Small Structures最新文献

{"title":"Small-Molecule Polycyclic Aromatic Hydrocarbons as Exceptional Long-Cycle-Life Li-Ion Battery Anode Materials","authors":"Avi Arya, Sih-Ling Hsu, Chi-You Liu, Meng-Yuan Chang, Jeng-Kuei Chang, Elise Yu-Tzu Li, Yu-Sheng Su","doi":"10.1002/sstr.202400273","DOIUrl":"https://doi.org/10.1002/sstr.202400273","url":null,"abstract":"The growing demand for cost-effective and sustainable energy-storage solutions has spurred interest in novel anode materials for lithium-ion batteries (LIBs). In this study, the potential of small-molecule polycyclic aromatic hydrocarbons (SMPAHs) as promising candidates for LIB anodes is explored. Through a comprehensive experimental approach involving electrode fabrication, material characterization, and electrochemical testing, the electrochemical performance of SMPAHs, including naphthalene, biphenyl, 9,9-dimethylfluorene, phenanthrene, <i>p</i>-terphenyl, and pyrene (Py), is thoroughly investigated. In the results, the impressive cycle stability, high specific capacity, and excellent rate capability of the SMPAH electrode are revealed. Additionally, a direct contact prelithiation strategy is implemented to enhance the initial Coulombic efficiency (ICE) of SMPAH anodes, yielding significant improvements in the ICE and cycle stability. Computational simulations provide valuable insights into the electrochemical behavior and lithium-storage mechanisms of SMPAHs, confirming their potential as effective anode materials. The simulations reveal favorable lithium adsorption sites, the predominant storage mechanisms, and the dissolution mechanism of Py through computational calculations. Overall, in this study, the promise of SMPAHs is highlighted as sustainable anode materials for LIBs, advancing energy-storage technologies toward a greener future.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatially Selective Ultraprecision Polishing and Cleaning by Collective Behavior of Micro Spinbots","authors":"Hyeongmin Je, Sukyoung Won, Jeong Jae Wie, Sanha Kim","doi":"10.1002/sstr.202400245","DOIUrl":"https://doi.org/10.1002/sstr.202400245","url":null,"abstract":"Untethered magnetic actuation is an attractive technique for controlling a batch of micrometer-sized soft robots. Recent advancements have enabled each robot to follow its path independently using a single magnetic device. However, applications of magnetic soft microrobots are mostly biased toward the biomedical field. In this study, thermoplastic polyurethane–Fe₃O₄ nanocomposite soft spinning microrobots, that is, spinbots that actuate on a tabletop magnetic stirrer, were utilized as innovative precision manufacturing tools for spatially selective precision polishing and cleaning. The pivot motion of the revolving spinbots, which involves repetitive sweeping during rotation cycles, is explored. This sweeping action physically removes nanometer-sized surface contaminants from the workpiece, achieving a cleaning efficiency of 99.6%. Multiple spinbots, up to 42 in total, simultaneously operated along their own orbital pathways on three vertically stacked wafers, thereby demonstrating an unprecedented cleaning method. In addition, the spinbots precisely removed materials from the workpiece using a three-body abrasion mechanism. Furthermore, the spinbots contributed to precise material removal, resulting in remarkable surface polishing (<i>R</i>\u0000_a ≈ 1.8 nm). This novel polishing system, which uses the collective behavior of multiple spinbots on a tabletop magnetic stirrer, is 1000-fold lighter than current state-of-the-art equipment aimed at achieving similar levels of fine finishing.