Jannik Mehmel, Carlos M. Jimenez-Muñoz, Filip Rivic, Vera Krewald, Rolf Schäfer
The magnetic behavior of endohedrally transition-metal-doped tetrel clusters Sn12TM (TM = Cr, Mn, Fe) was investigated using a combined experimental and theoretical approach. Based on an improved experimental setup, the magnetic deflection was measured over a wide temperature range of Tnozzle = 16–240 K. From a Curie analysis of the experimentally observed single-sided shift at high nozzle temperatures, the spin multiplicities and g-factors were determined. It was observed that all three nanoclusters analyzed are paramagnetic, with Sn12Mn being a sextet with g = 2.1 ± 0.1, while Sn12Cr is a quintet with the same g-factor and Sn12Fe is also a quintet but with a higher g-factor of 2.4 ± 0.1. In order to better understand the interplay between geometric and electronic structures and their influence on magnetism, a global geometry optimization was carried out, followed by a quantum-chemical analysis of the electronic structure using density functional theory (DFT) and wavefunction methods. The multi-reference calculations proved particularly important for Sn12Fe because DFT fails to correctly predict the value of the g-factor. To describe the electronic ground state of Sn12Fe, two reference configurations must be taken into account. A charge transfer from the Sn ligands to Fe manifests in very low-lying electronic excitations. These charge transfer excitations lead to a significant increase in the g-factor compared to the value of the free electron due to the large spin–orbit coupling constant of Sn. As a result, in contrast to Sn12Mn and Sn12Cr, the spin density of Sn12Fe is strongly delocalized over the entire cluster framework.
{"title":"Magnetism of transition-metal-doped tetrel nanoclusters: multi-reference character and spin–orbit effects in Sn12TM (TM = Cr, Mn, Fe)","authors":"Jannik Mehmel, Carlos M. Jimenez-Muñoz, Filip Rivic, Vera Krewald, Rolf Schäfer","doi":"10.1039/d4nr03920c","DOIUrl":"https://doi.org/10.1039/d4nr03920c","url":null,"abstract":"The magnetic behavior of endohedrally transition-metal-doped tetrel clusters Sn<small><sub>12</sub></small>TM (TM = Cr, Mn, Fe) was investigated using a combined experimental and theoretical approach. Based on an improved experimental setup, the magnetic deflection was measured over a wide temperature range of <em>T</em><small><sub>nozzle</sub></small> = 16–240 K. From a Curie analysis of the experimentally observed single-sided shift at high nozzle temperatures, the spin multiplicities and <em>g</em>-factors were determined. It was observed that all three nanoclusters analyzed are paramagnetic, with Sn<small><sub>12</sub></small>Mn being a sextet with <em>g</em> = 2.1 ± 0.1, while Sn<small><sub>12</sub></small>Cr is a quintet with the same <em>g</em>-factor and Sn<small><sub>12</sub></small>Fe is also a quintet but with a higher <em>g</em>-factor of 2.4 ± 0.1. In order to better understand the interplay between geometric and electronic structures and their influence on magnetism, a global geometry optimization was carried out, followed by a quantum-chemical analysis of the electronic structure using density functional theory (DFT) and wavefunction methods. The multi-reference calculations proved particularly important for Sn<small><sub>12</sub></small>Fe because DFT fails to correctly predict the value of the <em>g</em>-factor. To describe the electronic ground state of Sn<small><sub>12</sub></small>Fe, two reference configurations must be taken into account. A charge transfer from the Sn ligands to Fe manifests in very low-lying electronic excitations. These charge transfer excitations lead to a significant increase in the <em>g</em>-factor compared to the value of the free electron due to the large spin–orbit coupling constant of Sn. As a result, in contrast to Sn<small><sub>12</sub></small>Mn and Sn<small><sub>12</sub></small>Cr, the spin density of Sn<small><sub>12</sub></small>Fe is strongly delocalized over the entire cluster framework.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"48 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936399","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}
Dylan Shearsby, Jiaqi Joshua Wu, Dekun Yang, Bo Peng
Benefiting from improved stability due to stronger interlayer van der Waals interactions, few-layer fullerene networks are experimentally more accessible compared to monolayer polymeric C60. However, there is a lack of systematic theoretical studies on the material properties of few-layer C60 networks. Here, we compare the structural, electronic and optical properties of bilayer and monolayer fullerene networks. The band gap and band-edge positions remain mostly unchanged after stacking two layers into a bilayer, enabling the bilayer to be almost as efficient a photocatalyst as the monolayer. The effective mass ratio along different directions is varied for conduction band states due to interlayer interactions, leading to enhanced anisotropy in carrier transport. Additionally, stronger exciton absorption is found in the bilayer than that in the monolayer over the entire visible light range, rendering the bilayer a more promising candidate for photovoltaics. Moreoever, the polarisation dependence of optical absorption in the bilayer is increased in the red-yellow light range, offering unique opportunities in photonics and display technologies with tailored optical properties over specific directions. Our study provides strategies to tune electronic and optical properties of 2D polymeric C60 via the introduction of stacking degrees of freedom.
