Amjad Al Taleb, Wen Wan, Giorgio Benedek, Miguel M. Ugeda, Daniel Farías
The interplay between substrate interactions and electron–phonon coupling in two-dimensional (2D) materials presents a significant challenge in understanding and controlling their electronic properties. Here, we present a comparative study of the structural characteristics, phonon dynamics, and electron–phonon interactions in bulk and monolayer NbSe2 on epitaxial bilayer graphene (BLG) using helium atom scattering (HAS). High-resolution helium diffraction reveals a (9 × 9)0° superstructure within the NbSe2 monolayer, commensurate with the BLG lattice, while out-of-plane HAS diffraction spectra indicate a low-corrugated (3√3 × 3√3)30° substructure. By monitoring the thermal attenuation of the specular peak across a temperature range of 100 to 300 K, we determined the electron–phonon coupling constant (λHAS) as 0.76 for bulk 2H-NbSe2. In contrast, the NbSe2 monolayer on graphene exhibits a reduced λHAS of 0.55, corresponding to a superconducting critical temperature (TC) of 1.56 K according to the MacMillan formula, consistent with transport measurement findings. Inelastic HAS data provide, besides a set of dispersion curves of acoustic and lower optical phonons, a soft, dispersionless branch of phonons at 1.7 meV, attributed to the interface localized defects distributed with the superstructure period, thus termed Moiré phonons. Our data show that Moiré phonons contribute significantly to the electron–phonon coupling in monolayer NbSe2. These results highlight the crucial role of the BLG in the electron–phonon coupling in monolayer NbSe2, attributed to enhanced charge transfer effects, providing valuable insights into substrate-dependent electronic interactions in 2D superconductors.
{"title":"Electron–Phonon Coupling and Phonon Dynamics in Single-Layer NbSe2 on Graphene: The Role of Moiré Phonons","authors":"Amjad Al Taleb, Wen Wan, Giorgio Benedek, Miguel M. Ugeda, Daniel Farías","doi":"10.1021/acsnano.4c16399","DOIUrl":"https://doi.org/10.1021/acsnano.4c16399","url":null,"abstract":"The interplay between substrate interactions and electron–phonon coupling in two-dimensional (2D) materials presents a significant challenge in understanding and controlling their electronic properties. Here, we present a comparative study of the structural characteristics, phonon dynamics, and electron–phonon interactions in bulk and monolayer NbSe<sub>2</sub> on epitaxial bilayer graphene (BLG) using helium atom scattering (HAS). High-resolution helium diffraction reveals a (9 × 9)0° superstructure within the NbSe<sub>2</sub> monolayer, commensurate with the BLG lattice, while out-of-plane HAS diffraction spectra indicate a low-corrugated (3√3 × 3√3)30° substructure. By monitoring the thermal attenuation of the specular peak across a temperature range of 100 to 300 K, we determined the electron–phonon coupling constant (λ<sub>HAS</sub>) as 0.76 for bulk 2H-NbSe<sub>2</sub>. In contrast, the NbSe<sub>2</sub> monolayer on graphene exhibits a reduced λ<sub>HAS</sub> of 0.55, corresponding to a superconducting critical temperature (<i>T</i><sub>C</sub>) of 1.56 K according to the MacMillan formula, consistent with transport measurement findings. Inelastic HAS data provide, besides a set of dispersion curves of acoustic and lower optical phonons, a soft, dispersionless branch of phonons at 1.7 meV, attributed to the interface localized defects distributed with the superstructure period, thus termed Moiré phonons. Our data show that Moiré phonons contribute significantly to the electron–phonon coupling in monolayer NbSe<sub>2</sub>. These results highlight the crucial role of the BLG in the electron–phonon coupling in monolayer NbSe<sub>2</sub>, attributed to enhanced charge transfer effects, providing valuable insights into substrate-dependent electronic interactions in 2D superconductors.