{"title":"Mechanistic insights for (alkyl)methacrylate-based cationic hybrid gels reinforced with sepiolite, montmorillonite, mica, bentonite and kaolin: A comparative thermodynamic study with all-in-one formulations","authors":"Beril Tanc Kaya , Rabia Bozbay , Nermin Orakdogen","doi":"10.1016/j.clay.2025.108016","DOIUrl":"10.1016/j.clay.2025.108016","url":null,"abstract":"<div><div>A series of clay-based cationic hybrids from <em>N</em>,<em>N</em>-dimethylaminoethyl methacrylate and 2-acrylamido-2-methyl-1-propanesulfonic acid in the presence of various clays; montmorillonite (Mt), bentonite (Bnt), sepiolite (Sep), kaolin and mica was prepared by in-situ free-radical polymerization. The primary objective was to understand the macroscale properties of ionically modified (alkyl)methacrylate-based polymers reinforced with nanometer-sized clays. Water absorption, repeated on-off switching in salt solutions, elasticity and efficiency in removal of anionic indigo carmine (IC) dye, widely used in textile industry for denim production, were comparatively analyzed depending on the clay type. Compared to Sep and Mt-integrated hybrids, the mechanical property was weaker due to the inhomogeneous distribution in the structure, while the mica and kaolin-integrated gels were resistant to high compression. Mt- and Sep-addition increased the swelling by four-fold, while the swelling in the presence of mica was limited. Hybrids exhibited good salt resistance and pH-sensitive swelling, with largest change in the volume being observed in Mt-doped gels, while least change was in Kaolin-doped ones. Based on the effect of salinity, the swelling of hybrids in aqueous solutions of monovalent and divalent metal nitrates followed the decreasing order as KNO<sub>3</sub> > NaNO<sub>3</sub> > Ba(NO<sub>3</sub>)<sub>2</sub>. Regardless of clay type, hybrid cryogels prepared at low polymerization temperature followed Fickian diffusion, while at higher temperatures, the clay type altered the mechanism and non-Fickian diffusion was observed in hybrid hydrogels doped with Mt, kaolin and mica. Anionic IC adsorption, which reached equilibrium in 30 min, varied between 93.4 % and 97.6 %. The presence of Kaolin and Bnt caused a significant increase in adsorption, while a decrease was observed in presence of Sep. Adsorption isotherms determined by three parameter models were compared with two-parameter models in linear and non-linear fitting of equilibrium data; Freundlich isotherm model and pseudo-first order kinetic model had the best fitness. Comparative results demonstrated that clay-integrated (alkyl)methacrylate-based cationic hybrids can be employed as effective and economical adsorbents for removal of anionic dyes from aqueous environments.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"279 ","pages":"Article 108016"},"PeriodicalIF":5.8,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145327140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impact of the functionalized clay on the poly(lactic acid)/polybutylene adipate terephthalate (PLA/PBAT) based biodegradable nanocomposites: Thermal and rheological properties","authors":"Mariia Kostenko , Yurij Stetsyshyn , Khrystyna Harhay , Yuriy Melnyk , Volodymyr Donchak , Semen Khomyak , Oleksandr Ivanukh , Milan Kracalik","doi":"10.1016/j.clay.2025.108020","DOIUrl":"10.1016/j.clay.2025.108020","url":null,"abstract":"<div><div>PLA/PBAT-based (Ecovio) nanocomposites were prepared using both pristine and functionalized clays, including PBMA- and PBA-grafted brushes, which were selected for their surface energy compatibility with the PLA phase. XRD analysis confirmed the successful intercalation of clay and good dispersion within the polymer matrix. Thermal analysis revealed the typical two-step degradation pattern (PLA followed by PBAT), with APTES-functionalized clays lowering the peak degradation temperature of PLA to 305 °C. In comparison, PBA-grafted clays increased it to 329 °C compared to 322 °C for neat Ecovio. The addition of nanoclays to Ecovio-based composites did not significantly affect the overall crystallinity of the system. Thermomechanical and FTIR analyses indicated that APTES promoted polymer degradation during processing, whereas PBA grafting helped mitigate these effects. Rheological measurements revealed increased melt elasticity in Ecovio nanocomposites containing PBA-grafted clays without compromising processability, a key advantage for compostable film applications in packaging. Overall, the inclusion of PBA-grafted clays improved both the compatibility and thermal stability of PLA/PBAT-based nanocomposites. Moreover, this work introduces, for the first time, a straightforward strategy for tuning the properties of multi-tonnage industrial composites such as Ecovio, providing a practical approach to enhance performance while preserving compostability.