Surface chemistry dictates the optoelectronic properties of semiconductor quantum dots (QDs). Tailoring these properties relies on meticulous selection of surface ligand for efficient passivation. While long-chain organic ligands boast a well-understood passivation mechanism, the intricacies of short inorganic ionic ligands remain largely unexplored. This study sheds light on the surface-passivation mechanism of short inorganic ligands, particularly focusing on SCN- ions on CdSe QDs. Employing steady state and time-resolved infrared spectroscopies, we elucidate the surface-ligand interactions and coordination modes of SCN--capped CdSe QDs. Comparative analysis with studies on CdS QDs unveils intriguing insights into the coordination behavior and passivation efficacy of SCN- ions on Cd2+ rich QD surfaces. Our results reveal the requirement of both surface-bound (strong binding) and weakly-interacting interfacial SCN- ions for effective CdSe QD passivation. Beyond fostering a deeper understanding of surface-ligand interactions and highlighting the importance for a comprehensive exploration of ligand chemistries, this study holds implications for optimizing QD performance across diverse applications.
{"title":"Probing Surface Interactions in CdSe Quantum Dots with Thiocyanate Ligands","authors":"Samadhan H. Deshmukh, Sushma Yadav, Tubai Chowdhury, Akhil Pathania, Sameer Sapra, Sayan Bagchi","doi":"10.1039/d4nr01507j","DOIUrl":"https://doi.org/10.1039/d4nr01507j","url":null,"abstract":"Surface chemistry dictates the optoelectronic properties of semiconductor quantum dots (QDs). Tailoring these properties relies on meticulous selection of surface ligand for efficient passivation. While long-chain organic ligands boast a well-understood passivation mechanism, the intricacies of short inorganic ionic ligands remain largely unexplored. This study sheds light on the surface-passivation mechanism of short inorganic ligands, particularly focusing on SCN- ions on CdSe QDs. Employing steady state and time-resolved infrared spectroscopies, we elucidate the surface-ligand interactions and coordination modes of SCN--capped CdSe QDs. Comparative analysis with studies on CdS QDs unveils intriguing insights into the coordination behavior and passivation efficacy of SCN- ions on Cd2+ rich QD surfaces. Our results reveal the requirement of both surface-bound (strong binding) and weakly-interacting interfacial SCN- ions for effective CdSe QD passivation. Beyond fostering a deeper understanding of surface-ligand interactions and highlighting the importance for a comprehensive exploration of ligand chemistries, this study holds implications for optimizing QD performance across diverse applications.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stokes’ law with stick boundary condition has been widely accepted for the transport of microscale particles in a liquid. For nanoparticles, however, the hydrodynamic boundary conditions become unclear. In this work, the drag force acting on nanoparticles suspended in a liquid and the hydrodynamic boundary coefficient are calculated by using molecular dynamics simulations. For weak interfacial couplings, slip boundary condition can be used to describe the particle transport, whereas at strong interfacial couplings, the hydrodynamic boundary coefficient converges to a value greater than the prediction by the Stokes’ law. In the present paper, we propose a density accumulation length to determine the effective particle size, which makes Stokes’ law valid for nanoparticles. For a copper nanoparticle suspended in an argon liquid, the density accumulation length increases to 0.32 nm with increasing solid-liquid coupling strength. Furthermore, it is found that there exists a transition from slip to stick boundary conditions as the solid-liquid intermolecular coupling strength increases. The results presented in this work provide guidance for the prediction and manipulation of the transport properties of nanoparticles in a liquid.