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single Site W(0) versus Re(I)-Dipyridophenazine- Based Conjugated Porous Polymer for CO2 Photoreduction","authors":"Ángela Matarín, Félix Sánchez, Laura Collado, Mariam Barawi, Victor A. de la Peña O'Shea, Avelina Arnanz, Marta Liras, Marta Iglesias","doi":"10.1002/sstr.202400185","DOIUrl":"https://doi.org/10.1002/sstr.202400185","url":null,"abstract":"Herein, the synthesis and characterization of two robust tungsten and rhenium carbonyl complexes integrated into an organic polymer (<b>CPP-Re</b>, <b>CPP-W</b>) are reported. These polymers are obtained by a Suzuki coupling reaction between the corresponding dibromo metal-carbonyl substituted dipyrido[3,2-a:2′,3′-c]phenazine complex and 1,3,5-triphenylbenzene-4′,4″,4″,4‴-triboronic acid and integrated catalytic active sites and photosensitizer since they have not only nitrogen sites to coordinate metal active centers as rhenium or tungsten but photoactive units with good charge-separating ability which can significantly improve the CO₂ photoreduction reaction (CO₂PRR). These polymers show similar activity in solid–gas CO₂PRR in absence of sacrificial agents to produce syn gas (CO + H₂) but <b>CPP</b><b>-W</b> selectivity to products change regarding <b>CPP-Re</b> being able to produce also large amount of more demanding electron products such as methane and ethane. Moreover, the single-site <b>Re-</b> or <b>W-CPP</b> catalysts could prevent the dimerization of complexes that produces its deactivation. This work shows the potential of CPPs as matrices to support single active centers for heterogeneous catalysis.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"182 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling Inequality of Atoms in Ultrasmall Pt Clusters: Oxygen Adsorption Limited to the Uppermost Atomic Layer","authors":"Federico Loi, Luca Bignardi, Deborah Perco, Andrea Berti, Paolo Lacovig, Silvano Lizzit, Aras Kartouzian, Ulrich Heiz, Dario Alfè, Alessandro Baraldi","doi":"10.1002/sstr.202400250","DOIUrl":"https://doi.org/10.1002/sstr.202400250","url":null,"abstract":"The concept of preferential atomic and molecular adsorption site is of primary relevance in heterogeneous catalysis. In the case of ultrasmall size-selected clusters, distinguishing the role played by each atom in a reaction is extremely challenging due to their reduced size and peculiar structures. Herein, it is revealed how the inequivalent atoms composing graphene-supported Pt₁₂ and Pt₁₃ clusters behave differently in the photoinduced dissociation of O₂, with only those in the uppermost layer of the clusters being involved in the reaction. In this process, the epitaxial graphene support plays a fundamental active role: its corrugation and pinning induced by the presence of the clusters are crucial for defining the preferential adsorption site on the Pt atomic agglomerates, facilitating the lateral diffusion of physisorbed oxygen at a distance that induces its selective adsorption in the topmost layer of the clusters, and inducing an inhomogeneous charge distribution within the clusters which directly affects the O₂ adsorption. The inhomogeneous oxidation of the clusters is resolved by means of synchrotron-based X-ray photoelectron spectroscopy and supported by ab initio density functional theory calculations. The possibility to identify the active sites on Pt clusters induced by cluster–support interactions has the potential to enhance the experimentally supported design of nanocatalysts.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep-Learning-Assisted Affinity Classification for Humoral Immunoprotein Complexes","authors":"Bahar Dadfar, Safoura Vaez, Cristian Haret, Meike Koenig, Tahereh Mohammadi Hafshejani, Matthias Franzreb, Joerg Lahann","doi":"10.1002/sstr.202400204","DOIUrl":"https://doi.org/10.1002/sstr.202400204","url":null,"abstract":"Immunoglobulins are important building blocks in biology and biotechnology. With the emergence of comprehensive deep-learning approaches, there are enormous opportunities for fast and accurate methods of classification of protein–protein interactions to arise. Herein, widely accessible image classification algorithms for species-specific typification of a range of different immunoglobulin G (IgG) complexes are repurposed. Droplets of various immunoglobulins mixed with a B-cell superantigen (SAg) (recombinant staphylococcal Protein A) are deposited onto hydrophobic polymer substrates and the resulting protein stains are imaged using polarized light microscopy. A comprehensive study based on 23 745 images finds that the pretrained convolutional neural network (CNN) InceptionV3 not only successfully categorizes IgGs from