The Journal of Physical Chemistry C最新文献

{"title":"Effect of Cation Cu/Al Ratio and Surface Proximity on the Electronic Structure and Optical Properties of Cu-Rich Cu1+xAl1–xS2–y: A DFT Study","authors":"O. Volnianska, Ł. Kłopotowski","doi":"10.1021/acs.jpcc.4c03712","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c03712","url":null,"abstract":"In this work, we employ density functional theory to investigate the electronic structure and optical properties of both Cu-rich Cu_1+<i>x</i>Al_1–<i>x</i>S_2–<i>y</i> bulk and quantum dot (QD) crystals. The copper deep acceptor, which substitutes Al (Cu_Al), is dominant under Cu-rich (Al-poor, S-poor) growth conditions, and in QDs, it may form spontaneously. In the presence of copper at interstitial sites, stable acceptor–donor complexes, such as Cu_Al–2Cu_i and Cu_Al–Cu_i, can be present, which in turn may be a source of p-type conductivity and optical transitions. Cu_Al reveals a tendency toward the formation of aggregates and Cu acceptor pairing that may decrease empty energy levels. The lowering acceptor states may also be induced by the formation of a large broad band above the valence band maximum that stems from the increasing concentration of host Cu atoms. We find that Cu_Al, incorporated in the presence of high concentrations of copper in the host structure, gives rise to photoluminescence (PL) transitions at lower energies, in comparison with PL transitions originating from the impurities in a stochiometric crystal. The effect arises as a result of crystal distortion in the vicinity of the dopant: larger distortions occur in higher Cu/Al ratios and under the surface proximity in QDs as a result of stronger energy relaxations.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron Arrangement and Transfer Regulation of Li2ZrO3 by Metal Doping for Enhanced CO2 Removal at High Temperatures: A Theoretical and Experimental Study","authors":"Yuan Liu, Xingliang Ji, Zhaoyang Zhu, Tao Wang, Jiawei Wang, Yongsheng Zhang, Wei-Ping Pan","doi":"10.1021/acs.jpcc.4c04040","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c04040","url":null,"abstract":"Lithium zirconate (Li₂ZrO₃), as a high-temperature adsorbent with great prospects for development, has a high theoretical adsorption capacity and high recyclability, but it has difficulty achieving the largest possible adsorption capacity with low adsorption rates for practical applications, so the adsorption characteristics of Li₂ZrO₃ are improved by adopting elemental doping methods. Simulation and experimental methods were used to study the influence of K, Na, and Fe adulterating on the adsorption performance of Li₂ZrO₃ and the mechanism of the effect. It is found that the three-element doping can improve the adsorption performance of Li₂ZrO₃, the metal atoms through doping to change the surrounding electron arrangement and thus affect the potential of the surface, to improve the adsorption of CO₂, and to promote the development of surface carbonate species.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Analysis Based on Near-Field Electromagnetic Theory Combined with Molecular Dynamics for Pulse Light-Induced Plasmonic Nanobubble in Gold and Silver Nanofluids","authors":"Qingchun Dong, Wei An","doi":"10.1021/acs.jpcc.4c03473","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c03473","url":null,"abstract":"Noble metallic nanofluids can generate plasmonic nanobubbles (PNB) under short pulse light irradiation. Research of the PNB nucleation energy density threshold (EDT) and its growth kinetics will provide theoretical insights for emerging applications such as optofluidic control and cell-targeted drug delivery. Using a computational model of near-field electromagnetic theory combined with molecular dynamics (MD) simulation, this study compares the EDTs and nucleation times of PNBs around gold and silver nanoparticles (NPs) with different sizes irradiated with 5 and 100 ps pulse lights. Furthermore, it reveals the energy transfer mechanism of the PNB formation and growth by analyzing the temperature evolution of the water layer near the gold and silver NPs. The results show that with the same pulse light duration time and NP size, it is easier for silver NP to generate PNB than gold NP. In addition, PNBs are more likely to form around NPs with larger sizes. However, the impact of the pulse light duration time on PNB formation is more significant than that of the NP material and size. Notably, 6 nm silver NP has a 73% lower EDT with 5 ps pulse light irradiation than 100 ps; furthermore, the nucleation time of PNB is advanced by 77%. The temperature results reveal that the water layer near the silver NPs obtains a higher temperature than that near the gold NPs with 5 ps pulsed light irradiation. The observation indicates that the resonant electric field (REF), induced by a short pulse of light on the gold and silver NP surface, significantly enhances the motion of water molecules. However, under 100 ps pulse light irradiation, the temperatures of gold and silver NPs exceed those of the adjacent water layers. This phenomenon indicates that the thermal diffusion process is significantly slower than the strong effect of the REF on the motion of the water molecules. These results will provide an essential theoretical basis for accurate manipulation of the light and NP parameters to control the formation of PNB.