{"title":"Drag on nanoparticles in a liquid：from slip to stick boundary conditions","authors":"Wangwang Liu, Jun Wang, Guodong Xia, Zhigang Li","doi":"10.1039/d4nr01379d","DOIUrl":"https://doi.org/10.1039/d4nr01379d","url":null,"abstract":"Stokes’ law with stick boundary condition has been widely accepted for the transport of microscale particles in a liquid. For nanoparticles, however, the hydrodynamic boundary conditions become unclear. In this work, the drag force acting on nanoparticles suspended in a liquid and the hydrodynamic boundary coefficient are calculated by using molecular dynamics simulations. For weak interfacial couplings, slip boundary condition can be used to describe the particle transport, whereas at strong interfacial couplings, the hydrodynamic boundary coefficient converges to a value greater than the prediction by the Stokes’ law. In the present paper, we propose a density accumulation length to determine the effective particle size, which makes Stokes’ law valid for nanoparticles. For a copper nanoparticle suspended in an argon liquid, the density accumulation length increases to 0.32 nm with increasing solid-liquid coupling strength. Furthermore, it is found that there exists a transition from slip to stick boundary conditions as the solid-liquid intermolecular coupling strength increases. The results presented in this work provide guidance for the prediction and manipulation of the transport properties of nanoparticles in a liquid.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel Dyer, Stephen Church, Rubén Ahumada-Lazo, Menno Kappers, Matthew Halsall, Patrick Parkinson, David J. Wallis, Rachel Oliver, David Binks
The decrease in emission efficiency with increasing drive current density, known as ‘droop’, of c-plane wurtzite InGaN/GaN quantum wells presently limits the use of light-emitting diodes based on them for high brightness lighting applications. InGaN/GaN quantum wells grown in the alternative zincblende phase are free of the strong polarisation fields that exacerbate droop and so were investigated by excitation-dependent photoluminescence and photoreflectance studies. Polarisation-resolved measurements revealed that for all excitation densities studied the emission from such samples largely originates from similar microstructures or combinations of microstructures that form within the quantum well layers. Emission efficiency varies significantly with excitation at 10K showing that non-radiative recombination processes are important even at low temperature. The onset of efficiency droop, as determined by photomodulated reflection measurements, occurred at a carrier density of around 1.2×1020 cm−3 - an order of magnitude greater than the value reported for a reference wurtzite quantum well sample using the same method. The high carrier density droop onset combined with the much shorter carrier lifetime within zincblende InGaN/GaN quantum wells indicate they have the potential to effectively delay efficiency droop when used in GaN based light-emitting diodes. However, the material quality of the quantum well layers need to be improved by preventing the formation of microstructures within these layers, and the importance of the role played by non-radiative centres in the QW layer needs to be elucidated, to fully realise the materials potential.
{"title":"Efficiency Droop in Zincblende InGaN/GaN Quantum Wells","authors":"Daniel Dyer, Stephen Church, Rubén Ahumada-Lazo, Menno Kappers, Matthew Halsall, Patrick Parkinson, David J. Wallis, Rachel Oliver, David Binks","doi":"10.1039/d4nr00812j","DOIUrl":"https://doi.org/10.1039/d4nr00812j","url":null,"abstract":"The decrease in emission efficiency with increasing drive current density, known as ‘droop’, of c-plane wurtzite InGaN/GaN quantum wells presently limits the use of light-emitting diodes based on them for high brightness lighting applications. InGaN/GaN quantum wells grown in the alternative zincblende phase are free of the strong polarisation fields that exacerbate droop and so were investigated by excitation-dependent photoluminescence and photoreflectance studies. Polarisation-resolved measurements revealed that for all excitation densities studied the emission from such samples largely originates from similar microstructures or combinations of microstructures that form within the quantum well layers. Emission efficiency varies significantly with excitation at 10K showing that non-radiative recombination processes are important even at low temperature. The onset of efficiency droop, as determined by photomodulated reflection measurements, occurred at a carrier density of around 1.2×1020 cm−3 - an order of magnitude greater than the value reported for a reference wurtzite quantum well sample using the same method. The high carrier density droop onset combined with the much shorter carrier lifetime within zincblende InGaN/GaN quantum wells indicate they have the potential to effectively delay efficiency droop when used in GaN based light-emitting diodes. However, the material quality of the quantum well layers need to be improved by preventing the formation of microstructures within these layers, and the importance of the role played by non-radiative centres in the QW layer needs to be elucidated, to fully realise the materials potential.