Accounts of materials research最新文献

{"title":"Unlocking Spin to Boost Thermopower","authors":"Zhongbin Wang, Jiaqing He","doi":"10.1021/accountsmr.4c00310","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00310","url":null,"abstract":"Figure 1. Illustrations of the mechanisms of spin-enhanced charge-based thermopower. (a) Spin entropy: a spin entropy flux is created by differences in spin–orbital degeneracies (<i>g</i>), flowing from high-degeneracy to low-degeneracy states, typically in transition metals (M), contributing to the total thermopower. Additionally, spin entropy arises from disordered spin orientations caused by the breakdown of long-range order at high temperatures, referred to as spin thermodynamic entropy. (b) Spin fluctuation: thermal fluctuations of the local spin density of itinerant electrons are most significant near <i>T</i><sub>C</sub>. These fluctuations are suppressed as the net magnetic moment stabilizes under a strong magnetic field. Reproduced with permission from ref (3). Copyright 2019 The Authors. (c) Magnon drag: magnons propagate in a magnetic material from the hot to the cold end, coupling with both electrons and phonons, contributing to thermopower through momentum transfer. Reproduced with permission from ref (4). Copyright 2021 The Authors. Figure 2. (a) Schematic illustration of spin entropy contributed by the localized electrons on Co ions transfer entropy via hopping transport due to the different degeneracy. Reproduced with permission from ref (6). Copyright 2020 The Authors. (b) The relative change in thermopower of Ca<sub>3</sub>Co<sub>4</sub>O<sub>9+δ</sub> single crystal versus magnetic field for two directions (<i>B</i> along <i>c</i> axis and <i>ab</i> plane). Reproduced with permission from ref (8), Copyright 2013 John Wiley and Sons. (c) Calculated thermopower for different spin states as a function of cobalt valence in the CoO<sub>2</sub> layers. Reproduced with permission from ref (9), Copyright 2012 American Physical Society. (d) Schematic representation of spin orientation and thermodynamic entropy. Reproduced with permission from ref (10). Copyright 2021 The Authors. Figure 3. (a) Temperature dependent on thermopower with and without magnetic field in Fe<sub>2</sub>V<sub>0.9</sub>Cr<sub>0.1</sub>Al<sub>0.9</sub>Si<sub>0.1</sub>. Reproduced with permission from ref (3). Copyright 2019 The Authors.. The inset displays the spin fluctuation contribution peaks at <i>T</i><sub>C</sub>. (b) −<i>S</i>/<i>T</i> of Fe<sub>2</sub>V<sub>0.9</sub>Cr<sub>0.1</sub>Al<sub>0.9</sub>Si<sub>0.1</sub>, plotted as functions of magnetic field and temperature. −<i>S</i>/<i>T</i> has a sharp peak at <i>T</i><sub>C</sub> under zero magnetic field and is significantly suppressed with increasing <i>H</i>. Reproduced with permission from ref (3). Copyright 2019 The Authors. (c) Measured thermopower <i>S</i><sub>total</sub> and magnon drag induced thermopower <i>S</i><sub>M</sub> for Co<sub>2</sub>TiAl. The area between the <i>S</i><sub>total</sub> and <i>S</i><sub>M</sub> lines represents the sum of <i>S</i><sub>sf</sub> and <i>S</i><sub>d</sub>. The inset displays the temperature-dependent thermopower of <i>S</i><sub>sf</sub> + <i>S</i><sub>d</sub> a","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142887164","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":"Unlocking Spin to Boost Thermopower","authors":"Zhongbin Wang,  and , Jiaqing He*, ","doi":"10.1021/accountsmr.4c0031010.1021/accountsmr.4c00310","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00310https://doi.org/10.1021/accountsmr.4c00310","url":null,"abstract":"","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"6 2","pages":"129–135 129–135"},"PeriodicalIF":14.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143507611","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":"Use of Materials Science to Understand Haptic Perception","authors":"Laura L. Becerra, Nicholas B. Root, Robert S. Ramji, Romke Rouw, Darren J. Lipomi","doi":"10.1021/accountsmr.4c00207","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00207","url":null,"abstract":"The haptic sense captures information arising from the somatosensory system─the sensor system of the body excluding the eyes, ears, nose, and tongue. That is, it captures stimuli arising from the skin (i.e., touch) and from internal structures (i.e., the musculoskeletal system and internal organs). The field of research called <i>haptics</i> is concerned with understanding and manipulating this sense, often using engineered technology, and usually for creating novel or realistic touch sensations. Fundamental to every tactile interaction is an interface between the skin and a material. Given that essentially all material objects are composed of or covered in organic media, we