four different species but also predicts their binding affinity to Protein A: averaged over 36 binding pairs, the following are observed: 1) an overall accuracy of 81.4%, 2) the highest prediction accuracy for human IgG, the antibody with the highest binding affinity for Protein A, and 3) that the classification accuracy regarding the various IgG/Protein A ratios generally correlates with the binding strength of the protein–protein–complex as determined via circular dichroism spectroscopy. In addition, the CNN pretrained with IgG/Protein A stain images has been challenged with a new set of images using a different superantigen (SAg, Protein G). Despite the use of the unknown SAg, the CNN correctly classifies the images of human IgG and Protein G as indicated by a 94% accuracy over the various molar binding ratios. These findings are noteworthy because they demonstrate that appropriately pretrained CNNs can be used for the prediction of protein–protein interactions beyond the scope of the original training set. Aided by deep-learning methods, simple stains of mixed protein solutions may serve as accurate predictors of the strength of protein–protein interactions with relevance to protein engineering, self-aggregation, or protein stability in complex media.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas-Shearing Microfluidic Fabrication of Polydiacetylene–Alginate Colorimetric Sensor Beads","authors":"Narges Ahmadi, Dong Yun Kim, Seung Soo Shin, Sneha Daradmare, Jong-Man Kim, Bum Jun Park","doi":"10.1002/sstr.202400340","DOIUrl":"https://doi.org/10.1002/sstr.202400340","url":null,"abstract":"Polydiacetylenes (PDA) are highly regarded for their unique colorimetric and fluorescent responses, making them ideal for sensor development. Despite their potential, conventional methods for fabricating biocompatible PDA-encapsulated hydrogel sensor beads often fail to offer precise control over bead size and morphology. This study introduces a coflow gas-shearing microfluidic system that effectively overcomes these limitations, enabling the controlled production of polydiacetylene/alginate (PDA/Alg) and polydiacetylene/polydimethylsiloxane/alginate (PDA/PDMS/Alg) microbeads. Through systematic variation of gas pressure, liquid flow rates, and nozzle sizes, the mechanisms of droplet breakup and generation are explored. This process is validated through numerical modeling based on the Weber number, which enhances our understanding of droplet size distribution and flow regimes. The solvatochromic properties of PDA/Alg microbeads are assessed, highlighting their potential as polar solvent sensors and discussing the solvatochromic mechanism in terms of intermolecular interactions and the dissolution of unpolymerized monomers. Additionally, PDA/PDMS/Alg microbeads exhibit a semireversible thermochromic response under repeated cycles of heating, cooling, and UV exposure. This response is attributed to the formation of new PDA domains inside the PDMS phase upon UV exposure onto the red-phase microbeads. Overall, this study successfully demonstrates a straightforward and effective microfluidic approach for producing well-defined stimulus-responsive PDA–hydrogel microbeads.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Negative Charge Carbon Dots Manufacturing Electrostatic Shielding Layer for Stable Zinc Anode","authors":"Kai Wang, Jinqiang Gao, Huaxin Liu, Weishun Jian, Jiangnan Huang, XinYu Hu, Siyuan Lai, Yafei Li, Guoqiang Zou, Hongshuai Hou, Wentao Deng, Xiaobo Ji","doi":"10.1002/sstr.202400343","DOIUrl":"https://doi.org/10.1002/sstr.202400343","url":null,"abstract":"Alkaline zinc-based batteries (AZBs) can yield higher operating voltages due to a more negative electrode potential of zinc metal in alkaline electrolytes compared with neutral electrolytes, delivering high energy density in practical manufacturing applications. However, AZBs also exhibit more pronounced problems due to severe corrosion of the zinc anode by the strongly alkaline electrolyte environment. Combined with the reaction mechanism of alkaline zinc batteries, negatively charged carbon dots are innovatively used to construct a barrier with both physical