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Noble-metal nanoclusters (NCs) protected by organic ligands have recently come to the forefront as potent triplet sensitizers for photon upconversion (UC) via triplet-triplet annihilation (TTA), owing to their capacity for atomic-level photophysical property customization. Among these, the rod-shaped bi-icosahedral [Au25(PPh3)10(S-C2H4Ph)5Cl2]2+ (Au-rod) NC is a particularly iconic superatomic molecular NCs, recently identified as a near-infrared (NIR)-absorbing sensitizer for TTA-UC. In this study, we synthesized Cu-doped NCs, [Au25-xCux(PPh3)10(S-C2H4Ph)5Cl2]2+ (AuCu-rod), and paired them with 9,10-bis(phenylethynyl)anthracene (BPEA) annihilator/emitter to explore the impact of Cu-doping on the triplet sensitization and NIR-UC performance. The triplet state of AuCu-rod, with lifetime of 3 µs, exhibited a modest blue shift compared to the Au-rod, resulting in the increment in the driving force for triplet energy transfer (TET) to the BPEA acceptor. The TET rate constant was determined to be 5.0 x 107 M⁻¹s⁻¹, which is an order of magnitude higher than the rate constant for the Au-rod/BPEA pair. This improvement has led to a remarkable increase in the TET efficiency. Notably, the AuCu-rod/BPEA pair facilitated the efficient UC of 805-nm NIR light into 510-nm visible light, realizing a large anti-Stokes shift close to 0.9 eV. The UC internal quantum yield of this combination was determined to be 2.33 ± 0.05 %, marking a fivefold enhancement over the Au-rod sensitizer (0.49%). Thus, alloying NC sensitizers offers a promising route to enhance UC performance by tuning the triplet state energy and optimizing the compatibility between the sensitizer and annihilator. Additionally, in this series of experiments, the formation of small amounts of BPEA microaggregates was observed. These aggregates did not undergo singlet fission and could retain multiple long-lived triplet excitons. This characteristic facilitated TTA among triplet excitons, resulting in efficient NIR-to-visible UC emission.
{"title":"Tailoring sensitization properties and improving near-infrared photon upconversion performance through alloying in superatomic molecular Au25 nanoclusters","authors":"Masaaki Mitsui, Yuki Miyoshi, Daichi Arima","doi":"10.1039/d4nr01948b","DOIUrl":"https://doi.org/10.1039/d4nr01948b","url":null,"abstract":"Noble-metal nanoclusters (NCs) protected by organic ligands have recently come to the forefront as potent triplet sensitizers for photon upconversion (UC) via triplet-triplet annihilation (TTA), owing to their capacity for atomic-level photophysical property customization. Among these, the rod-shaped bi-icosahedral [Au<small><sub>25</sub></small>(PPh<small><sub>3</sub></small>)<small><sub>10</sub></small>(S-C<small><sub>2</sub></small>H<small><sub>4</sub></small>Ph)<small><sub>5</sub></small>Cl<small><sub>2</sub></small>]<small><sup>2+</sup></small> (Au-rod) NC is a particularly iconic superatomic molecular NCs, recently identified as a near-infrared (NIR)-absorbing sensitizer for TTA-UC. In this study, we synthesized Cu-doped NCs, [Au<small><sub>25-x</sub></small>Cu<small><sub>x</sub></small>(PPh<small><sub>3</sub></small>)<small><sub>10</sub></small>(S-C<small><sub>2</sub></small>H<small><sub>4</sub></small>Ph)<small><sub>5</sub></small>Cl<small><sub>2</sub></small>]<small><sup>2+</sup></small> (AuCu-rod), and paired them with 9,10-bis(phenylethynyl)anthracene (BPEA) annihilator/emitter to explore the impact of Cu-doping on the triplet sensitization and NIR-UC performance. The triplet state of AuCu-rod, with lifetime of 3 µs, exhibited a modest blue shift compared to the Au-rod, resulting in the increment in the driving force for triplet energy transfer (TET) to the BPEA acceptor. The TET rate constant was determined to be 5.0 x 10<small><sup>7</sup></small> M<small><sup>⁻¹</sup></small>s<small><sup>⁻¹</sup></small>, which is an order of magnitude higher than the rate constant for the Au-rod/BPEA pair. This improvement has led to a remarkable increase in the TET efficiency. Notably, the AuCu-rod/BPEA pair facilitated the efficient UC of 805-nm NIR light into 510-nm visible light, realizing a large anti-Stokes shift close to 0.9 eV. The UC internal quantum yield of this combination was determined to be 2.33 ± 0.05 %, marking a fivefold enhancement over the Au-rod sensitizer (0.49%). Thus, alloying NC sensitizers offers a promising route to enhance UC performance by tuning the triplet state energy and optimizing the compatibility between the sensitizer and annihilator. Additionally, in this series of experiments, the formation of small amounts of BPEA microaggregates was observed. These aggregates did not undergo singlet fission and could retain multiple long-lived triplet excitons. This characteristic facilitated TTA among triplet excitons, resulting in efficient NIR-to-visible UC emission.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ya Na, Dangui Zhang, Yan Wang, Yi Zheng, Mo Yang, Hao Wu, Gerile Oudeng