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108020"},"PeriodicalIF":5.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fabrication of multifunctional hydrophobic silica aerogels with superior thermal safety enabled by a dual flame-retardant strategy","authors":"Miao Liu, Yuanyuan Yang, Zhi Li, Yumin Duan, Zikang Chen, Jiahui Chen, Xiaoxu Wu","doi":"10.1016/j.clay.2025.108021","DOIUrl":"10.1016/j.clay.2025.108021","url":null,"abstract":"<div><div>Hydrophobic silica aerogel (HSA) represents a promising thermal insulating material for addressing challenges from climate change and energy consumption. However, its susceptibility to high-temperature sintering and flammability limits its application scope. Herein, a thermal safety regulation strategy was proposed through hypophosphorous acid catalysis and the incorporation of flame-retardant modified halloysite nanotubes. The resulting HSA composite exhibited improved fire resistance, with 16.6 % and 15.5 % reductions in peak of heat release rate and total heat release, respectively. Additionally, after prolonged thermal attack at 800 °C, the skeleton structure of the aerogel remained stable, showing no collapse. Furthermore, the enhancement of the thermal safety of the aerogel did not decrease the hydrophobicity (water contact angle of 142.9°) and heat insulation properties (thermal conductivity of 22.4 mW/m·K). This study provides valuable insights into optimizing the thermal safety of HSA, which broaden its applications in thermal insulation with fire protection requirements.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108021"},"PeriodicalIF":5.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carolina Vega Verduga , Jeffrey D. Henderson , Mark S. Workentin
{"title":"Clickable halloysite nanotubes for interfacial strain promoted azide-alkyne cycloaddition of Au25 nanoclusters","authors":"Carolina Vega Verduga , Jeffrey D. Henderson , Mark S. Workentin","doi":"10.1016/j.clay.2025.108013","DOIUrl":"10.1016/j.clay.2025.108013","url":null,"abstract":"<div><div>Halloysite nanotubes (HNT) are naturally occurring biocompatible tubular clay minerals, susceptible to functionalization because of their inherent siloxane, silanol and aluminol functionality, that has made them attractive nanomaterials for modification and further applications. Interfacial strained promoted alkyne-azide cycloaddition (I-SPAAC) is a well-known click reaction that can be used to generate new hybrid HNT based nanomaterials. Herein, both azide and bicyclononyne strained alkyne modified HNT are prepared enabling I-SPAAC reactions with suitable reaction partners. I-SPAAC was demonstrated on both and was used to covalently bond azide-modified [N(C<sub>8</sub>H<sub>17</sub>)<sub>4</sub>][Au<sub>25</sub>(SCH<sub>2</sub>CH<sub>2</sub>-C<sub>6</sub>H<sub>4</sub>-N<sub>3</sub>)<sub>18</sub>] (Au<sub>25</sub>) nanoclusters to HNT without need for catalyst and without nanocluster core alterations. Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) confirmed HNT functionalization and that the Au<sub>25</sub> nanocluster was covalently bound to HNT through analysis of N 1s high resolution XPS spectra. Transmission electron microscopy (TEM) with EDX confirmed that gold nanoclusters are homogeneously distributed over HNT. Diffuse reflectance spectra displayed Au<sub>25</sub> HOMO-LUMO transitions indicative that the metal core of the nanocluster remains unaltered. The successful covalent bonding of modified HNT capable of I-SPAAC enables the delivering of function to these solid supports for future applications, including nanohybrid gold nanoclusters for use in solid state reactions or heterogeneous catalysis.