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Item type:Publication, Access status: with files , Multimodal synchrotron X-ray analysis of palm-leaf manuscripts: structural and compositional signatures of botanical genus, manufacture, and provenance(Springer, 2026-10-06); ; ; ; Palm-leaf manuscripts are cultural artifacts from South and Southeast Asia, yet diverse preparation methods and degradation histories complicate material characterization and comparison. We use a multimodal synchrotron approach combining small- and wide-angle X-ray scattering with X-ray fluorescence to extract structural and compositional descriptors from unprocessed leaves, writing supports, and manuscripts. Supervised learning evaluates differences related to genus, processing stage, and geographical origin. The processing stage is classified reliably, whereas genus separation is clearer in processed materials than in unprocessed leaves. Origin classification shows partial separability, with distinct regional profiles and overlaps reflecting shared preparation traditions, class imbalance, and botanical and degradation-related factors. Classification relies on multivariate combinations of crystallinity, fibril orientation, and elemental descriptors. This scalable, non-destructive framework supports comparison of collections and investigation of material similarities among traditions. The classifications represent comparative material profiles rather than definitive provenance assignments and must be combined with codicological and historical evidence.Publicationtype: Journal Article23 10 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Distinct electrification regimes at solid–liquid interfaces revealed by water isotope substitution(American Chemical Society (ACS), 2026-07-28); ; ; ; Solid–liquid contact electrification is widely studied using diverse experimental geometries that are often implicitly assumed to probe equivalent interfacial processes. Here, we directly test this assumption by comparing immersion–emersion, droplet-based contact, and pressure-driven intrusion–extrusion electrification using the same hydrophobic nanoporous silicon monolith and isotopically substituted liquids (H2O and D2O). Despite identical surface chemistry, isotopic substitution produces qualitatively different electrical responses depending on the wetting regime. Immersion–emersion experiments show polarity inversion between H2O and D2O, while droplet measurements reveal distinct charge evolution and periodic opposite-polarity events. In contrast, forced nanopore intrusion preserves polarity but strongly enhances electrical output for D2O. These results demonstrate that wetting of surface nanoroughness during droplet, vs immersion–emersion, vs complete nanopores wetting upon intrusion–extrusion correspond to fundamentally different electrification states. By using isotope substitution as a controlled probe, this work establishes a general framework for disentangling protocol-dependent effects in solid–liquid contact electrification and triboelectric energy conversion.Publicationtype: Journal Article10 15 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Open metal sites govern hydration kinetics and molecular fluctuations in metal–organic frameworks(American Chemical Society (ACS), 2026-07-01); ; ; ; Water under nanoscale confinement exhibits structural and dynamical states distinct from bulk behavior, yet the role of pore chemistry in governing these states remains insufficiently understood. Herein, the hydration kinetics and molecular-scale fluctuations of water confined within a comprehensive series of MOF-74 metal-organic frameworks incorporating Mg, Ni, Co, and mixed-metal compositions were investigated and compared with those observed in mesoporous MCM-41 silica. In situ impedance pectroscopy resolves a pronounced multistep hydration mechanism in MOF-74, initiated by rapid coordinative binding at open metal sites, followed by cluster formation and final capillary condensation. In contrast to MCM-41 silica, where capillary condensation dominates, the presence of coordinatively unsaturated metal centers fundamentally alters adsorption pathways. Mixedmetal MOF-74 exhibits accelerated and temporally broadened hydration, reflecting heterogeneous distributions of adsorption energies. Broadband dielectric spectroscopy reveals a distinct water-specific relaxation process (w-relaxation) attributed to fluctuations of water clusters interacting with metal nodes. Relaxation rates follow Arrhenius behavior with activation energies increasing in the order Mg < Ni < Co and further enhanced in mixed-metal systems. Remarkably, water confined within MOF-74 remains liquid-like down to 133 K without crystallization, whereas crystallization is observed in MCM-41 silica. All activation data of the MOF-74 systems obey a common Meyer−Neldel compensation relation, indicating cooperative molecular dynamics and suggesting a hindered glass-transition−like process of confined water clusters. These findings demonstrate that open metal sites and metal composition enable programmable control over hydration kinetics and collective water dynamics in microporous frameworks. MOF-74 thus provides a tunable model platform for engineering