Chemistry of Materials最新文献

{"title":"Grain Boundary Engineering in Bottom-Up Synthesized Thermoelectric Nanocomposites","authors":"Xumeng Jia,&nbsp;Cheng Chang* and Li-Dong Zhao*,&nbsp;","doi":"10.1021/acs.chemmater.5c01791","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01791","url":null,"abstract":"<p >Grain boundaries play a critical role in determining the thermoelectric performance of materials by simultaneously influencing electrical and thermal transport. Compared to conventional composites synthesized via melting-annealing methods, nanocomposites prepared through wet-chemical routes are more susceptible to grain boundary effects due to their high specific surface area. However, most previous studies have primarily focused on tuning the composition of nanoparticles, while grain boundary engineering has been relatively underexplored. In this perspective, we first review the general mechanisms of energy filtering and low-frequency phonon scattering at grain boundaries and their contributions to thermoelectric enhancement. We then highlight three promising bottom-up strategies for grain boundary engineering via nanoparticle surface modification: nanoparticle blending, colloidal exchange, and small-molecule recovery. Finally, we outline several key questions and challenges that future research must address to further advance this field.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6443–6449"},"PeriodicalIF":7.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing the Performance of Lithium-Rich Oxides in Cooperation with Inherent Complexities: Engineering Domain Structure","authors":"Juan C. Garcia,&nbsp;Hakim Iddir,&nbsp;Arturo Gutierrez,&nbsp;Subhadip Mallick,&nbsp;Yulin Lin,&nbsp;Jianguo Wen,&nbsp;Fulya Dogan,&nbsp;Hari Adhikari and Jason R. Croy*,&nbsp;","doi":"10.1021/acs.chemmater.5c00828","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c00828","url":null,"abstract":"<p >The nanodomain structure of lithium- and manganese-rich, composite cathode materials has been systematically altered through synthesis conditions while keeping larger-scale morphological differences to a minimum. Clear changes in electrochemical performance across the samples studied are observed, especially with respect to the anomalous impedance at low states-of-charge. Atomic-scale modeling, coupled to electrochemical measurements and physical characterization, reveals the local consequences of the high-voltage activation charge process as a function of specific domain structures. Furthermore, the results explain the influence of different postactivation structures on the insertion of Li-ions and the associated impedance during discharge. This work adds to our series of studies on lithium- and manganese-rich oxides, demonstrating that the inherent performance of LMRs can be greatly enhanced through rational, highly controlled synthetic strategies based on an understanding of synthesis–structure–property relationships across length scales.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6500–6511"},"PeriodicalIF":7.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controlling Polymer Electrolyte Interfacial Morphology through Chemical Interactions","authors":"Joseph A. Dura*,&nbsp;Sangcheol Kim,&nbsp;Kirt A. Page and Christopher L. Soles,&nbsp;","doi":"10.1021/acs.chemmater.5c01738","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01738","url":null,"abstract":"<p >Owing to its unique mechanical properties, chemical resistance, and ion conductivity, Nafion is one of the most widely used polymer electrolytes. In hydrogen fuel cells, it constitutes both the macroscopic membrane separating the anode and the cathode, and as a thin film, Nafion appears as a binder in the catalyst layer where conductive ionic pathways must intimately interface with platinum catalyst particles, electrically conductive carbon particles, and porous surfaces that facilitate the transport of gases. Residing at the intersection of this diverse range of materials, the ionomer’s interfacial structure influences interfacial impedance and thus device performance. This interface structure has been widely investigated on model surfaces with neutron reflectometry and other techniques, resulting in the discovery of a multilamellar structure at the interface with hydrophilic materials, or a single water-rich layer at the interface with, e.g., metals, favoring tangential vs perpendicular ion transport, respectively. Here we demonstrate that self-assembled monolayers, SAMs, which can coat various surfaces, can control whether single or multiple lamellae occur. These interfacial structures can be further modified through acid–base interactions by protonating the terminal amine group of a SAM at low pH. This establishes a methodology to control the interfacial ionic transport pathways in Nafion and determine the interfacial impedance.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6921–6931"},"PeriodicalIF":7.