and chemical effects. Zinc anode exposure to electrolyte is reduced by superior barrier, which assures transmission of zinc ions rather than zincate ions through electrostatic force balance, thus improving the distribution of the electric field for zinc ion deposition as well as avoiding accumulation of zincate ions at the interface. The number of harmful dendrite formation was found to be significantly suppressed by in situ optical microscopy. When coupled with silver oxide cathode for testing, the assembled silver-zinc battery results in a significant enhancement in its cyclic life. It is believed that this study will propel the development of zinc anode in alkaline batteries and provide new insights for their application.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Universal Synthesis of Core–Shell-Structured Ordered Mesoporous Transition Metal Dichalcogenides/Metal Oxides Heterostructures with Active Edge Sites","authors":"Zhenliang Li, Yujian Rao, Zhehan Wang, Tuo Zhang, Guodong Wu, Litao Sun, Yuan Ren, Li Tao","doi":"10.1002/sstr.202400376","DOIUrl":"https://doi.org/10.1002/sstr.202400376","url":null,"abstract":"Two-dimensional (2D) transition metal dichalcogenides (TMDs) are widely used in interfacial reactions and electronic devices due to their tunable bandgap and high efficiency of carrier transport. However, the lack of fully exposed active sites in bulk samples or stacked nanosheets leads to limited performances. In this work, a general method is developed to construct ordered mesoporous TMDs/metal oxides (OM-TMDs/MOs) heterostructures, including WS&lt;sub&gt;2&lt;/sub&gt;/WO&lt;sub&gt;3&lt;/sub&gt;, WSe&lt;sub&gt;2&lt;/sub&gt;/WO&lt;sub&gt;3&lt;/sub&gt;, WTe&lt;sub&gt;2&lt;/sub&gt;/WO&lt;sub&gt;3&lt;/sub&gt;, MoS&lt;sub&gt;2&lt;/sub&gt;/MoO&lt;sub&gt;3&lt;/sub&gt;, and V&lt;sub&gt;3&lt;/sub&gt;S&lt;sub&gt;4&lt;/sub&gt;/V&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;, through one-step thermal sulfurization (selenidation/tellurization) of self-assembled amphiphilic block copolymer/polyoxometalates clusters nanocomposites with ordered mesostructures. The OM-TMDs/MOs possess highly OM structures with high specific surface area, large pore size, and rich active edge sites in the frameworks of heterostructures. The chemiresistive gas sensor based on OM-WS&lt;sub&gt;2&lt;/sub&gt;/WO&lt;sub&gt;3&lt;/sub&gt; shows excellent NO&lt;sub&gt;2&lt;/sub&gt;-sensing performances at room temperature, with high sensitivity, ultrahigh selectivity (&lt;span data-altimg=\"/cms/asset/a3e5cd6e-ac04-41a3-b6e2-cce80c9d4d74/sstr202400376-math-0001.png\"&gt;&lt;/span&gt;&lt;mjx-container ctxtmenu_counter=\"3\" ctxtmenu_oldtabindex=\"1\" jax=\"CHTML\" role=\"application\" sre-explorer- style=\"font-size: 103%; position: relative;\" tabindex=\"0\"&gt;&lt;mjx-math aria-hidden=\"true\" location=\"graphic/sstr202400376-math-0001.png\"&gt;&lt;mjx-semantics&gt;&lt;mjx-mrow&gt;&lt;mjx-msub data-semantic-children=\"0,3\" data-semantic- data-semantic-role=\"latinletter\" data-semantic-speech=\"upper S Subscript NO Sub Subscript 2\" data-semantic-type=\"subscript\"&gt;&lt;mjx-mi data-semantic-annotation=\"clearspeak:simple\" data-semantic-font=\"italic\" data-semantic- data-semantic-parent=\"4\" data-semantic-role=\"latinletter\" data-semantic-type=\"identifier\"&gt;&lt;mjx-c&gt;&lt;/mjx-c&gt;&lt;/mjx-mi&gt;&lt;mjx-script style=\"vertical-align: -0.15em; margin-left: -0.032em;\"&gt;&lt;mjx-mrow size=\"s\"&gt;&lt;mjx-msub data-semantic-children=\"1,2\" data-semantic- data-semantic-parent=\"4\" data-semantic-role=\"unknown\" data-semantic-type=\"subscript\"&gt;&lt;mjx-mrow&gt;&lt;mjx-mtext data-semantic-annotation=\"clearspeak:unit\" data-semantic-font=\"normal\" data-semantic- data-semantic-parent=\"3\" data-semantic-role=\"unknown\" data-semantic-type=\"text\"&gt;&lt;mjx-c&gt;&lt;/mjx-c&gt;&lt;mjx-c&gt;&lt;/mjx-c&gt;&lt;/mjx-mtext&gt;&lt;/mjx-mrow&gt;&lt;mjx-script style=\"vertical-align: -0.15em;\"&gt;&lt;mjx-mn data-semantic-annotation=\"clearspeak:simple\" data-semantic-font=\"normal\" data-semantic- data-semantic-parent=\"3\" data-semantic-role=\"integer\" data-semantic-type=\"number\" size=\"s\"&gt;&lt;mjx-c&gt;&lt;/mjx-c&gt;&lt;/mjx-mn&gt;&lt;/mjx-script&gt;&lt;/mjx-msub&gt;&lt;/mjx-mrow&gt;&lt;/mjx-script&gt;&lt;/mjx-msub&gt;&lt;/mjx-mrow&gt;&lt;/mjx-semantics&gt;&lt;/mjx-math&gt;&lt;mjx-assistive-mml