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large Negative-Ion Formation in Grazing Scattering of Neutral Carbon Atoms from a CsI(100) Surface","authors":"Hu Zhou, Yiqing Wang, He Wang, Guangyi Wang, Yuan Li, Dong Feng, Zheyan Tu, Lixun Song, Gang Wu, Qiang Wu, Xin Zhang, Zewen Zong, Zebin Li, Yongtao Zhao, Hongfei Zhang, Ximeng Chen","doi":"10.1021/acs.jpcc.4c05356","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c05356","url":null,"abstract":"Negative ions are crucial in various scientific and technological fields, such as antimatter research, interstellar chemistry, accelerator-based radionuclide dating, fusion injection for controlled nuclear fusion, and neurological disease treatment. Thus, producing a large number of negative ions is highly important. Herein, we present the first theoretical evidence of a large fraction of negative-ion formation during the grazing scattering of carbon atoms from a CsI(100) surface. The conversion efficiency of the negative ions reaches ≥86% within a projectile energy range of <i>E</i>_p ∈ [5,10] keV. These remarkable results are attributed to large anion and cation polarizations, which lead to an evidently large Mott–Littleton polarization interaction. This interaction lowers the energy defect of valence band electron capture to below 1.8 eV near the surface anion sites, drastically increasing the electron-capture probability. The destruction of negative ions occurs owing to affinity electron detachment via the Coulomb barrier tunneling to the vacuum level during the interactions with surface anion sites along their trajectories. Our results indicate that this collision system can be used to design next-generation negative carbon ion sources for studying the isotope shift of electron affinity and provide insights into electron correlation effects and molecular-level irradiation pathological studies, especially for promoting nerve tissue repair and regeneration through <i>E</i>_p ∈ [5,10] keV negative carbon ion irradiation.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142405606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbazole-isonicotinoyl Hydrazone and Its Structurally Distinct Zinc(II) Complexes as Reversible Mechanochromic, Mechanofluorochromic, and Acidochromic Smart Materials","authors":"Himani Sharma, Tarkeshwar Maddeshiya, Mrituanjay D. Pandey, Rampal Pandey","doi":"10.1021/acs.jpcc.4c02928","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c02928","url":null,"abstract":"A new donor–acceptor type hydrazone (<b>HL</b>), namely, (E)-<i>N</i>′-((9-ethyl-9H-carbazol-3-yl)methylene)isonicotinohydrazide comprising carbazole as donor and isonicotinoyl group as acceptor unit and its two Zn(II)-complexes <b>1</b> and <b>2</b> have been synthesized and characterized by elemental analysis, FT-IR, ¹H and ¹³C NMR, and mass spectral techniques. Complexes <b>1</b> and <b>2</b> have been synthesized using the same ligand, <b>HL</b>, and zinc metal ion by treating ZnCl₂ and Zn(NO₃)₂·6H₂O, respectively. The structure of <b>HL</b> was confirmed by single-crystal X-ray diffraction analysis. Comprehensive photophysical properties of <b>HL</b>, <b>1</b>, and <b>2</b> revealed remarkable reversible mechanochromic luminescent behavior of <b>HL</b> and <b>1</b> on grinding, whereas <b>2</b> remains nonresponsive toward mechanical force stimuli. Notably, under UV light irradiation (365 nm), the solid-state emission color of pristine <b>HL</b> changes from blue to yellowish green after grinding, while the luminescence color of <b>1</b> transforms from yellow to orange. In addition, <b>HL</b> and <b>1</b>-<b>2</b> also exhibit acidochromic behavior on exposure to HCl/NH₃ vapors. Notably, the mechanofluorochromism and the acidochromism of <b>HL</b> and <b>1</b> have been thoroughly studied by PXRD, TGA, and DSC studies and fluorescence lifetime measurements. Further, the structural chemistry involved in these behaviors has been thoroughly explored and emphasized that even a small structural variation can significantly alter the photophysical properties of organic and inorganic materials.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142405495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interfacial Strain-Insensitive Thermal and Electrical Stability of (K,Na)NbO3-Based Lead-Free Ferroelectric Films","authors":"Beibei Zhu, Zhengyang Kong, Hexuan Cheng, Kun Han, Pingfan Chen, Ke Wang, Haibo Zhang, Junya Wang, Zhen Huang, Wenbin Wu, Liqiang Xu, Feng Chen","doi":"10.1021/acs.jpcc.4c03280","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c03280","url":null,"abstract":"Despite the inherent strain relaxation in perovskite-type oxide ferroelectric films that occurs beyond a certain thickness, the interfacial states, including carrier and strain, can still influence their electrical properties. This study explores the impact of different (La_0.67,Sr_0.33)MnO₃ (LSMO)-coated perovskite-type oxide substrates on the electrical performance of (K,Na)NbO₃ (KNN)-based ferroelectric films. Specifically, 200 nm-thick epitaxial KNN-based films were grown on four distinct substrates: (001)-oriented KTaO₃, SrTiO₃, LaAlO₃, and YAlO₃. Notably, the lattice