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108013"},"PeriodicalIF":5.8,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Soil particle size and Hofmeister effects on soil colloidal aggregation","authors":"Linqiao Yu, Aizhou He, Hang Li","doi":"10.1016/j.clay.2025.108018","DOIUrl":"10.1016/j.clay.2025.108018","url":null,"abstract":"<div><div>Soil aggregates play a vital role in maintaining soil structure. In this study, soil colloid particles (<2000 nm) were further divided into three size fractions (<500 nm, 500–1000 nm, and 1000–2000 nm) to investigate the coupled effects of particle size and cation specificity (Li<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>, Cs<sup>+</sup>) on soil colloid aggregation. The results showed: (1) For each size fraction, the aggregation rate and critical coagulation concentration (CCC) exhibited consistent ion-specific effects that was originated from the asymmetric hybridization of cation outer electron orbitals. (2) Among all size fractions, <500 nm soil colloid particles showed the fastest aggregation rate and required the lowest electrolyte concentration for rapid aggregation, while 1000–2000 nm particles not only had the slowest aggregation rate but also completely failed to achieve rapid aggregation. Although <500 nm colloid particles carried the highest charge quantity, their large specific surface area resulted in the lowest actual surface charge density and weakest interparticle electrostatic repulsion. Moreover, the Brownian motion of <500 nm particles was nearly 100 times that of 1000–2000 nm particles. (3) The main clay mineral affecting charge quantity and specific surface area across different size fractions was montmorillonite, <500 nm particles contained the highest montmorillonite content. Based on these findings, three key conclusions are drawn: (1) <500 nm particles play a crucial role in overall soil particle aggregation, as their rapid Brownian motion enables active collisions with >1000 nm particles, driving collective particle coagulation. (2) Effective soil aggregation occurs exclusively when <500 nm particles interact with cations exhibiting asymmetric outer electron orbital hybridization. (3) For constant-charge soil, montmorillonite-type clay minerals serve as essential material foundations promoting soil particle aggregation.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108018"},"PeriodicalIF":5.8,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ahmed Ben Ali , Saeed Al-Meer , Mustafa S. Nasser , Ibnelwaleed A. Hussein
{"title":"Microwave-synthesized composite preformed particle gels based on tragacanth gum and palygorskite for high-salinity high-temperature conditions","authors":"Ahmed Ben Ali , Saeed Al-Meer , Mustafa S. Nasser , Ibnelwaleed A. Hussein","doi":"10.1016/j.clay.2025.108006","DOIUrl":"10.1016/j.clay.2025.108006","url":null,"abstract":"<div><div>Preformed particle gels (PPGs) emerged as promising materials for water management in mature oil reservoirs, particularly in heterogeneous carbonate formations characterized by high-permeability zones and fractures. In this study, hybrid composite PPGs were synthesized using tragacanth gum (TG), a biodegradable polysaccharide, grafted with acrylamide (AM) and crosslinked with <em>N</em>, <em>N</em>′-methylene bisacrylamide (MBA) in the presence of palygorskite (Pal) clay sourced from Qatar's Midra Shale. A microwave-assisted free-radical polymerization technique facilitated the rapid formation of gel particles with well-integrated organic-inorganic networks. Comprehensive characterization using XRD, XRF, FTIR, SEM, and TGA confirmed Pal's successful grafting, thermal reinforcement, and morphological integration into the PPG matrix. Swelling behavior in real Gulf seawater (TDS = 45,2 mg/L) and rheological measurements taken at elevated temperatures (80 °C and 100 °C) showed that the addition of Pal enhanced gel rigidity but slightly reduced swelling capacity, likely due to increased steric hindrance. The formulation TPAC<sub>2</sub> (2.5 g Pal) exhibited an optimal balance between swelling (14.2 g/g at 100 °C) and mechanical strength, making it a strong candidate for reservoir applications. These findings highlighted the potential of TG–Pal composite gels as environmentally friendly, thermally stable PPGs suitable for high-salinity, high-temperature conditions.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108006"},"PeriodicalIF":5.8,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Raphaela de Oliveira , Yara Galvão Gobato , Ronei C. de Oliveira , José R. de Toledo , Verônica C. Teixeira , Angelo Malachias , Cesar R. Rabahi , Chunwei Hsu , Adilson J.A. de Oliveira , Herre S.J. van der Zant , Ingrid D. Barcelos , Alisson R. Cadore