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"28 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Artificial superstructures with advanced physicochemical properties and electronic interfaces are of great importance for capacitive energy storage. Herein, by one-step phase transition and interfacial bridging, we achieve thermodynamically stable synthesis of the 1T-MoS2/graphitic carbon nitride (g-CN) superstructure, where the carbon atoms of g-CN are covalently bridged on molybdenum atoms of the 1T phase molybdenum disulfide (1T-MoS2) interface via C–Mo bonds. The DFT and MD calculations reveal that the 1T-MoS2/g-CN superstructure with a strong interfacial interaction (covalent character: 97%), superior electron conduction (d-band center: −1.2 eV), abundant accessible channels (free volume: 53% whole space), and expedited redox kinetics (reaction energy barriers: 0.9 eV) can enhance interfacial charge transfer and faradaic ion accumulation. Therefore, the 1T-MoS2/g-CN superstructure delivers a high specific capacitance of 2080 F g–1 and excellent structural stability in KOH solution. Moreover, the solid–polymer–electrolyte chip-based 1T-MoS2/g-CN supercapacitors can achieve a large energy density (73 mWh g–1), outstanding cycling stability (91% capacitance retention after 10,000 cycles), and desired self-powered application.
{"title":"Thermodynamically Stable Synthesis of the 1T-MoS2/g-CN Superstructure with Rapid Redox Kinetics for Robust Capacitive Energy Storage","authors":"Xingjiang Wu, Xude Yu, Zhicheng Tian, Hao Li, Jianhong Xu","doi":"10.1021/acsnano.5c00717","DOIUrl":"https://doi.org/10.1021/acsnano.5c00717","url":null,"abstract":"Artificial superstructures with advanced physicochemical properties and electronic interfaces are of great importance for capacitive energy storage. Herein, by one-step phase transition and interfacial bridging, we achieve thermodynamically stable synthesis of the 1T-MoS<sub>2</sub>/graphitic carbon nitride (g-CN) superstructure, where the carbon atoms of g-CN are covalently bridged on molybdenum atoms of the 1T phase molybdenum disulfide (1T-MoS<sub>2</sub>) interface via C–Mo bonds. The DFT and MD calculations reveal that the 1T-MoS<sub>2</sub>/g-CN superstructure with a strong interfacial interaction (covalent character: 97%), superior electron conduction (d-band center: −1.2 eV), abundant accessible channels (free volume: 53% whole space), and expedited redox kinetics (reaction energy barriers: 0.9 eV) can enhance interfacial charge transfer and faradaic ion accumulation. Therefore, the 1T-MoS<sub>2</sub>/g-CN superstructure delivers a high specific capacitance of 2080 F g<sup>–1</sup> and excellent structural stability in KOH solution. Moreover, the solid–polymer–electrolyte chip-based 1T-MoS<sub>2</sub>/g-CN supercapacitors can achieve a large energy density (73 mWh g<sup>–1</sup>), outstanding cycling stability (91% capacitance retention after 10,000 cycles), and desired self-powered application.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"40 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Iron metabolism of neutrophils plays a vital role in neutrophil extracellular trap (NET) formation, which presents as one of the major hurdles to the immune response in the tumor microenvironment. Here, we developed a peptide–drug conjugate (PDC)-based transformable iron nanochelator (TIN) equipped with the ability to regulate the iron metabolism of neutrophils, endowing inhibition of NET formation and the ensuing immunosuppression functions. The TIN could expose the iron-binding motifs through neutrophil elastase-mediated morphological transformation from nanoparticles to β-sheet nanofibers, which further evolve into stable α-helix nanofibers after chelation with iron(II) ions. This process enables a highly specific regulation of iron(II) ions of neutrophils, which turns into an efficient way of inhibiting NET formation and improving the immune response. Furthermore, the TIN showed an improved therapeutic effect in combination with protein arginine deiminase 4 inhibitors and synergistically boosted the anti-PD-L1 treatment. This study designates an iron-regulation strategy to inhibit NET formation, which provides an alternative approach to immune modulation from the perspective of targeting the iron metabolism of neutrophils in cancer immunotherapy.
