Change search
Link to record
Permanent link

Direct link
Publications (10 of 76) Show all publications
Ikonnikova, E., Cho, J., Zou, X., Sutrisno, A., Burton, A. W., Pham, T. & Willhammar, T. (2026). Low-Dimensional Zeotypes Templated by Stacked Cyclic Benzimidazolium Revealed by Electron Crystallography. Journal of the American Chemical Society, 148(6), 6686-6694
Open this publication in new window or tab >>Low-Dimensional Zeotypes Templated by Stacked Cyclic Benzimidazolium Revealed by Electron Crystallography
Show others...
2026 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 148, no 6, p. 6686-6694Article in journal (Refereed) Published
Abstract [en]

The structural diversity of zeolites depends strongly on the use of organic structure-directing agents (OSDAs) that guide their formation. Low-dimensional zeolitic materials, such as layered or chain-like phases, can serve as key intermediates in topotactic condensation pathways, yet the mechanisms governing their formation and transformation remain poorly understood. Here, we report three low-dimensional zeolitic materials, EMM-75P, EM-L01, and EM-L02, synthesized using benzimidazolium cations as OSDAs. Their structures were determined by three-dimensional electron diffraction (3D ED), including the atomic structure of the OSDAs, revealing their confinement within the framework to shed light on their structure-directing role. The bulky benzimidazolium OSDAs prevent the formation of materials with three-dimensional framework structures and instead direct the formation of low-dimensional zeotypes. Upon calcination, the two-dimensional layered aluminosilicate zeotype EMM-75P undergoes topotactic condensation to form a three-dimensional zeolite, EMM-75, with a previously unreported zeolite framework topology. Aluminosilicate EM-L01 is a 2D analogue of STF/SFF zeolite frameworks and partially condensed to an STF-topology upon calcination, whereas EM-L02, a 1D silicate composed of double 6-ring chains, packed analogous to the CHA zeolite framework, collapses during the thermal treatment. The detailed structural characterization of these three materials provides insights into the mechanism of topotactic condensation and demonstrates how such pathways can lead to new zeolite materials.

National Category
Materials Chemistry Inorganic Chemistry
Identifiers
urn:nbn:se:su:diva-253061 (URN)10.1021/jacs.5c22569 (DOI)001681278200001 ()41641818 (PubMedID)2-s2.0-105030510002 (Scopus ID)
Available from: 2026-03-09 Created: 2026-03-09 Last updated: 2026-04-24Bibliographically approved
Smalley, C. J. .., Hughes, C. E., Willhammar, T., Pandya, R., Saikin, S. K., Johnstone, D. N., . . . Collins, S. M. (2026). Structural properties, polymorphism, and multiscale disorder unravel energy transport limitations in perylene diimide semiconductors. Science Advances, 12(22), Article ID eaed0037.
Open this publication in new window or tab >>Structural properties, polymorphism, and multiscale disorder unravel energy transport limitations in perylene diimide semiconductors
Show others...
2026 (English)In: Science Advances, ISSN 2375-2548., Vol. 12, no 22, article id eaed0037Article in journal (Refereed) Published
Abstract [en]

Organic semiconductors continue to make substantial performance gains from photovoltaics to electronics. However, understanding how differences in solid-state structure give rise to large differences in energy transport properties remains unresolved. We report that microcrystals of two perylene diimide (PDI) derivatives differing only in their terminal groups [cyclohexyl (CH) and 4-heptyl (ST)] have exciton diffusion coefficients differing by more than two orders of magnitude. Applying state-of-the-art techniques for microcrystal structure determination, we report the crystal structures of CH-PDI and two polymorphs of ST-PDI. Scanning electron diffraction reveals a range of crystallographic defects in ST-PDI microcrystals, attributed to polymorph intergrowths, while electron energy loss spectroscopy links these defects to nanoscale electronic structure changes. Computational modeling demonstrates that rotational disorder explains the difference in exciton diffusion coefficients. Our observations establish the importance of defect-induced orientational disorder as a source of extrinsic energetic disorder, highlighting the need for defect management in organic semiconductor technologies.