{"title":"Correlative analysis of iron-driven structural, optical, and magnetic properties in natural biotite crystals","authors":"Raphaela de Oliveira , Yara Galvão Gobato , Ronei C. de Oliveira , José R. de Toledo , Verônica C. Teixeira , Angelo Malachias , Cesar R. Rabahi , Chunwei Hsu , Adilson J.A. de Oliveira , Herre S.J. van der Zant , Ingrid D. Barcelos , Alisson R. Cadore","doi":"10.1016/j.clay.2025.108012","DOIUrl":"10.1016/j.clay.2025.108012","url":null,"abstract":"<div><div>Biotite crystals are phyllosilicate trioctahedral micas with the general chemical formula K(Mg,Fe)<sub>3</sub>AlSi<sub>3</sub>O<sub>10</sub>(OH)<sub>2</sub> that form a solid-solution series with iron-poor phlogopite and iron-rich annite endmembers. With a wide band gap energy and a layered structure with free surface charges, biotite nanosheets can be readily obtained by cleavage methods and used as dielectrics in nanodevice fabrication for the next generation of electronics and energy harvesting. Here, a comprehensive study of biotite samples with different iron concentrations and oxidation states is presented. Structural, optical, magneto-optical, and magnetic characterizations were performed using several experimental techniques, including state-of-the-art synchrotron-based techniques, to correlate the iron chemistry (content and oxidation state) with the macroscopic properties of both minerals. The study reveals a nanoscale-homogeneous Fe distribution via synchrotron X-ray fluorescence mapping, defect-mediated optical transitions modulated by Fe<sup>3+</sup>/Fe<sup>2+</sup> ratios, and temperature-dependent magnetic transitions from paramagnetism to competing ferro−/antiferromagnetic interactions. Furthermore, the use of these biotite crystals as substrates for ultrathin heterostructures incorporating monolayer (ML) MoSe<sub>2</sub> is explored by magneto photoluminescence at cryogenic temperatures. The results show that the presence of iron impurities in different oxidation states significantly impacts the valley properties for ML-MoSe<sub>2</sub>. Overall, these findings offer a comprehensive interpretation of the physical properties of bulk biotites in a correlative approach, serving as a robust reference for future studies aiming to explore biotites in their ultrathin form.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108012"},"PeriodicalIF":5.8,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Topochemical silanization of the Aurivillius phase Bi2SrTa2O9 and post-synthesis complexation","authors":"Pacôme Chapel , Thibaud Henry , Frédéric Payet , Cédric Leuvrey , Fabrice Leroux , Nathalie Parizel , Pierre Rabu , Guillaume Rogez","doi":"10.1016/j.clay.2025.108017","DOIUrl":"10.1016/j.clay.2025.108017","url":null,"abstract":"<div><div>Functionalization of layered oxides to convey a reactive function prone to coordinate metal cations in-between the inorganic layers is a challenge with respect the potential reactivity of the oxides with these groups. Here, silanization by amine-bearing alkoxysilanes was proposed as a convenient way to bring in free amine groups in the interlayer space. Yet, silanization in itself has seldom been explored for layered oxides.</div><div>This study presents a microwave-assisted multistep approach for functionalizing the Aurivillius Bi<sub>2</sub>SrTa<sub>2</sub>O<sub>9</sub> phase by organosilanes. Three different organosilanes were inserted in the interlayer space, triethoxyoctylsilane, 3-(aminopropyl)triethoxysilane and N-[3(trimethyoxysilyl)propyl]ethylenediamine. The synthetic pathway described here constitutes a fast and efficient approach to silanize the interlayer space of layered perovskites, while preserving the layered structure. The compounds were fully characterized, notably by X-Ray Diffraction (XRD) and solid state Nuclear Magnetic Resonance (NMR), which demonstrated that the organosilanes were effectively grafted onto the oxide layers, forming stable Si-O-Ta bonds, and allowed to precise the grafting scheme, evidencing the very limited formation of siloxane network. Using this approach, free amino groups were introduced in-between the inorganic oxide layers due to the preferential reactivity of the oxide sheets with the alkoxysilane groups compared to amine. These amino groups are available for further coordination by transition metal ions using a post-synthesis complexation reaction. As a proof of concept their complexation ability towards Cu<sup>2+</sup> ions was demonstrated by UltraViolet-Visible (UV–Vis) and Electron Paramagnetic Resonance (EPR) spectroscopies.</div><div>This soft chemistry strategy constitutes a new versatile, fast and efficient method to introduce transition metal cations into layered oxides and paves the way for the design and synthesis of complex architectures, specifically designed for application, in catalysis, sensors, metal cation remediation or luminescence for instance.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108017"},"PeriodicalIF":5.8,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zheng Chen , Tao Su , Jingwen Tang , Chaofan Yi , Jing Li , Shuai Zhang , Kaixuan Song