reasoned that we, as organic materials scientists, might be able to contribute to the understanding of the sense of touch by manipulating material properties on the molecular scale. Over time, our research group acquired additional skills in electrical engineering and developed strong collaborations with cognitive and behavioral scientists. With a shared curiosity about the sense of touch, we made what we believe are original contributions to the field of haptics.","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142849739","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":"Use of Materials Science to Understand Haptic Perception","authors":"Laura L. Becerra,&nbsp;Nicholas B. Root,&nbsp;Robert S. Ramji,&nbsp;Romke Rouw and Darren J. Lipomi*,&nbsp;","doi":"10.1021/accountsmr.4c0020710.1021/accountsmr.4c00207","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00207https://doi.org/10.1021/accountsmr.4c00207","url":null,"abstract":"&lt;p &gt;The haptic sense captures information arising from the somatosensory system─the sensor system of the body excluding the eyes, ears, nose, and tongue. That is, it captures stimuli arising from the skin (i.e., touch) and from internal structures (i.e., the musculoskeletal system and internal organs). The field of research called &lt;i&gt;haptics&lt;/i&gt; is concerned with understanding and manipulating this sense, often using engineered technology, and usually for creating novel or realistic touch sensations. Fundamental to every tactile interaction is an interface between the skin and a material. Given that essentially all material objects are composed of or covered in organic media, we reasoned that we, as organic materials scientists, might be able to contribute to the understanding of the sense of touch by manipulating material properties on the molecular scale. Over time, our research group acquired additional skills in electrical engineering and developed strong collaborations with cognitive and behavioral scientists. With a shared curiosity about the sense of touch, we made what we believe are original contributions to the field of haptics.&lt;/p&gt;&lt;p &gt;Our approach is guided by a paradigm consisting of four layers from which hypotheses can be generated, experiments can be designed, and whose analytical techniques may be applied. The layers are (1) material composition, (2) material properties, (3) interfacial properties between the skin and the material, and (4) human perception. For example, a material may be composed of one part silicon and two parts oxygen (material composition), which leaves the surface terminated in dipoles and thus a high surface polarizability (material properties). These dipoles may then interact with the skin with a strong van der Waals interaction and high friction (interfacial properties). This friction may lead to stick–slip behavior and could possibly be perceived as fine texture or roughness, even if the surface is smooth (perception).&lt;/p&gt;&lt;p &gt;Another useful organizing principle is that of active vs passive touch. That is, engaging with an object with intent vs having an object brush up against one’s skin without expectation. In either case, the sensation perceived can be described as either fundamental (e.g., roughness, coldness, compliance, and slipperiness) or blended (e.g., wetness). Beginning with an example of how our approach can be used to understand active touch of a blended sensation, we show how polyacrylamide hydrogels can be tuned by adjusting both the mechanical compliance and thermal conductivity to elicit different levels of perceived wetness. We then show how a purpose-designed conductive polymer can render sensations of roughness in the context of a virtual reality simulation that operates by both passive and active modalities. Lastly, we demonstrate a form of haptic “holography” using the photoacoustic effect; that is, π-conjugated materials coated on the skin can render sensations of vibration (perceived","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"6 2","pages":"136–146 136–146"},"PeriodicalIF":14.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143507606","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":"Molecular Acenes for Light Capture, Conversion, and Storage","authors":"Phillip M. Greißel,&nbsp;Anna-Sophie Wollny,&nbsp;Yifan Bo,&nbsp;Dominik Thiel,&nbsp;René Weiß and Dirk M. Guldi*,&nbsp;","doi":"10.1021/accountsmr.4c0030510.1021/accountsmr.4c00305","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00305https://doi.org/10.1021/accountsmr.4c00305","url":null,"abstract":"&lt;p &gt;Efficient photovoltaics (PV) require capturing and converting solar energy across a broad range of energy. Losses due to thermalization and sub-bandgap photons place, however, significant boundaries on the performance of solar cells. For conventional single-junction cells, the theoretical maximum power conversion efficiency is capped at 33%, a constraint known as the detailed balance limit. Realizing the full potential of PVs requires developing novel strategies to overcome this fundamental obstacle. This Account describes the photon-management capabilities of acenes and addresses these fundamental losses en-route toward enhancing PV performances.