National Category
Condensed Matter Physics Materials Chemistry
Identifiers
urn:nbn:se:su:diva-257432 (URN)10.1126/sciadv.aed0037 (DOI)001778139300004 ()42202018 (PubMedID)2-s2.0-105040631813 (Scopus ID)
Available from: 2026-06-29 Created: 2026-06-29 Last updated: 2026-06-29Bibliographically approved
Svensson Grape, E., Willhammar, T. & Inge, A. K. (2025). Brilliantly Red: The Structure of Carmine. Crystal Growth & Design, 25(12), 4100-4105
Open this publication in new window or tab >>Brilliantly Red: The Structure of Carmine
2025 (English)In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 25, no 12, p. 4100-4105Article in journal (Refereed) Published
Abstract [en]

Carmine is a red pigment made from dried cochineal, a scale insect that has been a source of brilliant scarlet reds in clothing and art for more than two millennia, with records dating back to 700 BC. Since the 16th century, it has been intensely traded all over the world and was one of the most important trade goods for the Spanish empire at its economic peak. Despite still being used on an industrial scale, with hundreds of metric tonnes produced annually, the exact molecular and crystal structures of the dyestuff remains undetermined. Notably, both modern-day commercial carmine and pigments prepared following historical recipes show strikingly similar diffraction patterns, indicating a common crystalline structure. Here we show that the crystal structure of carmine can, at last, be determined using three-dimensional electron diffraction measurements, revealing a tetranuclear complex that assembles into a nanoporous supramolecular structure with pore diameters of approximately 1.8 nm, held together by intermolecular hydrogen bonding. Our results establish a definite structure of carmine, unveiling a surprisingly complicated arrangement in a long-used commodity with economic and cultural impact, while also highlighting the serendipitous creation of a man-made supramolecular material that dates back hundreds if not thousands of years.

National Category
Materials Chemistry
Identifiers
urn:nbn:se:su:diva-244393 (URN)10.1021/acs.cgd.5c00185 (DOI)001507105300001 ()2-s2.0-105007500658 (Scopus ID)
Available from: 2025-06-17 Created: 2025-06-17 Last updated: 2025-09-12Bibliographically approved
Wegner, L., Morelli Venturi, D., Ikonnikova, E., Hetze, K., Theissen, J., Derveaux, E., . . . Stock, N. (2025). CAU-63, an Ultramicroporous Al-MOF with a Honeycomb-Shaped 2D IBU. Inorganic Chemistry, 64(40), 20254-20261
Open this publication in new window or tab >>CAU-63, an Ultramicroporous Al-MOF with a Honeycomb-Shaped 2D IBU
Show others...
2025 (English)In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 64, no 40, p. 20254-20261Article in journal (Refereed) Published
Abstract [en]

The hydrothermal synthesis of the new aluminum metal-organic framework (Al-MOF) CAU-63 [Al7(OH)12O3(2,4-HPydc)3] and two new Al coordination polymers (CPs) Al-Pydc-CP1 [Al2(OH)5(2,4-HPydc)] and Al-Pydc-CP2 [Al(OH)(H2O)(2,4-Pydc)] linked by anions of lutidinic acid (pyridine-2,4-dicarboxylic acid, 2,4-H2Pydc) is reported. High-throughput investigations of the Al3+/2,4-H2Pydc/NaOH/H2O system were carried out to determine the fields of formation. An increase of the molar ratio of metal to linker was found to be the key parameter for the formation of higher condensed inorganic building units (IBU), changing from dimeric to one- and two-dimensional structures. The crystal structures were determined by 3D electron diffraction with subsequent Rietveld refinement against powder X-ray diffraction data. The pyridine nitrogen atoms of the linker molecules coordinate to aluminum ions in all three compounds, resulting in crystal structures deviating from the typically observed MIL-53 and CAU-10 type frameworks. The coordination polymers Al-Pydc-CP1 and Al-Pydc-CP2 contain edge-sharing Al–O/N polyhedra leading to dimeric and helical IBUs, while in CAU-63, tetrameric [Al4O14N2] units are bridged by Al3+ ions, leading to a honeycomb Al–O–N network with organic moieties interconnecting the layers. This linkage results in channel-like ultramicropores, which are accessible to H2O and NH3 molecules but too small to adsorb N2 and even CO2.