{"title":"Inhibiting Neutrophil Extracellular Trap Formation through Iron Regulation for Enhanced Cancer Immunotherapy","authors":"Jinmin Ye, Yatong Qin, Hui Liu, Hehe Xiong, Heng Zhang, Huaxiang Shen, Fantian Zeng, Changrong Shi, Zijian Zhou","doi":"10.1021/acsnano.4c18555","DOIUrl":"https://doi.org/10.1021/acsnano.4c18555","url":null,"abstract":"Iron metabolism of neutrophils plays a vital role in neutrophil extracellular trap (NET) formation, which presents as one of the major hurdles to the immune response in the tumor microenvironment. Here, we developed a peptide–drug conjugate (PDC)-based transformable iron nanochelator (TIN) equipped with the ability to regulate the iron metabolism of neutrophils, endowing inhibition of NET formation and the ensuing immunosuppression functions. The TIN could expose the iron-binding motifs through neutrophil elastase-mediated morphological transformation from nanoparticles to β-sheet nanofibers, which further evolve into stable α-helix nanofibers after chelation with iron(II) ions. This process enables a highly specific regulation of iron(II) ions of neutrophils, which turns into an efficient way of inhibiting NET formation and improving the immune response. Furthermore, the TIN showed an improved therapeutic effect in combination with protein arginine deiminase 4 inhibitors and synergistically boosted the anti-PD-L1 treatment. This study designates an iron-regulation strategy to inhibit NET formation, which provides an alternative approach to immune modulation from the perspective of targeting the iron metabolism of neutrophils in cancer immunotherapy.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"2 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Di Tan, Bo Zhu, Kangjian Xiao, Lijun Li, Zhekun Shi, Quan Liu, Stanislav Gorb, Huajian Gao, Jonathan T. Pham, Ze Liu, Longjian Xue
The nanocapillary not only contributes to the wet adhesion generated from microscale setae on the feet of many insects, such as beetles and flies, but also plays a critical role in many different fields of science and engineering like nanofabrication, chemical analysis, etc. In spite of long-standing interests and efforts, the exact physical mechanisms of nanoscale capillarity remain unclear. Here, we establish a setae-mimicking artificial system composed of porous nanorod arrays (PNAs), where the dynamic process of wet adhesion can be clearly monitored and revealed, when mineral oil is dynamically transferred to the interface between the tips of PNAs and the contacting surface. The large curvature associated with the nanosize of PNA tips endows three advantages to the insect-inspired wet adhesion: (1) shortening the time required to form stable liquid bridges, (2) enhancing the adhesion strength by 6–10 times, and (3) saving at least half of the secretions after detachment. Extra Laplace pressure and line tension originated from the nanocurved liquid at the PNA tips are responsible for the faster, stronger, and liquid-saving wet adhesion. These findings not only strengthen our understanding of the dynamic capillary effects in insect adhesion but may also offer design strategies in nanoprinting, nanorobots, and self-assembly of nanodevices.