{"title":"The mutual interaction between geopolymerization and hydration in producing aluminosilicate geopolymer-OPC composites: Interface characterizations and mix-design regulation","authors":"Zheng Chen , Tao Su , Jingwen Tang , Chaofan Yi , Jing Li , Shuai Zhang , Kaixuan Song","doi":"10.1016/j.clay.2025.108014","DOIUrl":"10.1016/j.clay.2025.108014","url":null,"abstract":"<div><div>Aiming to meet the demand for carbon peak and neutrality, the combination of alkali-activated metakaolin (AAMK) and Ordinary Portland cement (OPC) presents a promising solution. However, the lack of a comprehensive understanding of their synergistic effects poses challenges for the mix-design of geopolymer-OPC composites. This study investigated the macro-mechanical properties and microstructural characteristics of metakaolin-based geopolymer-OPC composites with varying compositional oxide ratios. The results demonstrate that adjusting the SiO₂/Al₂O₃ and H₂O/Na₂O ratios significantly affected the compressive strength alongside the initiation of plastic deformation. In contrast, the Na₂O/Al₂O₃ ratio modulated both the elastic modulus and the transition from elastic to plastic behaviour. Microstructural analysis reveals that the above oxide ratios may differentially influence the polycondensation of N-A-S-H at the interface compared to the geopolymer matrix alone, owing to the migration of mineral compounds and the variation of flowability at fresh state. Optimal compressive strength, surpassing that of pure OPC systems, was achieved at SiO₂/Al₂O₃ = 3.2, Na₂O/Al₂O₃ = 0.8–1.0, and H₂O/Na₂O = 8.75–10.75, highlighting the potential of these composites to reduce cement usage and carbon emissions in construction applications.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108014"},"PeriodicalIF":5.8,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Changhui Song , Jinchong Gan , Jing Zou , Man Mo , Zhijie Fang , Haitao Wang
{"title":"Ab initio calculations of the structural, electronic and mechanical properties of palygorskite under high pressure","authors":"Changhui Song , Jinchong Gan , Jing Zou , Man Mo , Zhijie Fang , Haitao Wang","doi":"10.1016/j.clay.2025.108010","DOIUrl":"10.1016/j.clay.2025.108010","url":null,"abstract":"<div><div>To further expand the applications of palygorskite (Pal) in materials science, this research employs density functional theory (DFT) to systematically investigate the alterations of its structural, electronic and mechanical properties under high pressure. This finding reveal that the Mg<img>O bonds, particularly those associated with ring oxygen atoms, undergo significant contraction under high pressure, which is indicative of the high compressibility of Pal. Meanwhile, the volume of Pal decreases substantially within the pressure interval of 10–20 GPa. Moreover, at 20 GPa, the band gap of Pal diminishes from 4.58 eV at ambient pressure to 4.39 eV, resulting in an increase in conductivity. Subsequent density of states (DOS) analysis corroborates that the reduction in Pal's band gap is predominantly ascribed to the increased contribution of Si 3 s orbitals at 20 GPa. Additionally, the examination of elastic constants reveals a substantial augmentation in shear rigidity along the a-c and b-c planes, which further facilitates the narrowing of the band gap. The Gibbs free energy of adsorbed hydrogen (Δ<em>G</em><sub>H⁎</sub>) DFT calculation results further confirm that the bandgap-narrowed Pal at 20 GPa displays enhanced catalytic performance for hydrogen evolution. Notably, despite significant structural reconfigurations under high pressure, Pal maintains negative binding energies and shows no phase transition, demonstrating exceptional structural stability. This study offers theoretical insights and guidance for optimizing the performance of Pal in a plethora of sophisticated technological applications.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"278 ","pages":"Article 108010"},"PeriodicalIF":5.8,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145262933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}