National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:su:diva-248283 (URN)10.1021/acs.inorgchem.5c03315 (DOI)001585993500001 ()41037797 (PubMedID)2-s2.0-105018573205 (Scopus ID)
Available from: 2025-10-21 Created: 2025-10-21 Last updated: 2025-10-21Bibliographically approved
Nero, M., Carlsen, M., Liebi, M. & Willhammar, T. (2025). Chiral Hierarchies at the Nanoscale Revealed by Three-Dimensional Scanning Electron Diffraction. ACS Nano, 19(40), 35777-35786
Open this publication in new window or tab >>Chiral Hierarchies at the Nanoscale Revealed by Three-Dimensional Scanning Electron Diffraction
2025 (English)In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 19, no 40, p. 35777-35786Article in journal (Refereed) Published
Abstract [en]

Natural biocomposites such as wood and plant cell walls exhibit prominent mechanical properties largely attributed to the nanoscale organization of fibrous components, such as cellulose, which often adopt chiral arrangements. However, resolving the three-dimensional (3D) arrangement of these structures at the nanoscale remains a significant challenge, particularly in beam-sensitive materials. This study introduces a method for 3D reconstruction of orientation based on scanning electron diffraction (SED), enabling the quantitative mapping of chiral supramolecular organization with sub-100 nm spatial resolution. By acquiring low-dose SED data at multiple tilt angles and applying a symmetry-based reconstruction algorithm, we resolved the 3D orientation of cellulose fibrils in native oat husk and birch wood. Our results reveal a multilayered cell wall architecture with alternating helical handedness, providing precise measurements of 3D fibril orientation. This method reveals complex hierarchical structures at the nanoscale, enabling rapid data acquisition and analysis using widely available instrumentation. The ability to resolve such chiral organization provides insights into material properties as well as opportunities for designing bioinspired materials with tunable mechanical and functional properties that extend far beyond natural biocomposite materials.

Keywords
scanning electron diffraction, chirality, cellulose, 3D reconstruction, electron diffraction
National Category
Materials Chemistry
Research subject
Materials Chemistry
Identifiers
urn:nbn:se:su:diva-246782 (URN)10.1021/acsnano.5c12291 (DOI)001585276000001 ()41027111 (PubMedID)2-s2.0-105018668157 (Scopus ID)
Available from: 2025-09-10 Created: 2025-09-10 Last updated: 2025-11-17Bibliographically approved
Rincon, I., Salles, F., Jimenez-Duro, M., Svensson Grape, E., Willhammar, T., Inge, A. K., . . . Horcajada, P. (2025). Effective removal of thiabendazole pesticide from polluted water using metal–organic frameworks. Applied water science, 15(12), Article ID 315.
Open this publication in new window or tab >>Effective removal of thiabendazole pesticide from polluted water using metal–organic frameworks
Show others...
2025 (English)In: Applied water science, ISSN 2190-5487, E-ISSN 2190-5495, Vol. 15, no 12, article id 315Article in journal (Refereed) Published
Abstract [en]

Pesticides have become a common environmental pollutant in bodies of water in recent decades, negatively affecting the aquatic ecosystems along with their living organisms. In this regard, thiabendazole (TBZ) has emerged as one of the most detected pesticides in wastewater due to its widespread application in agriculture. Despite its toxicological effects and persistence, no technology is currently available for its efficient removal. Recent adsorption strategies using eco-friendly porous materials have emerged as an effective, low-cost, and easy-to-operate alternative for water pollutant removal. Among them, metal–organic frameworks (MOFs) were selected here as attractive adsorbents due to their outstanding water stability and a priori, compatible pore sizes with the TBZ molecule. Upon screening of 8 MOFs with different natures and structures, the most promising material was the microporous bismuth(III)-ellagate SU-101, with remarkable removal efficiencies (89% in just 5 min). The material was successfully shaped into micrometric pellets and packed into a column for its suitable implementation in a continuous flow device, simulating a real decontamination environment by using pollutant-doped tap water. This SU-101 column was able to efficiently eliminate TBZ during 4.6 consecutive days, with the absence of significant MOF degradation (< 1.5%), and was successfully regenerated (88%) preserving functionality over 2 cycles. These resulting outcomes pave the way for further SU-101 implementation in real decontamination processes.