{"title":"Nanosized Contact Enables Faster, Stronger, and Liquid-Saving Capillary Adhesion","authors":"Di Tan, Bo Zhu, Kangjian Xiao, Lijun Li, Zhekun Shi, Quan Liu, Stanislav Gorb, Huajian Gao, Jonathan T. Pham, Ze Liu, Longjian Xue","doi":"10.1021/acsnano.4c14048","DOIUrl":"https://doi.org/10.1021/acsnano.4c14048","url":null,"abstract":"The nanocapillary not only contributes to the wet adhesion generated from microscale setae on the feet of many insects, such as beetles and flies, but also plays a critical role in many different fields of science and engineering like nanofabrication, chemical analysis, etc. In spite of long-standing interests and efforts, the exact physical mechanisms of nanoscale capillarity remain unclear. Here, we establish a setae-mimicking artificial system composed of porous nanorod arrays (PNAs), where the dynamic process of wet adhesion can be clearly monitored and revealed, when mineral oil is dynamically transferred to the interface between the tips of PNAs and the contacting surface. The large curvature associated with the nanosize of PNA tips endows three advantages to the insect-inspired wet adhesion: (1) shortening the time required to form stable liquid bridges, (2) enhancing the adhesion strength by 6–10 times, and (3) saving at least half of the secretions after detachment. Extra Laplace pressure and line tension originated from the nanocurved liquid at the PNA tips are responsible for the faster, stronger, and liquid-saving wet adhesion. These findings not only strengthen our understanding of the dynamic capillary effects in insect adhesion but may also offer design strategies in nanoprinting, nanorobots, and self-assembly of nanodevices.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"28 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gaurav R. Dey, Haley L. Young, Simeon Teklu, Samuel S. Soliman, Raymond E. Schaak
The growth of inorganic shells on nanocrystal seeds to form core@shell nanoparticles is well-known to enhance and improve properties and performance, and therefore is foundational to many applications. High entropy alloys, which contain five or more metals in near-equal amounts, are emerging as important materials due to their synergistic properties. Integrating high entropy alloys into the shells of core@shell nanoparticles has the potential to combine and expand the benefits of both. However, the compositional complexity of high entropy alloys complicates shell growth because of the many competing reactions and byproducts that are possible. Here, we report a synthetic protocol for growing high entropy alloy shells on metal nanoparticle seeds, along with mechanistic insights from time-point studies that define guidelines for controlling core@shell nanoparticle composition, thickness, and growth modes. By studying the growth of NiPdPtRhIr, SnPdPtRhIr, and SnNiPdPtIr shells on Au seeds and NiFePdRhIr shells on both Au and Pt seeds, we find that the seed modifies the reaction pathways and accelerates the formation of high entropy alloys compared to when they are synthesized directly in the absence of a seed. We also identify competing reactions that produce freestanding multimetallic particles instead of the desired high entropy alloy shells, as well as evidence for galvanic exchange and ripening processes that contribute to shell growth. Based on these insights, we compiled a synthetic roadmap of design rules that was then applied to the design and synthesis of additional high entropy alloy shells, including SnNiFeRhIr and SnNiFeCoPd, that expand compositional tolerance relative to what can be achieved through direct synthesis.
{"title":"Influence of Nanoparticle Seeds on the Formation and Growth of High Entropy Alloys during Core@Shell Nanoparticle Synthesis","authors":"Gaurav R. Dey, Haley L. Young, Simeon Teklu, Samuel S. Soliman, Raymond E. Schaak","doi":"10.1021/acsnano.4c16417","DOIUrl":"https://doi.org/10.1021/acsnano.4c16417","url":null,"abstract":"The growth of inorganic shells on nanocrystal seeds to form core@shell nanoparticles is well-known to enhance and improve properties and performance, and therefore is foundational to many applications. High entropy alloys, which contain five or more metals in near-equal amounts, are emerging as important materials due to their synergistic properties. Integrating high entropy alloys into the shells of core@shell nanoparticles has the potential to combine and expand the benefits of both. However, the compositional complexity of high entropy alloys complicates shell growth because of the many competing reactions and byproducts that are possible. Here, we report a synthetic protocol for growing high entropy alloy shells on metal nanoparticle seeds, along with mechanistic insights from time-point studies that define guidelines for controlling core@shell nanoparticle composition, thickness, and growth modes. By studying the growth of NiPdPtRhIr, SnPdPtRhIr, and SnNiPdPtIr shells on Au seeds and NiFePdRhIr shells on both Au and Pt seeds, we find that the seed modifies the reaction pathways and accelerates the formation of high entropy alloys compared to when they are synthesized directly in the absence of a seed. We also identify competing reactions that produce freestanding multimetallic particles instead of the desired high entropy alloy shells, as well as evidence for galvanic exchange and ripening processes that contribute to shell growth. Based on these insights, we compiled a synthetic roadmap of design rules that was then applied to the design and synthesis of additional high entropy alloy shells, including SnNiFeRhIr and SnNiFeCoPd, that expand compositional tolerance relative to what can be achieved through direct synthesis.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"26 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zachary R. Lawson, Luca Ciambriello, Brendan D. Nieukirk, John Howe, Runze Tang, Irvin A. Servin, Luca Gavioli, Robert A. Hughes, Svetlana Neretina