&lt;/p&gt;&lt;p &gt;For high-energy photons that exceed the semiconductor’s bandgap energy, singlet fission (SF) is a down-conversion pathway to mitigate thermalization losses. SF is a process in organic materials, in which a singlet excited state is split into two independent triplet excited states, effectively doubling the number of charge carriers. Pentacenes stand out among acenes due to their exergonic nature of SF. Numerous molecular pentacene dimers have been synthesized to elucidate the relationship between structure and enhancing SF efficiency.&lt;/p&gt;&lt;p &gt;A broader light-harvesting range of SF materials is realized by covalently attaching complementary absorbing energy donors to set up energy donor–acceptor conjugates. Förster resonance energy transfer (FRET) is operative in these energy donor-acceptor conjugates, effectively extending the absorption of SF materials, as the energy donor efficiently transfers its absorbed excitation energy to the energy acceptor. Our studies on various binding motifs show that FRET efficiency depends not only on parameters like the energy donor–acceptor distance and spectral overlap but also on subtle factors such as the alignment of transition dipoles, which significantly affect the energy transfer dynamics and efficiency.&lt;/p&gt;&lt;p &gt;Turning to low-energy photons, triplet–triplet annihilation up-conversion (TTA-UC) provides a means of light up-conversion and, thereby, the reduction of sub-bandgap losses. In TTA-UC, a singlet excited state that is potent enough to generate charge carriers is formed by combining two triplet excitons. It is effectively the reverse process of SF. The higher triplet energy of tetracene and an endergonic SF renders them highly effective for TTA-UC. We focus on various tetracene-based systems that maximize TTA-UC efficiency.&lt;/p&gt;&lt;p &gt;Besides TTA-UC, two-photon absorption (TPA) is yet another mechanism to leverage below-bandgap photons. It is a nonlinear optical (NLO) process, and acenes reveal NLO properties that are essential for extending light absorption into the near-infrared and still powering SF. We demonstrate in our proof-of-concept studies how TPA further broadens the application potential of acenes for PV systems.&lt;/p&gt;&lt;p &gt;The strategies outlined in this Account illustrate that acenes are valuable for addressing mechanistic losses in conventiona","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"6 2","pages":"172–182 172–182"},"PeriodicalIF":14.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143507607","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":"Molecular Acenes for Light Capture, Conversion, and Storage","authors":"Phillip M. Greißel, Anna-Sophie Wollny, Yifan Bo, Dominik Thiel, René Weiß, Dirk M. Guldi","doi":"10.1021/accountsmr.4c00305","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00305","url":null,"abstract":"Efficient photovoltaics (PV) require capturing and converting solar energy across a broad range of energy. Losses due to thermalization and sub-bandgap photons place, however, significant boundaries on the performance of solar cells. For conventional single-junction cells, the theoretical maximum power conversion efficiency is capped at 33%, a constraint known as the detailed balance limit. Realizing the full potential of PVs requires developing novel strategies to overcome this fundamental obstacle. This Account describes the photon-management capabilities of acenes and addresses these fundamental losses en-route toward enhancing PV performances.","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142849738","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":"Fiber Sorbents – A Versatile Platform for Sorption-Based Gas Separations","authors":"João Marreiros, Yuxiang Wang, MinGyu Song, William J. Koros, Matthew J. Realff, Christopher W. Jones, Ryan P. Lively","doi":"10.1021/accountsmr.4c00201","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00201","url":null,"abstract":"Increasing demand for high-purity fine chemicals and a drive for process intensification of large-scale separations have driven significant work on the development of highly engineered porous materials with promise for sorption-based separations. While sorptive separations in porous materials offer energy-efficient alternatives to