Keywords
Continuous-flow, Metal–organic frameworks, MOF-shaping, Thiabendazole, Water decontamination
National Category
Materials Chemistry Environmental Sciences
Identifiers
urn:nbn:se:su:diva-250881 (URN)10.1007/s13201-025-02587-y (DOI)001626973700001 ()2-s2.0-105023310471 (Scopus ID)
Available from: 2026-01-12 Created: 2026-01-12 Last updated: 2026-01-12Bibliographically approved
Chen, H., Garemark, J., Li, L., Nero, M., Ritter, M., Cheung, O., . . . Berglund, L. A. (2025). Green Nanotechnology of Cell Wall Swelling for Nanostructured Transparent Wood of High Optical Performance. Small, 21(5), Article ID 2406749.
Open this publication in new window or tab >>Green Nanotechnology of Cell Wall Swelling for Nanostructured Transparent Wood of High Optical Performance
Show others...
2025 (English)In: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 21, no 5, article id 2406749Article in journal (Refereed) Published
Abstract [en]

Transparent wood composites provide new functionalities through active additives distributed at the nanoscale. Scalable nanotechnology includes processing where nanoparticles and molecules are brought into the dense wood cell wall. A novel cell wall swelling step through green chemistry is therefore investigated. Sub-zero centigrade NaOH treatment provides extensive cell wall swelling. Cell wall accessibility is vastly increased so that chemicals can readily impregnate the nanostructured cell wall. Transparent wood with a thickness of up to 15 mm can therefore be fabricated. The optical transmittance and the attenuation coefficient are improved since the polymer is distributed inside the cell wall as a matrix for the nanoscale cellulose fibrils. The proposed technology paves the way for scalable wood nanoengineering.

Keywords
accessibility, cell wall swelling, large-scale wood delignification, sub-zero NaOH treatment, transparent wood composites
National Category
Polymer Technologies
Identifiers
urn:nbn:se:su:diva-239855 (URN)10.1002/smll.202406749 (DOI)001378999600001 ()39690791 (PubMedID)2-s2.0-85212286332 (Scopus ID)
Available from: 2025-02-26 Created: 2025-02-26 Last updated: 2025-09-10Bibliographically approved
Schmithorst, M. B., Ikonnikova, E., Cruz Delgado, B. L., McNarney, A., Stoev, A., Zeng, L., . . . Chmelka, B. F. (2025). Origins of the Hydrothermal Stability of Cu-Chabazite Zeolites for the Selective Catalytic Reduction of NOx. Journal of the American Chemical Society, 147(50), 46152-46162
Open this publication in new window or tab >>Origins of the Hydrothermal Stability of Cu-Chabazite Zeolites for the Selective Catalytic Reduction of NOx
Show others...
2025 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 147, no 50, p. 46152-46162Article in journal (Refereed) Published
Abstract [en]

Cu-exchanged chabazite zeolites are used industrially as catalysts for abatement of NOx pollution from diesel engines; however, catalyst activity is adversely impacted by exposure to high temperature steam. This occurs due to both dealumination of the zeolite framework and aggregation of Cu2+ cations into larger oxide agglomerates that are less active. Under oxidation-limited conditions in the presence of coadsorbed NH3, hydrothermal aging of Cu-chabazite leads to a surprising increase in the rate of NOx reduction per redox-active Cu cation at low temperatures (200 °C). A combination of electron microscopy, electron diffraction, NMR spectroscopy, and reaction kinetics analyses reveals that, although a portion of Cu species sinter into large agglomerates during aging, activity is maintained by the remaining Cu2+ cations that are stabilized by pairs of framework aluminum sites. These sites exhibit lower activation enthalpies for ammonia exchange dynamics, manifesting enhanced mobility of Cu2+ ions that persist as the extent of aging increases. The results yield insights into the complicated physicochemical processes and ramifications associated with deactivation of technologically important Cu-CHA zeolite catalysts, including the dynamics of adsorbed intermediates and the macroscopic reaction properties of the selective catalytic reduction of NOx over active Cu species.

National Category
Catalytic Processes
Identifiers
urn:nbn:se:su:diva-251432 (URN)10.1021/jacs.5c14587 (DOI)001631976600001 ()41346281 (PubMedID)2-s2.0-105025148645 (Scopus ID)
Funder
Swedish Research Council, 2019-00815Swedish Research Council, 2019-05465
Available from: 2026-01-22 Created: 2026-01-22 Last updated: 2026-05-28Bibliographically approved
Bohigues, B., Rojas-Buzo, S., Salusso, D., Xia, Y., Corma, A., Bordiga, S., . . . Serna, P. (2025). Overcoming activity/stability tradeoffs in CO oxidation catalysis by Pt/CeO2. Nature Communications, 16, Article ID 7451.
Open this publication in new window or tab >>Overcoming activity/stability tradeoffs in CO oxidation catalysis by Pt/CeO2
Show others...
2025 (English)In: Nature Communications, E-ISSN 2041-1723, Vol. 16, article id 7451Article in journal (Refereed) Published
Abstract [en]