The plasmon-mediated growth of noble metal nanoplates through the reduction of metal precursors onto resonantly excited seeds lined with planar defects stands out as one of the triumphs of photochemistry and nanometal synthesis. Such growth modes are, however, not without their drawbacks and, with a lack of suitable alternatives, limitations remain on the use of light as a synthetic control. Herein, a two-reagent seed-mediated gold nanoplate synthesis is demonstrated as a photochemical pathway where the illumination of the growth solution, as opposed to the emerging nanoplates, is the key requirement for growth. With long-lived reaction products, it becomes possible to optically prime the growth solution prior to the insertion of substrate-immobilized seeds and then carry out a seemingly paradoxical synthesis in which light-mediated growth occurs in total darkness. The redox chemistry responsible for nanoplate growth can be induced either through the direct optical excitation of the growth solution using short-wavelength visible light or at longer wavelengths through the plasmonic excitation of spherical colloidal gold nanoparticles added to the growth solution. With the former acting as a high-level wavelength-dependent control over nanoplate synthesis and the latter demonstrating plasmon-mediated metal deposition that is spatially and temporally isolated from the resonant excitation, the study forwards the use of light as an external driver for nanostructure synthesis.
{"title":"Light-Mediated Growth of Gold Nanoplates Carried Out in Total Darkness","authors":"Zachary R. Lawson, Luca Ciambriello, Brendan D. Nieukirk, John Howe, Runze Tang, Irvin A. Servin, Luca Gavioli, Robert A. Hughes, Svetlana Neretina","doi":"10.1021/acsnano.5c01191","DOIUrl":"https://doi.org/10.1021/acsnano.5c01191","url":null,"abstract":"The plasmon-mediated growth of noble metal nanoplates through the reduction of metal precursors onto resonantly excited seeds lined with planar defects stands out as one of the triumphs of photochemistry and nanometal synthesis. Such growth modes are, however, not without their drawbacks and, with a lack of suitable alternatives, limitations remain on the use of light as a synthetic control. Herein, a two-reagent seed-mediated gold nanoplate synthesis is demonstrated as a photochemical pathway where the illumination of the growth solution, as opposed to the emerging nanoplates, is the key requirement for growth. With long-lived reaction products, it becomes possible to optically prime the growth solution prior to the insertion of substrate-immobilized seeds and then carry out a seemingly paradoxical synthesis in which light-mediated growth occurs in total darkness. The redox chemistry responsible for nanoplate growth can be induced either through the direct optical excitation of the growth solution using short-wavelength visible light or at longer wavelengths through the plasmonic excitation of spherical colloidal gold nanoparticles added to the growth solution. With the former acting as a high-level wavelength-dependent control over nanoplate synthesis and the latter demonstrating plasmon-mediated metal deposition that is spatially and temporally isolated from the resonant excitation, the study forwards the use of light as an external driver for nanostructure synthesis.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"1 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhipeng Li, Huimin Mao, Xiaobin Liu, Jun Wan, Jingqi Chi, Shaobo Huang, Qingliang Lv, Zexing Wu, Lei Wang
During seawater electrolysis, chloride ion (Cl–) adsorption at the anode leads to an inevitable competitive chloride oxidation reaction (ClOR) with the oxygen evolution reaction (OER), compromising the long-term stability of the electrolysis process. Furthermore, Ni-based OER electrocatalysts are challenged by activity degradation due to the overoxidation of Ni3+. In response, we present a design of oxygen-vacancy-regulated asymmetric Nb–O–Ni bonds aimed at selective seawater oxidation. The experimental and in situ characterization results indicate that the blocking effect of oxygen vacancies effectively alleviates the electron release of Ni3+ and the electron enrichment of Nb5+ on asymmetric Nb–O–Ni bonds, achieving a stable and selective OER in alkaline seawater. Density functional theory (DFT) calculations reveal that oxygen vacancies in Nb–O–Ni bonds optimize the adsorption strength of reaction intermediates and break up the scaling relationship between *OH and *OOH intermediates. The constructed anion exchange membrane electrolysis cell achieves a cost efficiency of $1.07 per GGE (gasoline gallon equivalent) for H2 production at a current density of 1000 mA cm–2, maintaining operational stability for 100 h at 500 mA cm–2.