Liquid biopsy is a non-invasive diagnostic method that can reduce the risk of complications and offers exceptional benefits in the dynamic monitoring and acquisition of heterogeneous cell population information. Optical nanomaterials with excellent light absorption, luminescence, and photoelectrochemical properties have accelerated the development of liquid biopsy technologies. Owing to the unique size effect of optical nanomaterials, their improved optical properties enable them to exhibit good sensitivity and specificity for mitigating signal interference from various molecules in body fluids. Nanomaterials with biocompatible and optical sensing properties play a crucial role in advancing the maturity and diversification of liquid biopsy technologies. This article offers a comprehensive review of recent advanced liquid biopsy technologies that utilize novel biocompatible optical nanomaterials, including fluorescence, colorimetric, photoelectrochemical, and Raman broad-spectrum-based biosensors. We focused on liquid biopsy for the most significant early biomarkers in clinical medicine, and specifically reviewed reports on the effectiveness of optical nanosensing technology in the detection of real patient samples, which may provide basic evidence for the transition of optical nanosensing technology from engineering design to clinical practice. Furthermore, we introduced the integration of optical nanosensing-based liquid biopsy with modern devices, such as smartphones, to demonstrate the potential of optical nanosensing technology in portable clinical diagnosis.
{"title":"Recent Advances of Biocompatible Optical Nanobiosensors in Liquid Biopsy: Towards Early Non-Invasive Diagnosis","authors":"Ya Na, Dangui Zhang, Yan Wang, Yi Zheng, Mo Yang, Hao Wu, Gerile Oudeng","doi":"10.1039/d4nr01719f","DOIUrl":"https://doi.org/10.1039/d4nr01719f","url":null,"abstract":"Liquid biopsy is a non-invasive diagnostic method that can reduce the risk of complications and offers exceptional benefits in the dynamic monitoring and acquisition of heterogeneous cell population information. Optical nanomaterials with excellent light absorption, luminescence, and photoelectrochemical properties have accelerated the development of liquid biopsy technologies. Owing to the unique size effect of optical nanomaterials, their improved optical properties enable them to exhibit good sensitivity and specificity for mitigating signal interference from various molecules in body fluids. Nanomaterials with biocompatible and optical sensing properties play a crucial role in advancing the maturity and diversification of liquid biopsy technologies. This article offers a comprehensive review of recent advanced liquid biopsy technologies that utilize novel biocompatible optical nanomaterials, including fluorescence, colorimetric, photoelectrochemical, and Raman broad-spectrum-based biosensors. We focused on liquid biopsy for the most significant early biomarkers in clinical medicine, and specifically reviewed reports on the effectiveness of optical nanosensing technology in the detection of real patient samples, which may provide basic evidence for the transition of optical nanosensing technology from engineering design to clinical practice. Furthermore, we introduced the integration of optical nanosensing-based liquid biopsy with modern devices, such as smartphones, to demonstrate the potential of optical nanosensing technology in portable clinical diagnosis.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Since the first realisation of the quantum anomalous Hall effect (QAHE) in a dilute magnetic doped topological insulator thin film in 2013, the quantisation temperature has been limited to less than 1 K due to magnetic disorder in dilute magnetic systems. With magnetic moments ordered into the crystal lattice, the intrinsic magnetic topological insulator MnBi2Te4 has the potential to eliminate or significantly reduce magnetic disorder, and improve the quantisation temperature. Surprisingly, to date, the QAHE has yet to be observed in molecular beam epitaxy (MBE)-grown MnBi2Te4 thin films at zero magnetic field, and what leads to the difficulty in quantisation remains a mystery. Although bulk MnBi2Te4 and exfoliated flakes have been well studied, revealing both the QAH effect and axion insulator phases, experimental progress on MBE thin films has been slower. Understanding how the breakdown of QAHE occurs in MnBi2Te4 thin films and finding solutions that will enable mass-producing millimetre-size QAHE devices operating at elevated temperatures is required. In this mini-review, we will summarise recent studies on the electronic and magnetic properties of MBE MnBi2Te4 thin films and discuss mechanisms that could explain the failure of QAHE from the aspects of defects, electronic structure, magnetic order, and consequences of their delicate interplay. Finally, we propose several strategies for realising QAHE at elevated temperatures in MnBi2Te4 thin films.
