměny. Studium germanosilikátů UOV, CIT-13 a IWR, které obsahují D4R jednotky bohaté na germanium umožnilo rozšířit skupinu IPC materiálů o 3 nové zeolity (IPC-12, IPC-13 a IPC-17) a potvrdit univerzálnost této techniky. Struktura...Germanosilicate zeolites attracted a lot of attention during the last decade. The reason for such interest is related to the unique structural properties of germanosilicates, which include zeolites of UTL, UOV, ITH, IWR, IWW, and CIT-13 types. The frameworks of these materials can be described as Si-rich layers connected by double four ring (D4R) units preferentially occupied by Ge atoms. Hydrolytic instability of Ge-O bonds in mentioned frameworks compared with Si-O bonds in conventional zeolites gives the opportunity for controllable chemically selective transformation of the germanosilicate frameworks towards novel types of zeolites including their 2D analogues. This PhD thesis focuses on modification of the structure and textural properties of germanosilicates using different ways of post-synthesis treatment: the ADOR (Assembly - Disassembly - Organization - Reassembly) transformation and post-synthesis degermanation and alumination. Presented work was carried out in the Department of Synthesis and Catalysis at J. Heyrovský Institute of Physical Chemistry in Prague under the supervision of Dr. Maksym Opanasenko and advising of Prof. Jiři Čejka. First way of post-synthesis treatment applied in this work was the recently developed method of zeolite synthesis - the ADOR transformation....Katedra fyzikální a makromol. chemieDepartment of Physical and Macromolecular ChemistryPřírodovědecká fakultaFaculty of Scienc

Insight into the ADOR zeolite-to-zeolite transformation:the UOV case

IPC-12 zeolite is the first member of the ADOR family produced by the structural transformation of UOV. The details of the UOV rearrangement were studied to determine the influence of the properties of the parent zeolite and treatment conditions on the outcome of IPC-12 formation. It was established that incomplete disassembly of UOV can be caused by insufficient lability of interlayer connectivity in the parent material possessing Si-enriched D4Rs or by inhibition of hydrolysis by diluted acid at high temperature. The impacts of specific interactions of the framework with anions on controllable breaking of interlayer connectivity and the conditions of the treatment at low pH (&lt;-1) on the characteristics of the produced IPC-12 were found to be negligible. The concentration of the acid significantly influences the extent and even the direction of UOV transformation. Layer disassembly is inhibited in 1-4 M acid solutions, and complete hydrolysis to a layered precursor can be achieved in 0.1 M solution, while application of 12 M solution led to direct formation of IPC-12. Layer reassembly followed using in situ XRD measurement with a synchrotron source was found to be a gradual process starting at 40 °C and completing at 200-220 °C.</p

ADOR zeolite with 12 × 8 × 8-ring pores derived from IWR germanosilicate

R. E. M. and P. S. W. thank the ERC for the provision of an Advanced Grant (ADOR 787073).Zeolites have been well known for decades as catalytic materials and adsorbents and are traditionally prepared using the bottom-up synthesis method. Although it was productive for more than 250 zeolite frameworks, the conventional solvothermal synthesis approach provided limited control over the structural characteristics of the formed materials. In turn, the discovery and development of the Assembly-Disassembly-Organization-Reassembly (ADOR) strategy for the regioselective manipulation of germanosilicates enabled the synthesis of previously unattainable zeolites with predefined structures. To date, the family tree of ADOR materials has included the topological branches of UTL, UOV, IWW, *CTH, and IWV zeolites. Herein, we report on the expansion of ADOR zeolites with a new branch related to the IWR topology, which is yet unattainable experimentally but theoretically predicted as highly promising adsorbents for CO2 separation applications. The optimization of not only the chemical composition but also the dimensions of the crystalline domain in the parent IWR zeolite in the Assembly step was found to be the key to the success of its ADOR transformation into previously unknown IPC-17 zeolite with an intersecting 12 × 8 × 8-ring pore system. The structure of the as-prepared IPC-17 zeolite was verified by a combination of microscopic and diffraction techniques, while the results on the epichlorohydrin ring-opening with alcohols of variable sizes proved the molecular sieving ability of IPC-17 with potential application in heterogeneous catalysis. The proposed synthesis strategy may facilitate the discovery of zeolite materials that are difficult or yet impossible to achieve using a traditional bottom-up synthesis approach.Publisher PDFPeer reviewe