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.5c01738","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiobjective Platform for Autonomous Property Targeting and Optimization of Colloidal Lead Halide Perovskite Quantum Dots","authors":"Neal Munyebvu,&nbsp;Steve Dunn and Philip D. Howes*,&nbsp;","doi":"10.1021/acs.chemmater.5c01153","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01153","url":null,"abstract":"<p >The optimization of colloidal quantum dot (CQD) materials, synthesis routes, and processing methods are complex challenges that are ripe for automation and artificial intelligence (AI) to have a great impact. These optimization challenges are seldom oriented to a single target; therefore, it is vital that autonomous systems can handle multiple objectives. In this work, we present an autonomous CQD synthesis system that successfully performs multiobjective optimization (MOO) via Bayesian optimization-based algorithms. We demonstrate the efficacy of the system through three distinct synthesis challenges, based on one, two, and three objective optimization problems, in the synthesis of cesium lead halide perovskite CQDs. Objectives included maximizing fluorescence brightness, minimizing particle size dispersity, and targeting of a specific optical band gap and particle diameter. The triobjective challenge achieved simultaneous targeting of specific CQD sizes and band gaps independently via reaction tuning and halide doping, while minimizing the particle size dispersity. This work demonstrates AI-assisted multiobjective targeting and dynamic synthesis of targeted colloidal CQDs using exciton energy analysis of absorption spectra to infer both size and optical band gap. It presents an accessible, automated, and data-driven platform for CQD discovery and optimization (both for single and multiple objectives), highlighting the promise of widespread integration of AI-guided strategies into CQD R&amp;D.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6629–6641"},"PeriodicalIF":7.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.5c01153","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Insights into Lithium-Ion Coordination and Morphology in Carbonate Polymer Electrolytes","authors":"Omar Allam,&nbsp; and ,&nbsp;Seung Soon Jang*,&nbsp;","doi":"10.1021/acs.chemmater.5c01016","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01016","url":null,"abstract":"<p >Research of solid-state polymer electrolytes (SPEs) has accelerated due to their promise to address critical barriers in lithium-ion and lithium-metal battery commercialization through their superior thermal stability, reduced flammability, and mitigation of dendrite formation. In this study, we employ all-atom molecular dynamics simulations to investigate the <i>Li</i>⁺ solvation structure, ion diffusion, and phase morphology in mixtures of ethylene carbonate (EC) and dimethyl carbonate (DMC) across various salt concentrations. Our findings indicate that low salt concentrations diminish ionic interactions and enhance ion mobility, whereas elevated salt levels facilitate ion clustering and reduce ion mobility. Based on these findings, solid polymer electrolytes were designed using EC and DMC moieties. Polymers incorporating DMC exhibit greater backbone flexibility and lower glass transition temperatures than their EC-based counterparts resulting in an ion transport enhancement. The study also examines mixed-branch copolymer systems and polymer blend systems as alternative approaches for tuning mechanical and ionic transport properties. Both direct copolymerization and physical blending of single-branch polymers allow fine-tuning of mechanical and electrochemical properties. Notably, at elevated salt concentrations, <i>Li</i>⁺ ions act as compatibilizers that reduce phase separation. These findings contribute to a fundamental understanding of the relationships among the polymer structure, salt concentration, and ion transport in carbonate-based polymer electrolytes.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6574–6584"},"PeriodicalIF":7.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.5c01016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intrinsically Ultra-low Lattice Thermal Conductivity and Excellent Thermoelectric Performance in Complex Layered Pb4In2.8Bi3.2Se13 Compound","authors":"Xi Peng,&nbsp;Xili Wen,&nbsp;Hao Luo,&nbsp;Zhi Li,&nbsp;Jinxin Guo,&nbsp;Xianli Su*,&nbsp;Jinsong Wu,&nbsp;Vladimir Khovaylo,&nbsp;Pierre Ferdinand Poudeu Poudeu,&nbsp;Qingjie Zhang and Xinfeng Tang*,&nbsp;","doi":"10.1021/acs.chemmater.5c01634","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01634","url":null,"abstract":"<p >The complex atomic structure of the Pb₄In_2.8Bi_3.2Se₁₃ compound has been investigated, crystallizing in orthorhombic <i>Pbam</i> (<i>a</i> = 22.093 Å, <i>b</i> = 27.398 Å, <i>c</i> = 4.1324 Å). Its crystal structure exhibits a 3D framework, wherein bicapped trigonal prisms of Pb²⁺ ions bridge InSe₄ tetrahedra and (Bi/In)Se₆ octahedra. This framework incorporates <i>Z</i>-shaped chains of distorted Bi³⁺ octahedra and linear chains of In³⁺ tetrahedra propagating along the <i>c</i>-axis. The synergistic effects of Pb/Bi s² lone-pair electron distortion-induced coordination environments and weak In–Se covalent bonds significantly suppress phonon propagation, resulting in intrinsically low <i>v</i>_a (1689 m s^–1) and ultra-low <i>θ</i>_D (86 K). These collectively enable intrinsically ultra-low <i>κ</i>_L (0.27 W m^–1 K^–1 at 723 K). Meanwhile, electronic transport properties were effectively optimized by doping with Cl, achieving a peak <i>PF</i> of 0.23 mW m^–1 K^–2 at 723 K. Consequently, the Cl-doped Pb₄In_2.8Bi_3.2Se_12.805Cl_0.195 compound reached <i>ZT</i> = 0.54 at 723 K, representing a 260% improvement over the undoped intrinsic sample.