{"title":"Recent progress on MnBi2Te4 epitaxial thin films as a platform for realising quantum anomalous Hall effect","authors":"Qile Li, Sung-Kwan Mo, Mark T. Edmonds","doi":"10.1039/d4nr00194j","DOIUrl":"https://doi.org/10.1039/d4nr00194j","url":null,"abstract":"Since the first realisation of the quantum anomalous Hall effect (QAHE) in a dilute magnetic doped topological insulator thin film in 2013, the quantisation temperature has been limited to less than 1 K due to magnetic disorder in dilute magnetic systems. With magnetic moments ordered into the crystal lattice, the intrinsic magnetic topological insulator MnBi<small><sub>2</sub></small>Te<small><sub>4</sub></small> has the potential to eliminate or significantly reduce magnetic disorder, and improve the quantisation temperature. Surprisingly, to date, the QAHE has yet to be observed in molecular beam epitaxy (MBE)-grown MnBi<small><sub>2</sub></small>Te<small><sub>4</sub></small> thin films at zero magnetic field, and what leads to the difficulty in quantisation remains a mystery. Although bulk MnBi<small><sub>2</sub></small>Te<small><sub>4</sub></small> and exfoliated flakes have been well studied, revealing both the QAH effect and axion insulator phases, experimental progress on MBE thin films has been slower. Understanding how the breakdown of QAHE occurs in MnBi<small><sub>2</sub></small>Te<small><sub>4</sub></small> thin films and finding solutions that will enable mass-producing millimetre-size QAHE devices operating at elevated temperatures is required. In this mini-review, we will summarise recent studies on the electronic and magnetic properties of MBE MnBi<small><sub>2</sub></small>Te<small><sub>4</sub></small> thin films and discuss mechanisms that could explain the failure of QAHE from the aspects of defects, electronic structure, magnetic order, and consequences of their delicate interplay. Finally, we propose several strategies for realising QAHE at elevated temperatures in MnBi<small><sub>2</sub></small>Te<small><sub>4</sub></small> thin films.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaolei Wang, Hongxi Yu, Dan Liu, Boxian Hu, Ruihang Zhang, Lihua Hu, Guiping Hu, Cheng Li
Mechanical properties, as a crucial physical property, have a significant impact on the occurrence, development, and metastasis of tumors. Regulating the mechanical properties of tumors to enhance their sensitivity to radiotherapy and chemotherapy has become an important strategy in the field of cancer treatment. Over the past few decades, nanomaterials have made remarkable progress in cancer therapy, either based on their intrinsic properties or as drug delivery carriers. However, the investigation of nanomaterials of mechanical regulation in tumor therapy is currently in its initial stages. The mechanical properties of nanomaterials themselves, drug carrier targeting, and regulation of the mechanical environment of tumor tissue have far-reaching effects on the efficient uptake of drugs and clinical tumor treatment. Therefore, this review aims to comprehensively summarize the applications and research progresses of nanomaterials in tumor therapy based on the regulation of mechanical properties, in order to provide strong support for further research and the development of treatment strategies in this field.