water-driven transport, catalysis, and energy-relevant processes at the nanoscale.Publicationtype: Journal Article48 50 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Decoupling geometry and surface chemistry in 3D-printed ALD-functionalized porous ceramic channels(American Chemical Society (ACS), 2026-06-29); ; ; Minna, FortuneCapillary-driven transport is traditionally attributed to the static pore geometry and wettability. However, the time-dependent surface energy of metal oxides, amplified by the high surface area of porous media, remains a key yet underexplored aspect. This study introduces a novel manufacturing route capable of decoupling macroscopic geometry from surface chemistry by integrating additive manufacturing combined with colloidal assembly (AMCA) and functionalization by atomic layer deposition (ALD). This approach enables the fabrication of highly porous aluminum(III) oxide (Al2O3) and titanium dioxide (TiO2) ceramic channels after thermal burn-out. Within these structures, the structural and chemical properties are tuned and investigated. Spontaneous imbibition experiments at 0, 6, and 24 h after burn-out reveal a transition from a classical Lucas−Washburn rise to a resistance-limited regime dominated by evaporation and viscous drag. Time-resolved contact-angle measurements revealed that both oxides become superhydrophilic after burn-out and undergo subsequent hydrophobic recovery. Despite TiO2 being intrinsically more hydrophilic, Al2O3 channels consistently exhibited faster imbibition rates and a higher liquid rise. This behavior is attributed to the rapid surface relaxation of Al2O3, which reduces contact-line friction and minimizes pinning at high-energy adsorption sites, thereby enhancing fluid uptake. Macroscopic geometrical variations in printed channels did not affect the imbibition height but scaled linearly with imbibed volume, confirming the successful decoupling of geometric and chemical transport factors. The excellent structural reproducibility of the AMCA-ALD method establishes it as a robust manufacturing platform for programmable capillary transport. This approach provides a general pathway to design porous ceramics with independently engineered geometries and surface chemistries for applications in microfluidics, diagnostics, and catalysis.Publicationtype: Journal Article29 52 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , All-water supercapacitor enabled by 1-nm clay channels(Nature Publishing Group UK, 2026-06-05); ; ; 59 96 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Directional dark field for nanoscale full-field transmission X-ray microscopyDark-field X-ray imaging visualizes structural inhomogeneities through small-angle scattering, but existing directional methods are confined to the micrometer scale. While recent advances have extended dark-field capabilities to nanoscale transmission X-ray microscopy, directional scattering retrieval - critical for characterizing anisotropic nanostructures - has remained inaccessible for imaging resolutions in the sub-micrometer scale. Here, we demonstrate the first directional dark-field setup for nanoimaging, achieving orientation mapping of scattering features below the spatial resolution limit. Our method is experimentally simple to implement with existing transmission X-ray microscopy setups. We validate its performance by successfully resolving sub-resolution test structure orientations, cross-correlating orientational changes within hierarchical nanoporous materials, and mapping the directional arrangement of hydroxyapatite nanocrystals 30 - 70 nm within human tooth enamel. By utilizing shadow regions in the optical configuration, we further extend the detectable scattering vector range, demonstrating a pathway toward size-selective dark-field imaging. This advancement enables the quantitative structural characterization of anisotropic nanomaterials, which are critical to biomineralization, advanced materials, and nanotechnology applications.Publicationtype: Journal Article45 46 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Combined effects of salt and microplastics on evaporation and crystallization dynamics in porous media(American Chemical Society (ACS), 2026-03-18); ; ; ; This study investigates the combined effects of salinity and microplastic contamination on the evaporation process and salt crystallization in porous media through complementary column- and pore-scale experiments. Laboratory soil columns were packed with either pure sand or sand mixed with 5% (w/w) poly(vinyl chloride) (PVC) microplastics and subsequently saturated with freshwater or saline (NaCl) solution. Evaporation and crystallization dynamics were monitored by using mass loss measurements, surface optical and thermal imaging, and synchrotron X-ray tomography. Results show that salinity consistently suppressed evaporation by roughly 25–30%, whereas PVC microplastics enhanced it, generating substantial differences in cumulative water loss across treatments. Moreover, thermal imaging revealed distinct surface responses: NaCl samples developed salt crusts that progressively reduced local temperature contrasts and led to more spatially uniform surface conditions, whereas PVC-NaCl samples