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6837–6845"},"PeriodicalIF":7.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and Transport Properties in the Pseudobinary Phase System Li4SiS4–Li4SnS4","authors":"Lucas G. Balzat,&nbsp;Yan Li,&nbsp;Sascha Dums,&nbsp;Igor Moudrakovski,&nbsp;Kristina Gjorgjevikj,&nbsp;Armin Schulz,&nbsp;Yuheng Li,&nbsp;Simon Krause,&nbsp;Pieremanuele Canepa* and Bettina V. Lotsch*,&nbsp;","doi":"10.1021/acs.chemmater.5c00358","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c00358","url":null,"abstract":"<p >Thio-lithium superionic conductors (thio-LISICONs) are a family of promising solid electrolyte materials for potential applications in solid-state batteries. The orthorhombic polymorph of the thio-LISICON Li₄SiS₄ (<i>o</i>-Li₄SiS₄) has been known for decades, but its complete crystal structure has been reported only recently. Here, using single-crystal X-ray diffraction, we reevaluated the crystal structure of <i>o</i>-Li₄SiS₄ and showed that <i>o</i>-Li₄SiS₄ crystallizes in space group <i>Pmn</i>2₁ (no. 31, <i>a</i> = 7.7694(15) Å, <i>b</i> = 13.731(3) Å, and <i>c</i> = 6.1413(12) Å). The crystal structure of <i>o</i>-Li₄SiS₄ consists of isolated SiS₄ tetrahedra arranged in a zigzag-type manner, whereas Li atoms are coordinated both tetrahedrally and octahedrally by sulfur atoms of the SiS₄ groups. Structures identified by first-principles calculations support the lower symmetry solution presented here, with the <i>Pmn</i>2₁ polymorph being more stable at room temperature than a higher symmetry phase. By knowing the accurate crystal structure of <i>o</i>-Li₄SiS₄, we investigated the solid solution behavior with another group IV thio-LISICON, Li₄SnS₄. Rietveld refinements of powder X-ray diffraction data revealed the solid solution Li₄Si_1–<i>x</i>Sn<i>_<i>x</i></i>S₄ (0 ≤ <i>x</i> ≤ 1, Δ<i>x</i> = 0.1), which shows a nearly ideal Vegard-type behavior for all silicon-containing samples. ²⁹Si and ¹¹⁹Sn magic-angle-spinning solid-state NMR and Raman spectroscopy showed the presence of SiS₄ and SnS₄ tetrahedral moieties, with the spectra showing expected behavior consistent with the silicon–tin ratio in the materials. Electrochemical impedance spectroscopy revealed the highest ionic conductivity of 8.4 × 10^–6 S cm^–1 at 25 °C for Li₄Si_0.5Sn_0.5S₄, accompanied by the lowest migration barrier of ∼0.37 eV.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 16","pages":"6127–6139"},"PeriodicalIF":7.0,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.5c00358","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144894592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Density of States Prediction by a Metric-Optimized Equivariant Graph Neural Network","authors":"Jiayang Xie,&nbsp;Zhihao Zhang and Xiao-Ming Cao*,&nbsp;","doi":"10.1021/acs.chemmater.5c01359","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01359","url":null,"abstract":"<p >Density of states (DOS) is a crucial factor in elucidating the physical and functional properties of materials, playing a significant role in materials design. However, traditional density functional theory (DFT) calculations of DOSs are computationally expensive and inefficient, particularly when dealing with large structures and high-throughput electronic structure calculations. To address this challenge, we propose a metric-optimized equivariant graph neural network, called EqDOS, for DOS prediction, which can efficiently learn interatomic interactions from atomic position information. This capability allows the model to accurately predict DOS even with limited data, exhibiting excellent generalization capability. Additionally, by incorporating probability distribution metrics of high-order difference and Wasserstein distance for multiobjective learning, we effectively address the issues of oversmoothness and the sensitivity of sharp peaks in DOS curve prediction. These are especially important when handling materials with multiple compositions and structures in the periodic table. EqDOS enables the zero-shot prediction on the DOS profiles of ternary single-atom alloy surfaces with excellent performance outcomes, using the well-trained model based on the binary alloy surface data set. Furthermore, the predicted DOS by our model could serve as input for the downstream material performance prediction models. The results show that our model not only achieves higher accuracy in DOS curve fitting but also performs exceptionally well on the prediction of adsorption energy when combined with a downstream DOS Transformer for Adsorption (DOTA) model. This confirms that our model can accurately predict the DOS while preserving its physical significance. These findings not only validate the generalization and effectiveness of our model framework but also provide a new tool for the field of materials science to accelerate the discovery and optimization of new materials.