display=\"inline\" unselectable=\"on\"&gt;&lt;math altimg=\"urn:x-wiley:26884062:media:sstr202400376:sstr202400376-math-0001\" display=\"inline\" location=\"graphic/sstr202400376-math-0001.png\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;semantics&gt;&lt;","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"425 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rethinking Models of DNA Organization in Micrometer-Sized Chromosomes from the Perspective of the Nanoproperties of Chromatin Favoring a Multilayer Structure","authors":"Joan-Ramon Daban","doi":"10.1002/sstr.202400203","DOIUrl":"https://doi.org/10.1002/sstr.202400203","url":null,"abstract":"The long genomic DNA molecules in eukaryotes are fragile and prone to entanglement, and must be tightly folded to fit into the micrometric dimensions of mitotic chromosomes. Histones transform the monotonous linear structure of double-helical DNA into a chromatin filament formed by many nucleosomes. A physically consistent model for the packaging of the chromatin filament must be compatible with all the constraints imposed by the structural properties of chromosomes. It has to be compatible with 1) the high concentration of DNA and the elongated cylindrical shape of chromosomes and 2) the known self-associative properties of chromatin, and also with 3) an effective protection of chromosomal DNA from topological entanglement and mechanical breakage. The multilayer chromosome model, in which a repetitive weak interaction between nucleosomes at the nanoscale produces the stacking of many chromatin layers, is compatible with all these constraints. The self-organization of the multilayer structure of the whole chromosome is consistent with current knowledge of the self-assembly of micrometric structures from different repetitive building blocks. The multilayer model justifies the geometry of chromosome bands and translocations, and is compatible with feasible physical mechanisms for the control of gene expression, and for DNA replication, repair, and segregation to daughter cells.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Directionally Cracked Mesoporous Colloidal Films by Manipulating Notch Angles and Their Anisotropic Wicking Behavior","authors":"Yunchan Lee, Min-Gi Jo, Seongwoo Jeon, Chorong Kim, Jaekyoung Kim, Sanghyuk Wooh, Kee-Youn Yoo, Hyunsik Yoon","doi":"10.1002/sstr.202400159","DOIUrl":"https://doi.org/10.1002/sstr.202400159","url":null,"abstract":"Wicking in porous media, such as the spreading of ink on paper or the absorption of moisture by fabric, occurs when water interacts with hydrophilic porous materials through capillary action and evaporation. The directional nature of the wicking phenomenon can be leveraged for various advanced applications, including enhanced heat transfer, colorimetric devices, energy harvesting, and microfluidics. Herein, crack generation is used to induce the anisotropic wicking of water on isolated mesoporous strips. The strips are fabricated by transforming isotropic cracks into anisotropic ones in micropyramid arrays using the <i>Poisson</i> effect in elastomeric blocks. Stretching an elastomeric block increases the period of a pyramid array along one direction while decreasing it in the perpendicular direction because of elastomer shrinkage. This amplifies the difference in the notch angles of pyramidal edges between parallel and perpendicular directions relative to the stretching axis. Consequently, the disparity in notch angles leads to preferential crack generation owing to elevated stress localization on the sharpened notches. Directional wicking is demonstrated using anisotropic strips of mesoporous TiO₂ colloidal films and highly anisotropic wicking of ink is illustrated by coating hydrophobic films on mesoporous strips. The anisotropic wicking observed in cracked mesoporous strips can serve as 1D microfluidic channels.","PeriodicalId":21841,"journal":{"name":"Small Structures","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}