{"title":"Blocking Effect Retards Electron Release from Asymmetric Active Units for Selective Seawater Oxidation","authors":"Zhipeng Li, Huimin Mao, Xiaobin Liu, Jun Wan, Jingqi Chi, Shaobo Huang, Qingliang Lv, Zexing Wu, Lei Wang","doi":"10.1021/acsnano.4c17958","DOIUrl":"https://doi.org/10.1021/acsnano.4c17958","url":null,"abstract":"During seawater electrolysis, chloride ion (Cl<sup>–</sup>) adsorption at the anode leads to an inevitable competitive chloride oxidation reaction (ClOR) with the oxygen evolution reaction (OER), compromising the long-term stability of the electrolysis process. Furthermore, Ni-based OER electrocatalysts are challenged by activity degradation due to the overoxidation of Ni<sup>3+</sup>. In response, we present a design of oxygen-vacancy-regulated asymmetric Nb–O–Ni bonds aimed at selective seawater oxidation. The experimental and in situ characterization results indicate that the blocking effect of oxygen vacancies effectively alleviates the electron release of Ni<sup>3+</sup> and the electron enrichment of Nb<sup>5+</sup> on asymmetric Nb–O–Ni bonds, achieving a stable and selective OER in alkaline seawater. Density functional theory (DFT) calculations reveal that oxygen vacancies in Nb–O–Ni bonds optimize the adsorption strength of reaction intermediates and break up the scaling relationship between *OH and *OOH intermediates. The constructed anion exchange membrane electrolysis cell achieves a cost efficiency of $1.07 per GGE (gasoline gallon equivalent) for H<sub>2</sub> production at a current density of 1000 mA cm<sup>–2</sup>, maintaining operational stability for 100 h at 500 mA cm<sup>–2</sup>.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"51 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Efficient catalysis of intermediate lithium polysulfide (LiPS) conversion in lithium–sulfur batteries is crucial for enhancing sulfur reduction reaction (SRR) kinetics and suppressing the shuttle effect of LiPSs. High-entropy alloys (HEAs), with their compositional flexibility, structural diversity, and multielement synergy, are promising high-efficiency catalyst candidates. Herein, a work function-dominated d-band center rule is proposed to modulate the chemical absorption ability of LiPSs and the catalytic performance of HEA catalysts. The d-band center of the as-screened PtCuFeCoNi HEAs (PCFCN–HEAs) is modulated via distinct work functions of its five metallic elements. In addition, detailed density functional theory (DFT) calculations and X-ray absorption spectroscopy are performed to reveal the roles of individual metallic elements in HEAs. Optimizing the d-band center of PCFCN–HEAs notably enhances the adsorption of LiPSs and accelerates the SRR. PCFCN–HEA nanoparticles are deposited on the surface of hollow carbon spheres (HCSs) and they combine with hyphae carbon nanobelts (HCNBs) to form a PCFCN–HEA/HCS/HCNB composite as the sulfur host. The cathode with PCNFC-HEA catalyst exhibits stable cycling at 6C and delivers a high reversible capacity of 652 mAh g–1 even at a high rate of 8C. DFT calculations further elucidate the stepwise catalytic mechanism of PCFCN–HEAs, offering a pathway for designing high-efficiency catalysts.