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 16","pages":"6313–6322"},"PeriodicalIF":7.0,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144894695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulating Thermometric Performance via Dopant Concentration and Morphology in a Luminescence Thermometer Exhibiting Dual Structural Phase Transitions","authors":"Malgorzata Kubicka,&nbsp;Maja Szymczak,&nbsp;Maciej Ptak,&nbsp;Damian Szymanski,&nbsp;Vasyl Kinzhybalo,&nbsp;Marek Drozd and Lukasz Marciniak*,&nbsp;","doi":"10.1021/acs.chemmater.5c00881","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c00881","url":null,"abstract":"<p >Expanding the operational range of luminescent thermometers that utilize thermally induced structural phase transitions in lanthanide-doped materials necessitates the exploration of novel host matrices with diverse thermal behaviors. In line with this objective, this study offers a comprehensive analysis of the temperature-dependent spectroscopic properties of Li₃Sc₂(PO₄)₃:Eu³⁺. The findings reveal that the studied material undergoes two reversible phase transitions: the γ_LT → α/β phase transition at approximately 160 K, followed by a β → γ _HT transition around 550 K. These transitions are evidenced by notable alterations in the emission spectra and luminescence decay kinetics of Eu³⁺ ions. By employing an appropriate luminescence intensity ratio, the sensitivity was determined to be 7.8% K^–1 at 160 K for 0.1% Eu³⁺ and 0.65% K^–1 at 550 K for 0.5% Eu³⁺. Furthermore, the study demonstrates that the phase transition temperature in Li₃Sc₂(PO₄)₃:Eu³⁺ can be modulated through variations in dopant ion concentration and annealing conditions, which in turn influence the material’s morphology. These strategies enable the fine-tuning of thermometric performance in phase transition-based luminescent thermometers. To the best of our knowledge, this represents the first report in the literature of a luminescent thermometer exhibiting dual thermal operating ranges.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6522–6533"},"PeriodicalIF":7.0,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.5c00881","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controlling Surface-Enhanced Raman Scattering and Metal-Enhanced Fluorescence in Silver Nanofilms Using Ultrathin Aluminum Oxide Spacers via Atomic Layer Deposition","authors":"Isabela Machado Horta*,&nbsp;Nilton Francelosi Azevedo Neto,&nbsp;Claudio Téllez Zepeda,&nbsp;Carlos E. Gomes,&nbsp;Natali da Silva Barbosa,&nbsp;André Jesus Pereira,&nbsp;Argemiro Soares da Silva Sobrinho and Rodrigo Pessoa*,&nbsp;","doi":"10.1021/acs.chemmater.5c01585","DOIUrl":"https://doi.org/10.1021/acs.chemmater.5c01585","url":null,"abstract":"<p >Atomic layer deposition (ALD) enables simultaneous passivation of silver and nanometer-scale tuning of the near-field landscape that controls surface-enhanced Raman scattering (SERS) and metal-enhanced fluorescence (MEF). Here, sputtered ∼16 nm Ag films were conformally coated with 1–20 ALD cycles of Al₂O₃ (≈0.17–1.76 nm) and analyzed by atomic force microscopy (AFM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), spectroscopic ellipsometry, UV–Vis spectroscopy, time-resolved fluorescence, large-area Raman mapping of Rhodamine 6G and finite-difference time-domain (FDTD) modeling. Morphology evolves from isolated oxide nuclei after one cycle through a conformal roughness-amplifying shell at 5–15 cycles to vertically elongated outgrowths at 20 cycles; ellipsometry confirms self-limiting growth with 0.10 ± 0.02 nm cycle^–1. Optical measurements reveal three thickness regimes: ≤1 cycle (&lt;0.2 nm) yields SERS-dominated behavior with picosecond quenching and intense Raman hotspots; ∼5 cycles (∼0.5 nm) provides the hybrid optimum, giving the highest Raman enhancement (EF ≈ 2 × 10³) together with a 4-fold fluorescence-lifetime extension (⟨τ⟩ ≈ 26 ns) that signals strong MEF; whereas &gt;10 cycles (&gt;1 nm) attenuate both SERS and MEF as the evanescent field decays. FDTD maps based on AFM topographies reproduce the heavy-tailed hotspot distribution and identify the 0.5–1.0 nm window as the sweet spot for co-optimizing field confinement and radiative efficiency. Stability tests show that five-cycle coatings endure solvent rinsing and cotton-swab abrasion while retaining─or even increasing─SERS activity, whereas thicker oxides guarantee mechanical integrity at the cost of weaker near-fields. These combined results show an experimentally validated framework for engineering reusable, dual-mode plasmonic substrates by angstrom-level control of dielectric spacer thickness.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"37 17","pages":"6791–6806"},"PeriodicalIF":7.0,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.5c01585","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}