{"title":"The Application of Nanomaterials in Tumor Therapy Based on the Regulation of Mechanical Properties","authors":"Xiaolei Wang, Hongxi Yu, Dan Liu, Boxian Hu, Ruihang Zhang, Lihua Hu, Guiping Hu, Cheng Li","doi":"10.1039/d4nr01812e","DOIUrl":"https://doi.org/10.1039/d4nr01812e","url":null,"abstract":"Mechanical properties, as a crucial physical property, have a significant impact on the occurrence, development, and metastasis of tumors. Regulating the mechanical properties of tumors to enhance their sensitivity to radiotherapy and chemotherapy has become an important strategy in the field of cancer treatment. Over the past few decades, nanomaterials have made remarkable progress in cancer therapy, either based on their intrinsic properties or as drug delivery carriers. However, the investigation of nanomaterials of mechanical regulation in tumor therapy is currently in its initial stages. The mechanical properties of nanomaterials themselves, drug carrier targeting, and regulation of the mechanical environment of tumor tissue have far-reaching effects on the efficient uptake of drugs and clinical tumor treatment. Therefore, this review aims to comprehensively summarize the applications and research progresses of nanomaterials in tumor therapy based on the regulation of mechanical properties, in order to provide strong support for further research and the development of treatment strategies in this field.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dirac fermions, particles with zero rest mass, are observed in topological materials and are believed to play key role in the exoticities in fundamental science and advancement of quantum technology. Most of the topological systems studied so far are weakly correlated systems and their properties in the presence of electron correlation is an interesting emerging area of research, where the electron correlation is expected to enhance the effective mass of the particles. Here, we studied the properties of Dirac bands in a nonsymmorphic layered Kondo lattice system, CeAgSb$_2$ employing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations. In addition to the Dirac cones due to non-symmorphic symmetry, this material hosts Dirac fermions in the squarenet layer in proximity of a strongly correlated Ce-layer exhibiting Kondo behavior. Experimental results reveal crossings of the highly dispersive linear bands at the Brillouin zone boundary due to non-symmorphic symmetry. In addition, there are anisotropic Dirac cones constituted by the squarenet Sb 5$p$ states forming a diamond-shaped nodal line. These Dirac bands are linear in a wide energy range with a unusually high slope. Interestingly, near the local Ce 4$f$ bands, these bands exhibit a change in slope akin to formation of a 'kink' observed in other materials due to electron-phonon coupling. Emergence of such exotic properties in proximity to strongly correlated electronic states has significant implication in the study of complex quantum materials including unconventional superconductors.
狄拉克费米子是一种静止质量为零的粒子，在拓扑材料中可以观察到它的存在，并被认为在基础科学的奇异性和量子技术的进步中发挥着关键作用。迄今研究的大多数拓扑系统都是弱相关系统，而它们在电子相关情况下的性质是一个有趣的新兴研究领域，电子相关有望增强粒子的有效质量。在此，我们利用高分辨率角度分辨光发射光谱和第一原理计算，研究了非非晶层状近藤晶格体系 CeAgSb$_2$ 中的狄拉克带性质。除了由于非对称性而产生的狄拉克锥之外，这种材料在邻近表现出 Kondo 行为的强相关 Ce 层的方网层中还存在狄拉克费米子。实验结果表明，由于非对称性，在布里渊区边界存在高色散线性带交叉。此外，还存在各向异性的狄拉克锥，由形成菱形结线的正方形 Sb 5$p$ 态构成。这些狄拉克带在很宽的能量范围内呈线性，斜率异常高。有趣的是，在局部 Ce 4$f$ 带附近，这些带的斜率发生了变化，类似于在其他材料中观察到的由于电子-声子耦合而形成的 "扭结"。在强相关电子态附近出现这种奇异特性，对研究包括非常规超导体在内的复杂量子材料具有重要意义。
{"title":"Anomalies in the Dirac bands in proximity of correlated electrons","authors":"Sawani Datta, Khadiza Ali, Rahul Verma, Bahadur Singh, Saroj Dash, A. Thamizhavel, Kalobaran Maiti","doi":"10.1039/d4nr01535e","DOIUrl":"https://doi.org/10.1039/d4nr01535e","url":null,"abstract":"Dirac fermions, particles with zero rest mass, are observed in topological materials and are believed to play key role in the exoticities in fundamental science and advancement of quantum technology. Most of the topological systems studied so far are weakly correlated systems and their properties in the presence of electron correlation is an interesting emerging area of research, where the electron correlation is expected to enhance the effective mass of the particles. Here, we studied the properties of Dirac bands in a nonsymmorphic layered Kondo lattice system, CeAgSb$_2$ employing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations. In