{"title":"High Rate and Long-Cycle Life of Lithium–Sulfur Battery Enabled by High d-Band Center of High-Entropy Alloys","authors":"Fengfeng Han, Lirong Zhang, Qi Jin, Xinzhi Ma, Zhiguo Zhang, Zhenhua Sun, Xitian Zhang, Lili Wu","doi":"10.1021/acsnano.4c18642","DOIUrl":"https://doi.org/10.1021/acsnano.4c18642","url":null,"abstract":"Efficient catalysis of intermediate lithium polysulfide (LiPS) conversion in lithium–sulfur batteries is crucial for enhancing sulfur reduction reaction (SRR) kinetics and suppressing the shuttle effect of LiPSs. High-entropy alloys (HEAs), with their compositional flexibility, structural diversity, and multielement synergy, are promising high-efficiency catalyst candidates. Herein, a work function-dominated d-band center rule is proposed to modulate the chemical absorption ability of LiPSs and the catalytic performance of HEA catalysts. The d-band center of the as-screened PtCuFeCoNi HEAs (PCFCN–HEAs) is modulated via distinct work functions of its five metallic elements. In addition, detailed density functional theory (DFT) calculations and X-ray absorption spectroscopy are performed to reveal the roles of individual metallic elements in HEAs. Optimizing the d-band center of PCFCN–HEAs notably enhances the adsorption of LiPSs and accelerates the SRR. PCFCN–HEA nanoparticles are deposited on the surface of hollow carbon spheres (HCSs) and they combine with hyphae carbon nanobelts (HCNBs) to form a PCFCN–HEA/HCS/HCNB composite as the sulfur host. The cathode with PCNFC-HEA catalyst exhibits stable cycling at 6C and delivers a high reversible capacity of 652 mAh g<sup>–1</sup> even at a high rate of 8C. DFT calculations further elucidate the stepwise catalytic mechanism of PCFCN–HEAs, offering a pathway for designing high-efficiency catalysts.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"15 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Telecom-band waveguide photodetectors have revealed great potential for optical communication, computing, and light detection and ranging. Traditional silicon-based waveguide photodetectors based on bulk materials suffer from lattice and thermal expansion coefficient mismatch, resulting in the degradation of device performance. Recently, two-dimensional MoTe2 has become an attractive candidate for waveguide photodetectors due to the absence of dangling bonds and strong light-matter interaction. However, the large bandgap and low carrier mobility of MoTe2 pose an obstacle to achieving high responsivity and large bandwidth in the telecom band. Here, we demonstrate a high-speed and high-responsivity vertical graphene-MoTe2-graphene heterostructure photodetector. Benefiting from the strain-induced bandgap manipulation, the device exhibits a high responsivity of 20 mA W–1 in the telecom C-band (∼1550 nm) and a record-high responsivity of 567 mA W–1 in the telecom O-band (∼1310 nm). On the other hand, the vertical heterostructure minimizes the carrier transit path and promises a high 3 dB bandwidth of 4.81 GHz. Thanks to the comprehensive engineering of the band gap and carrier transition, the demonstrated device achieves a record-high responsivity-bandwidth product. This work demonstrates a high-responsivity and high-speed MoTe2 photodetector for telecom-band applications.