constants of the KNN-based films remained unchanged, despite the varying lattice constants of their substrates. The electrical properties of these films were found to be insensitive to the underlying substrate. All films displayed comparable hysteresis loops and frequency-dependent dielectric curves, with a consistent remnant polarization of ∼63 μC/cm² and a dielectric constant of ∼1250 at 1 kHz. Furthermore, the KNN-based films demonstrated exceptional thermal stability. They showed resilience under multiple switching cycles and maintained stable ferroelectricity up to a high temperature of 100 °C. These observations underscore the high electrical and thermal stability of KNN-based ferroelectric films, suggesting their promising potential for applications in electronic devices. This research highlights the robustness and versatility of KNN-based ferroelectric films, which could pave the way for their integration into advanced electronic technologies.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142405496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automatic Identification of X-ray Absorption Fine Structure Spectra via Machine Learning","authors":"Naotoshi Miyasaka, Fernando Gracia-Escobar, Keisuke Takahashi","doi":"10.1021/acs.jpcc.4c02795","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c02795","url":null,"abstract":"X-ray absorption fine structure (XAFS) spectroscopy is a characterization method that can be used to uncover information about the material electronic structure and structural information. XAFS analysis is generally performed by comparing available spectra and relies on experience and knowledge. This work utilizes supervised machine learning with descriptors derived from XAFS and physical quantities of elements to establish an automated and rapid classification method for oxidation states. Two classification methods are explored: a general classification of whether a material is an oxide and a valence number classification. As a result, descriptors and a machine learning model to identify the oxidation states are unveiled where oxidation states are predicted with high accuracy. These results show that the oxide and valence classifications of the target materials can be made with high accuracy from XAFS spectral information according to highly dimensional and complex patterns.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142405493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of Charge Centers in Matter from Geometric Phases of Electrons","authors":"Joyeta Saha, Sujith Nedungattil Subrahmanian, Joydeep Bhattacharjee","doi":"10.1021/acs.jpcc.4c05248","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c05248","url":null,"abstract":"Based on the geometric phases of Bloch electrons, we propose a scheme for the unambiguous spatial partitioning of charge in matter from first-principles, derivable directly from the Kohn–Sham states. Generalizing the fact that geometric phases acquired by electrons, due to the evolution of their crystal momentum &lt;i&gt;&lt;/i&gt;&lt;span style=\"color: inherit;\"&gt;&lt;/span&gt;&lt;span data-mathml='&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;mover&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mo&gt;&amp;#x2192;&lt;/mo&gt;&lt;/mover&gt;&lt;/math&gt;' role=\"presentation\" style=\"position: relative;\" tabindex=\"0\"&gt;&lt;nobr aria-hidden=\"true\"&gt;&lt;span style=\"width: 1.026em; display: inline-block;\"&gt;&lt;span style=\"display: inline-block; position: relative; width: 0.912em; height: 0px; font-size: 110%;\"&gt;&lt;span style=\"position: absolute; clip: rect(0.798em, 1000.86em, 2.332em, -999.997em); top: -2.156em; left: 0em;\"&gt;&lt;span&gt;&lt;span&gt;&lt;span style=\"display: inline-block; position: relative; width: 0.912em; height: 0px;\"&gt;&lt;span style=\"position: absolute; clip: rect(3.128em, 1000.51em, 4.151em, -999.997em); top: -3.974em; left: 0.173em;\"&gt;&lt;span style=\"font-family: STIXMathJax_Normal-italic;\"&gt;𝑘&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 3.98em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"position: absolute; clip: rect(3.355em, 1000.86em, 4.094em, -999.997em); top: -4.713em; left: 0em;\"&gt;&lt;span style=\"\"&gt;&lt;span style=\"font-family: STIXMathJax_Main;\"&gt;→&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 3.98em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 2.162em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; overflow: hidden; vertical-align: -0.059em; border-left: 0px solid; width: 0px; height: 1.441em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;/nobr&gt;&lt;span role=\"presentation\"&gt;&lt;math display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mover&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mo&gt;→&lt;/mo&gt;&lt;/mover&gt;&lt;/math&gt;&lt;/span&gt;&lt;/span&gt;&lt;script type=\"math/mml\"&gt;&lt;math display=\"inline\"&gt;&lt;mover&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mo&gt;→&lt;/mo&gt;&lt;/mover&gt;&lt;/math&gt;&lt;/script&gt; in any arbitrary direction throughout the Brillouin zone (BZ), render the location of their spatial localization with net minimum spread along the direction in real space reciprocal to that of the evolution of &lt;i&gt;&lt;/i&gt;&lt;span style=\"color: inherit;\"&gt;&lt;/span&gt;&lt;span data-mathml='&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;mover&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mo&gt;&amp;#x2192;&lt;/mo&gt;&lt;/mover&gt;&lt;/math&gt;' role=\"presentation\" style=\"position: relative;\" tabindex=\"0\"&gt;&lt;nobr aria-hidden=\"true\"&gt;&lt;span style=\"width: 1.026em; display: inline-block;\"&gt;&lt;span style=\"display: inline-block; position: relative; width: 0.912em; height: 0px; font-size: 110%;\"&gt;&lt;span style=\"position: absolute; clip: rect(0.798em, 1000.86em, 2.332em, -999.997em); top: -2.156em; left: 0em;\"&gt;&lt;span&gt;&lt;span&gt;&lt;span style=\"display: inline-block; position: relative; width: 0.912em; height: 0px;\"&gt;&lt;span style=\"position: absolute; clip: rect(3.128em, 1000.51em, 4.151e","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced Thermodynamic Stability of Delithiated Nano-LiCoO2 by Lanthanum Doping","authors":"Spencer Dahl, Luelc S. Costa, Jefferson Bettini, Flavio L. Souza, Ricardo H. R. Castro","doi":"10.1021/acs.jpcc.4c03415","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c03415","url":null,"abstract":"The dynamic environment within lithium-ion batteries induces significant changes in local thermodynamic functions, hampering the accurate prediction of the stability of the cathodes during cycling. While delithiation primarily affects the surface properties of the cathode structure, there is a lack of fundamental understanding concerning the evolution of interfacial energies with varying stoichiometry. Here, we used microcalorimetry to quantify the thermodynamic changes between the stoichiometric and partially delithiated nano-LiCoO₂ states for the first time. A mild delithiation from LiCoO₂ to Li_0.71CoO₂ caused a surface energy reduction, negatively affecting the adhesion between adjacent grains by ∼0.4J/m². The introduction of lanthanum at 1.0 atom % reduced the surface energy of the stoichiometric LiCoO₂ while forcing a constant surface energy state during delithiation down to Li_0.57CoO₂. This reduced the thermodynamic stress between grains during lithium cycling, mitigating degradation mechanisms. The lanthanum-induced surface stabilization also inhibited the coarsening and dissolution of the cathode particles. We used electron microscopy to propose an atomistic mechanism by which the lanthanum doping pins surface dissolution for improved cathode stability.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dramatic Enhancement of One and Two Photon-Excited Emission of a Stilbazolium Dye Coupled to Laponite Platelets","authors":"Sonal Gupta, Guang S. He, Vivek Kumar, Alec Pitter, Martin Trebbin, Mark T. Swihart, Reshma Kailas Kumar, Leena Nebhani, Yogesh M. Joshi, Richard A. Vaia, Paras N. Prasad","doi":"10.1021/acs.jpcc.4c04198","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c04198","url":null,"abstract":"Natural clays are the oldest example of two-dimensional materials and have been extensively investigated for their structural, morphological, and viscoelastic properties. Although there are reports of optical studies in clay-containing media, clay has traditionally been considered highly scattering, and thus, its optical and nonlinear optical applications have not been extensively examined. Nonlinear optics plays a key role across multiple fields of research and application, including biomedicine, photonics, optoelectronics, and surface science. Nonlinear optical characteristics of two-dimensional materials and of organic–inorganic hybrid materials are of particular interest in recent years. Here, we provide the first demonstration that Laponite, a synthetic clay material, can be a highly promising medium to dramatically enhance the efficiency of emission by both linear and nonlinear excitation of a polar dye, because of its interaction with the ionic microenvironment of Laponite. We show that adsorption of this cationic dye onto the negatively charged faces of Laponite platelets in an aqueous dispersion produces a remarkable enhancement in fluorescence intensity by up to a factor of 15. Notably, the stilbazolium dye exhibits a longer fluorescence lifetime of 480 ps in the presence of Laponite, an order of magnitude longer than that in pure water, revealing that nonradiative processes are slowed via the interaction with Laponite. To probe the origins of this effect, we conducted an array of experiments that investigated the interaction between organic dye and Laponite, including viscosity measurements, ionic conductivity measurements, dynamic light scattering, and small-angle X-ray scattering. These experiments and analysis reveal that modification of the local molecular environment of the dye via interaction with Laponite platelets suppresses nonradiative recombination pathways to dramatically enhance both linear and nonlinear fluorescence in this novel hybrid system. The Laponite dye hybrid displays significant potential for applications in biosensors, optical sensors, fluorescent probes, and other fields, which require high emissive properties.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":null,"pages":null},"PeriodicalIF":4.126,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142398600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}