The use of redox active metal oxides to support noble metals is critical in the design of highly-active CO oxidation catalysts for gas emissions control. Unfortunately, supports promoting the activity, such as CeO2, tend also to promote acute catalyst deactivation by turning highly-active metallic Pt clusters into less-active PtOx species, under practical reaction conditions (high-temperature and/or the excess of O2). This leads to a problematic activity/stability tradeoff where Pt/CeO2 catalysts, highly-active, and Pt on non-reducible supports, highly stable, are bookends. Herein, we report a method to trap Pt at V-shaped pockets/stepped sites of CeO2 that break this undesired correlation by showing both high activity and stability in the CO oxidation reaction. XAS, CO-DRIFT, XPS, HAADF-STEM, and DFT are used to infer that the generation of low order metallic Pt clusters connected to two crystallographic planes of the support is key to inhibit (deactivating) re-oxidation paths of the metal, as a result of the high-energy required to form disordered/distorted PtOx ensembles at these positions. This new material allows, thus, to operate outside the commonly observed, limiting, activity/stability tradeoff.

National Category
Catalytic Processes
Identifiers
urn:nbn:se:su:diva-246631 (URN)10.1038/s41467-025-62726-6 (DOI)001550678500026 ()40796774 (PubMedID)2-s2.0-105013030397 (Scopus ID)
Available from: 2025-09-12 Created: 2025-09-12 Last updated: 2025-09-12Bibliographically approved
Lu, P., Xu, J., Sun, Y., Guillet-Nicolas, R., Willhammar, T., Fahda, M., . . . Valtchev, V. (2024). A stable zeolite with atomically ordered and interconnected mesopore channel. Nature, 636(8042), 368-373
Open this publication in new window or tab >>A stable zeolite with atomically ordered and interconnected mesopore channel
Show others...
2024 (English)In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 636, no 8042, p. 368-373Article in journal (Refereed) Published
Abstract [en]

Zeolites are crystalline microporous materials constructed by corner-sharing tetrahedra (SiO4 and AlO4), with many industrial applications as ion exchangers, adsorbents and heterogeneous catalysts. However, the presence of micropores impedes the use of zeolites in areas dealing with bulky substrates. Introducing extrinsic mesopores, that is, intercrystal/intracrystal mesopores, in zeolites is a solution to overcome the diffusion barrier. Still, those extrinsic mesopores are generally disordered and non-uniform; moreover, acidity and crystallinity are always, to some extent, impaired. Thus, synthesizing thermally stable zeolites with intrinsic mesopores that are of uniform size and crystallographically connected with micropores, denoted here as intrinsic mesoporous zeolite, is highly desired but still not achieved. Here we report ZMQ-1 (Zeolitic Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, no. 1), an aluminosilicate zeolite with an intersecting intrinsic meso-microporous channel system delimited by 28 × 10 × 10-rings, in which the 28-ring has a free diameter of 22.76 Å × 11.83 Å, which reaches the mesopore domain. ZMQ-1 has high thermal and hydrothermal stability with tunable framework Si/Al molar ratios. ZMQ-1 is the first aluminosilicate zeolite with an intrinsic meso-microporous channel system. The Brønsted acidity of ZMQ-1 imparts high activity and unique selectivity in the catalytic cracking of heavy oil. The position of the organic structure-directing agent (OSDA) used for ZMQ-1 synthesis was determined from three-dimensional electron diffraction (3D ED) data, which shows the unique structure-directing role of the OSDA in the formation of the intrinsic meso-microporous zeolite. This provides an incentive for preparing other stable mesopore-containing zeolites.

National Category
Materials Chemistry
Identifiers
urn:nbn:se:su:diva-240554 (URN)10.1038/s41586-024-08206-1 (DOI)001397120900026 ()39663489 (PubMedID)2-s2.0-85211643707 (Scopus ID)
Available from: 2025-03-10 Created: 2025-03-10 Last updated: 2025-04-01Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-6120-1218

Search in DiVA

Show all publications