{"title":"High-Speed and High-Responsivity Vertical van der Waals Heterostructure Waveguide Photodetector Operating in Telecom Band","authors":"Changming Yang, Zeyi Liu, Hongjun Cai, Dehui Li, Yu Yu, Xinliang Zhang","doi":"10.1021/acsnano.4c14937","DOIUrl":"https://doi.org/10.1021/acsnano.4c14937","url":null,"abstract":"Telecom-band waveguide photodetectors have revealed great potential for optical communication, computing, and light detection and ranging. Traditional silicon-based waveguide photodetectors based on bulk materials suffer from lattice and thermal expansion coefficient mismatch, resulting in the degradation of device performance. Recently, two-dimensional MoTe<sub>2</sub> has become an attractive candidate for waveguide photodetectors due to the absence of dangling bonds and strong light-matter interaction. However, the large bandgap and low carrier mobility of MoTe<sub>2</sub> pose an obstacle to achieving high responsivity and large bandwidth in the telecom band. Here, we demonstrate a high-speed and high-responsivity vertical graphene-MoTe<sub>2</sub>-graphene heterostructure photodetector. Benefiting from the strain-induced bandgap manipulation, the device exhibits a high responsivity of 20 mA W<sup>–1</sup> in the telecom C-band (∼1550 nm) and a record-high responsivity of 567 mA W<sup>–1</sup> in the telecom O-band (∼1310 nm). On the other hand, the vertical heterostructure minimizes the carrier transit path and promises a high 3 dB bandwidth of 4.81 GHz. Thanks to the comprehensive engineering of the band gap and carrier transition, the demonstrated device achieves a record-high responsivity-bandwidth product. This work demonstrates a high-responsivity and high-speed MoTe<sub>2</sub> photodetector for telecom-band applications.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"192 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The recent emergence of self-driving laboratories (SDL) and material acceleration platforms (MAPs) demonstrates the ability of these systems to change the way chemistry and material syntheses will be performed in the future. Especially in conjunction with nano- and advanced materials which are generally recognized for their great potential in solving current material science challenges, such systems can make disrupting contributions. Here, we describe in detail MINERVA, an SDL specifically built and designed for the synthesis, purification, and in line characterization of nano- and advanced materials. By fully automating these three process steps for seven different materials from five representative, completely different classes of nano- and advanced materials (metal, metal oxide, silica, metal organic framework, and core–shell particles) that follow different reaction mechanisms, we demonstrate the great versatility and flexibility of the platform. We further study the reproducibility and particle size distributions of these seven representative materials in depth and show the excellent performance of the platform when synthesizing these material classes. Lastly, we discuss the design considerations as well as the hardware and software components that went into building the platform and make all of the components publicly available.
{"title":"A Self-Driving Lab for Nano- and Advanced Materials Synthesis","authors":"Mohammad Zaki, Carsten Prinz, Bastian Ruehle","doi":"10.1021/acsnano.4c17504","DOIUrl":"https://doi.org/10.1021/acsnano.4c17504","url":null,"abstract":"The recent emergence of self-driving laboratories (SDL) and material acceleration platforms (MAPs) demonstrates the ability of these systems to change the way chemistry and material syntheses will be performed in the future. Especially in conjunction with nano- and advanced materials which are generally recognized for their great potential in solving current material science challenges, such systems can make disrupting contributions. Here, we describe in detail MINERVA, an SDL specifically built and designed for the synthesis, purification, and in line characterization of nano- and advanced materials. By fully automating these three process steps for seven different materials from five representative, completely different classes of nano- and advanced materials (metal, metal oxide, silica, metal organic framework, and core–shell particles) that follow different reaction mechanisms, we demonstrate the great versatility and flexibility of the platform. We further study the reproducibility and particle size distributions of these seven representative materials in depth and show the excellent performance of the platform when synthesizing these material classes. Lastly, we discuss the design considerations as well as the hardware and software components that went into building the platform and make all of the components publicly available.","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":"53 1","pages":""},"PeriodicalIF":17.1,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143486448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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