exhibited lower mean surface temperatures but substantially higher spatial variability, reflected in larger and more persistent temperature anomalies during drying. Pore-scale μCT imaging further confirmed that microplastics altered crystallization patterns by redistributing salt deposition over the upper part of the sand profile and modifying the nucleation behavior. Together, these findings underscore the complex interplay between microplastics and salinity, with implications for soil moisture regulation, surface energy flux, and environmental monitoring strategies.Publicationtype: Journal Article31 61 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Engineered self-assembly of plasmonic gold nanoparticles into two-dimensional and three-dimensional arrays within the pores of porous silicon membranes(Wiley, 2026-02-07); ; ; ; We report a facile centrifugation-based method for assembling polystyrene (PSSH)-functionalized gold nanoparticles (Au NPs) onto porous silicon (pSi) substrates in two distinct configurations: two- and three-dimensional (2D and 3D) assemblies. The 2D assemblies are densely packed monolayer coatings of the exposed Si-surfaces including the inner pore walls, whereas the 3D structures result from Au NPs clustering inside the pores. Remarkably, this shift from 2D to 3D architectures was achieved by minor modification of the PSSH coating thickness. Scanning electron microscopy (SEM) characterization confirmed the homogeneity and high packing density of these assemblies extending over several thousand square micrometers. This approach offers a straightforward and versatile route for the fabrication of well-ordered pSi–Au NP hybrid nanostructures with potential applications in catalysis, surface-enhanced spectroscopy and optical metamaterials.Publicationtype: Journal Article44 73 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Salt complexation drives liquid crystalline self-assembly in crown ether–amino acid hybrids(Royal Society of Chemistry (RSC), 2026-02-06); ; Crown ether–amino acid hybrids represent a promising class of amphiphilic molecules combining ion recognition with self-assembly capabilities. Despite extensive studies on their binding properties, the influence of inorganic salt complexation on their liquid crystalline behaviour remains underexplored. Here we synthesized amphiphilic [18]-crown-6 derivatives of l-dihydroxyphenylalanine and tetrahydroisoquinoline analogues, systematically investigating the effects of alkyl chain length and salt type on mesophase formation. Complexation with various salts induced liquid crystalline phases, transitioning from smectic A to columnar hexagonal structures as anion size and alkyl chain length increased. Structural analyses and electron density mapping revealed assembly into charged superdiscs forming columnar stacks with tunable ion channels. Broadband dielectric spectroscopy highlighted differences in molecular mobility and conductivity linked to molecular design. These findings establish salt complexation as a key strategy to control self-assembly and ion transport in crown ether–amino acid hybrids, advancing their potential in responsive soft materials and ion-conductive applications.Publicationtype: Journal Article11 9 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Triboelectrification during non-wetting liquids intrusion–extrusion in hydrophobic nanoporous silicon monoliths(Elsevier, 2025-12-15); ; ; ; Triboelectric nanogenerators (TENGs) have emerged as promising devices for converting mechanical energy into electrical energy through contact electrification and electrostatic induction. However, the generated energy, unlike instantaneous power, current and voltage, is rarely addressed in the vibrant research field of TENGs. In this study, we investigate Intrusion–Extrusion Triboelectric Nanogenerators (IE-TENGs) based on nanoporous silicon monoliths and non-wetting liquids (i.e., water and a 1 mg/mL polyethylenimine solution), addressing the energy generated during this process, conversion efficiency as well as the mechanism underlying the observed phenomena. Compared to powder-based IE-TENGs, the use of monolithic silicon structures enables more efficient and reproducible energy harvesting, with significant improvements in both instantaneous power density and energy per cycle. We also analyzed the impact of compression rate and liquid properties on electrical output, showing that higher compression rates improve power generation, while modifying the liquid medium significantly improves conversion efficiency, reaching up to 9 %. Furthermore, through computational analysis, we identify the crucial role of grafting defects on the generated triboelectric output. This work introduces a novel approach to triboelectric energy harvesting by implementing a monolithic nanoporous architecture and offering an alternative pathway for enhancing contact electrification via confined solid–liquid interfaces. These findings provide new insights into the triboelectric behavior of porous systems and pave the way for next-generation high-performance IE-TENGs, with potential applications in wearable electronics, environmental energy harvesting, and self-powered sensing systems.Publicationtype: Journal Article38 72