Formation and structure of ZIF-8@PEO coating on the surface of zinc

Recently, plasma electrolytic oxidation (PEO) found broad application as a multi-purpose process to create effective corrosion and wear resistant coatings on various metallic substrates. The exceptional properties of metal organic frameworks (MOFs) put them also in focus as perspective materials for corrosion protection. In this work, the formation of a novel ZIF-8@PEO coating is reported for the first time. It was synthesized by controllable recrystallization of a PEO layer formed on zinc alloy Z1 into ZIF-8 in the presence of 2-methylimidazole organic linkers. The multi-stage mechanism of PEO to ZIF-8 rearrangement is proposed. Cross section, glow discharge optical emission spectroscopy and nano-focused synchrotron X-ray diffraction demonstrated that varying of synthesis parameters, the ZIF-8@PEO coating with different distribution of ZIF-8 through PEO layer can be prepared. Based on the results of laser scanning microscopy, the surface smoothing was observed with increasing the degree of the PEO-to-ZIF-8 rearrangement. Containing two components, the novel ZIF-8@PEO coating is expected to combine admirable physical-chemical properties of both PEO and ZIF-8. Such a feature can open the way for its potential application not only for corrosion protection, but also for photo- and heterogeneous catalysis

Magneto-structural correlations of novel kagomé-type metal organic frameworks

Here, we report the in situ formation of two novel metal organic frameworks based on copper and cobalt using tetrazole-5-carboxylate ethyl ester as the ligand synthesized by a hydrothermal route. Both MOFs show isostructural three-dimensional networks with kagomé tilling topology and show high chemical stability. Despite the iso-structural nature, both systems show distinct magnetic features. For the Cu-based kag-MOF system, the co-existence of energetically competing ferromagnetic and antiferromagnetic interactions resulted in the establishment of a long-range ferromagnetic order sustainable up to 52 K. On the contrary, dominant antiferromagnetic interactions identified in the Co-based MOF material were responsible for an antiferromagnetic order evolving below 7 K. Importantly, chemically different metallic ions gave rise to distinct magnetic ordering with different strength and temperature-sustainability. No dynamic magnetic phenomena were observed, implying that the concentration of the metal ions within the structure exceeded the percolation limit favoring the formation of the long-range magnetic order in the studied systems. Both designed kagomé-type MOFs were thus found to show a coexistence of high frustration and long range magnetic ordering with limited orbital quenching, resulting from the choice of the ligands and crystal arrangement. Thus, the results demonstrated the potentiality to effectively control and alter the magnetic features within the particular kagomé-type MOF lattice due to the chemical nature and structural incorporation of individual metal ions. The presented approach offers a promising strategy to further fine tune the physical characteristics of the MOF-based systems equipping them with more competitive potential and extending their application portfolio to other fields

Data underpinning "Expansion of the ADOR strategy for the synthesis of new zeolites: The synthesis of IPC-12 from zeolite UOV"

The data files are not yet publicly available. Enquiries and requests for data should be directed to the publication's corresponding authors: Kasneryk, V, Shamzhy, M, Opanasenko, M, Wheatley, PS, Morris, SA, Russell, SE, Mayoral, A, Trachta, M, Čejka, J & Morris, RE 2017, 'Expansion of the ADOR strategy for the synthesis of new zeolites: the synthesis of IPC-12 from zeolite UOV' Angewandte Chemie, vol. 56, no. 15, pp. 4324-4327. DOI: 10.1002/anie.20170059