longstanding thermal-based methods, the particulate nature of many of these sorbents has sometimes limited their large-scale deployment in high-throughput applications such as gas separations, for which the necessary high feed flow rates and gas velocities accrue prohibitive operational costs.","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142816121","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":"Fiber Sorbents – A Versatile Platform for Sorption-Based Gas Separations","authors":"João Marreiros,&nbsp;Yuxiang Wang,&nbsp;MinGyu Song,&nbsp;William J. Koros,&nbsp;Matthew J. Realff,&nbsp;Christopher W. Jones and Ryan P. Lively*,&nbsp;","doi":"10.1021/accountsmr.4c0020110.1021/accountsmr.4c00201","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00201https://doi.org/10.1021/accountsmr.4c00201","url":null,"abstract":"&lt;p &gt;Increasing demand for high-purity fine chemicals and a drive for process intensification of large-scale separations have driven significant work on the development of highly engineered porous materials with promise for sorption-based separations. While sorptive separations in porous materials offer energy-efficient alternatives to longstanding thermal-based methods, the particulate nature of many of these sorbents has sometimes limited their large-scale deployment in high-throughput applications such as gas separations, for which the necessary high feed flow rates and gas velocities accrue prohibitive operational costs.&lt;/p&gt;&lt;p &gt;These processability limitations have been historically addressed through powder shaping methods aimed at the fabrication of structured sorbent contactors based on pellets, beads or monoliths, commonly obtained as extrudates. These structures overcome limitations such as elevated pressure drops commonly recorded across powder adsorption beds but often accrue thermal limitations arising from elevated particle density and aggregation, which ultimately cap their maximum separation performance. Furthermore, the harsh mechanical strain to which powder particles are subjected during contactor fabrication, in the form of extrusion/compression forces, can result in partial pore occlusion and framework degradation, further limiting their performance.&lt;/p&gt;&lt;p &gt;Here, we present the development of porous fiber sorbents as an alternative sorbent contactor design capable of addressing sorbent processability limitations while enabling an array of performance-maximizing heat integration capabilities. This new sorbent form factor leverages pre-existing know-how from hollow fiber spinning to produce fiber-shaped sorbent contactors through the phase inversion of known polymers in a process known as dry-jet/wet quenching. The process of phase inversion allows microporous sorbent particles to be latched onto a macroporous polymer matrix under mild processing conditions, thus making it compatible with soft porous materials prone to amorphization under traditional pelletization conditions.&lt;/p&gt;&lt;p &gt;Sorbent fibers can be created with different geometries through control of the spinning apparatus and process, offering the possibility to produce monolithic and hollow fibers alike, the latter of which can be integrated with thermalization fluid flows. In this Account, we summarize our progress in the field of fiber sorbents from both design and application standpoints. We further guide the reader through the evolution of this field from the early inceptive work on zeolite hollow fibers to recent developments on MOF fibers. We highlight the versatile nature of fiber sorbents, both from the composition, fabrication and structure points of view, and further demonstrate how fiber sorbents offer alternative paths in tackling new and challenging chemical separation challenges like direct air capture (DAC), with a final perspective on the future of the fiel","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"6 1","pages":"6–16 6–16"},"PeriodicalIF":14.0,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/accountsmr.4c00201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143084232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasmonic Metal Oxide Nanocrystals as Building Blocks for Infrared Metasurfaces","authors":"Woo Je Chang,&nbsp;Allison M. Green,&nbsp;Zarko Sakotic,&nbsp;Daniel Wasserman*,&nbsp;Thomas M. Truskett* and Delia J. Milliron*,&nbsp;","doi":"10.1021/accountsmr.4c0030210.1021/accountsmr.4c00302","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00302https://doi.org/10.1021/accountsmr.4c00302","url":null,"abstract":"&lt;p &gt;Metamaterials operating at infrared (IR) frequencies have garnered significant attention due to the opportunities for resonant interactions with vibrational modes of molecules and materials and manipulation of thermal