addition to the Dirac cones due to non-symmorphic symmetry, this material hosts Dirac fermions in the squarenet layer in proximity of a strongly correlated Ce-layer exhibiting Kondo behavior. Experimental results reveal crossings of the highly dispersive linear bands at the Brillouin zone boundary due to non-symmorphic symmetry. In addition, there are anisotropic Dirac cones constituted by the squarenet Sb 5$p$ states forming a diamond-shaped nodal line. These Dirac bands are linear in a wide energy range with a unusually high slope. Interestingly, near the local Ce 4$f$ bands, these bands exhibit a change in slope akin to formation of a 'kink' observed in other materials due to electron-phonon coupling. Emergence of such exotic properties in proximity to strongly correlated electronic states has significant implication in the study of complex quantum materials including unconventional superconductors.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rodrigo A Valenzuela-Fernández, Arianne Maine, Julien Cardin, Xavier Portier, Christophe Labbé, Cristóbal Pinto, Francisco Melo, Nancy Pizarro, Víctor Vargas, Camilo Segura, Antonio Galdámez
Correction for 'Photoluminescence modification of europium(III)-doped MAl2O4 (M = Zn, Mg) spinels induced by Ag@SiO2 core-shell nanoparticles' by Rodrigo A. Valenzuela-Fernández et al., Nanoscale, 2024, https://doi.org/10.1039/d4nr01526f.
Jihui Li, Shaodong Sun, Jieli Lyu, Xiaojing Yu, Jiaqing Zhao, Man Yang, Bian Yang, Qing Yang, Jie Cui
Near-infrared (NIR) light-induced photothermal effect is beneficial for accelerating the catalytic process, so that it is imperative to develop novel photothermal catalysts for promoting the practical application. Herein, we have purposefully synthesized NIR-responsive Cu2O/WO2 Ohmic contact photothermal catalysts through a facile ethylene glycol-assisted liquid-phase reduction method. As for this photothermal catalyst, new-typed NIR-responsive Cu2O semiconductor is integrated with NIR-responsive WO2 semimetal component to form an Ohmic contact, which is more beneficial for simultaneously promoting photocharge separation and enhancing NIR light absorption for high-efficient photothermal effect. As expected, the Cu2O/WO2 composite displays higher NIR light-driven photothermal catalytic performance for removing tetracycline wastewater. Various characterizations and density functional theory calculations have been performed to uncover the mechanism insight into the NIR light-driven Cu2O/WO2 Ohmic contact photothermal catalysts in depth. Wistfully, this research could provide a useful guideline for scientific people now focusing on photothermal engineering of new composite photocatalysts.
{"title":"Mechanism insight into near-infrared light-driven Cu2O/WO2 Ohmic contact photothermal catalysts for high-efficient antibiotic wastewater purification","authors":"Jihui Li, Shaodong Sun, Jieli Lyu, Xiaojing Yu, Jiaqing Zhao, Man Yang, Bian Yang, Qing Yang, Jie Cui","doi":"10.1039/d4nr01472c","DOIUrl":"https://doi.org/10.1039/d4nr01472c","url":null,"abstract":"Near-infrared (NIR) light-induced photothermal effect is beneficial for accelerating the catalytic process, so that it is imperative to develop novel photothermal catalysts for promoting the practical application. Herein, we have purposefully synthesized NIR-responsive Cu2O/WO2 Ohmic contact photothermal catalysts through a facile ethylene glycol-assisted liquid-phase reduction method. As for this photothermal catalyst, new-typed NIR-responsive Cu2O semiconductor is integrated with NIR-responsive WO2 semimetal component to form an Ohmic contact, which is more beneficial for simultaneously promoting photocharge separation and enhancing NIR light absorption for high-efficient photothermal effect. As expected, the Cu2O/WO2 composite displays higher NIR light-driven photothermal catalytic performance for removing tetracycline wastewater. Various characterizations and density functional theory calculations have been performed to uncover the mechanism insight into the NIR light-driven Cu2O/WO2 Ohmic contact photothermal catalysts in depth. Wistfully, this research could provide a useful guideline for scientific people now focusing on photothermal engineering of new composite photocatalysts.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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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