emission. These metamaterials usually consist of periodic arrangements of subwavelength scale metallic or dielectric elements, patterned either top-down by nanolithographic methods or bottom-up by nanocrystal (NC) assembly. However, conventional metals are inherently constrained by their fixed electron concentrations, which limits the degrees of freedom in the design of the meta-atom unit cells to achieve the desired optical response. In this context, doped metal oxide NCs, with the prototypical case being tin-doped indium oxide (ITO) NCs, are exceptional candidates for self-assembled IR metamaterials, owing to their relatively low and synthetically tunable electron concentrations that govern the frequencies of their IR plasmon resonances. Focusing on ITO NCs as building blocks, this Account describes recent progress in the synthetic tuning of NC optical properties, NC superlattice monolayer preparation methods for fabricating IR resonant metamaterials, and the emerging understanding of the optical response, facilitated by recently developed simulation methods.&lt;/p&gt;&lt;p &gt;Based on experimental and simulation methods we helped develop, we are advancing a mechanistic understanding of how self-assembled NC metamaterials can produce distinctive near- and far-field optical properties not readily achievable in lithographically patterned structures. First, the impacts of the inevitable defects and disorder associated with self-assembly can be rationalized and, in some cases, recognized as advantageous. Second, self-assembly enables intimate nanoscale intermixing of different NC and molecular components. By incorporating probe molecules within the gaps between NCs where the electric field enhancement is the strongest, we show enhanced detection of molecular vibrations that can be optimized by tuning the size and resonance frequency of the NCs. We show how metasurfaces incorporating mixtures of NCs with different doping concentrations can achieve an epsilon-near-zero dielectric response over a broad frequency range. Finally, considering the NC metasurface itself as a building block, we show how photonic structures incorporating these assemblies can harness and amplify their distinctive properties. Through modeling the NC monolayer as a slab with an effective permittivity response, we designed a frequency-tunable IR perfect absorber by layering the NCs on a simple open cavity structure. Since the perfect absorption architecture further enhances the IR electric field localization strength, we expect that this integration strategy can enhance molecular vibration coupling or nonlinear optical response. The versatility of the NC assembly and integration approach suggests opportunities for various metal oxide NC superstructures, including mixing a","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"6 1","pages":"104–113 104–113"},"PeriodicalIF":14.0,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143084648","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":"Plasmonic Metal Oxide Nanocrystals as Building Blocks for Infrared Metasurfaces","authors":"Woo Je Chang, Allison M. Green, Zarko Sakotic, Daniel Wasserman, Thomas M. Truskett, Delia J. Milliron","doi":"10.1021/accountsmr.4c00302","DOIUrl":"https://doi.org/10.1021/accountsmr.4c00302","url":null,"abstract":"Metamaterials operating at infrared (IR) frequencies have garnered significant attention due to the opportunities for resonant interactions with vibrational modes of molecules and materials and manipulation of thermal emission. These metamaterials usually consist of periodic arrangements of subwavelength scale metallic or dielectric elements, patterned either top-down by nanolithographic methods or bottom-up by nanocrystal (NC) assembly. However, conventional metals are inherently constrained by their fixed electron concentrations, which limits the degrees of freedom in the design of the meta-atom unit cells to achieve the desired optical response. In this context, doped metal oxide NCs, with the prototypical case being tin-doped indium oxide (ITO) NCs, are exceptional candidates for self-assembled IR metamaterials, owing to their relatively low and synthetically tunable electron concentrations that govern the frequencies of their IR plasmon resonances. Focusing on ITO NCs as building blocks, this Account describes recent progress in the synthetic tuning of NC optical properties, NC superlattice monolayer preparation methods for fabricating IR resonant metamaterials, and the emerging understanding of the optical response, facilitated by recently developed simulation methods.","PeriodicalId":72040,"journal":{"name":"Accounts of materials research","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142805092","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}