{"title":"Tuning electronic and optical properties of 2D polymeric C60 by stacking two layers","authors":"Dylan Shearsby, Jiaqi Joshua Wu, Dekun Yang, Bo Peng","doi":"10.1039/d4nr04540h","DOIUrl":"https://doi.org/10.1039/d4nr04540h","url":null,"abstract":"Benefiting from improved stability due to stronger interlayer van der Waals interactions, few-layer fullerene networks are experimentally more accessible compared to monolayer polymeric C<small><sub>60</sub></small>. However, there is a lack of systematic theoretical studies on the material properties of few-layer C<small><sub>60</sub></small> networks. Here, we compare the structural, electronic and optical properties of bilayer and monolayer fullerene networks. The band gap and band-edge positions remain mostly unchanged after stacking two layers into a bilayer, enabling the bilayer to be almost as efficient a photocatalyst as the monolayer. The effective mass ratio along different directions is varied for conduction band states due to interlayer interactions, leading to enhanced anisotropy in carrier transport. Additionally, stronger exciton absorption is found in the bilayer than that in the monolayer over the entire visible light range, rendering the bilayer a more promising candidate for photovoltaics. Moreoever, the polarisation dependence of optical absorption in the bilayer is increased in the red-yellow light range, offering unique opportunities in photonics and display technologies with tailored optical properties over specific directions. Our study provides strategies to tune electronic and optical properties of 2D polymeric C<small><sub>60</sub></small> via the introduction of stacking degrees of freedom.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"59 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936398","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}
Hybrid polyionic complexes (HPICs) are colloidal structures with a charged core rich in metal ions and a neutral hydrophilic corona. Their properties, whether as reservoirs or catalysts, depend on the accessibility and environment of the metal ions. This study demonstrates that modifying the coordination sphere of these ions can tune the properties of HPICs by altering the composition of the complexing block or varying formulation conditions. Hence, double hydrophilic block copolymers were synthesized using RAFT polymerization, with polyethylene glycol as the neutral block and different ratios of acrylic acid (AA) and vinylphosphonic acid (VPA) as the functiional block and further complexed with Fe(III) ions. The resulting iron-based HPICs with higher VPA content were more stable at low pH due to stronger VPA-iron interactions, but their catalytic efficiency in the photo-Fenton process decreased at higher pH. In nanoparticle synthesis, polymers with higher VPA content produced smaller, less-defined Prussian blue nanoparticles, while a 50/50 AA/VPA ratio resulted in uniform nanoparticles and optimal reactivity. Multivariate analysis revealed that not only composition but also local structural organization impacts HPIC properties, influenced by changes in the complexing block structure (e.g., statistical, block) or formulation conditions.
{"title":"How tailor-made copolymers can control the structure and properties of hybrid nanomaterials: the case of polyionic complexes","authors":"Liming Peng, Maksym Odnoroh, Mathias Destarac, Yannick Coppel, Céline Delmas, Florence Benoit-Marquie, Christophe Mingotaud, Jean-Daniel Marty","doi":"10.1039/d4nr04332d","DOIUrl":"https://doi.org/10.1039/d4nr04332d","url":null,"abstract":"Hybrid polyionic complexes (HPICs) are colloidal structures with a charged core rich in metal ions and a neutral hydrophilic corona. Their properties, whether as reservoirs or catalysts, depend on the accessibility and environment of the metal ions. This study demonstrates that modifying the coordination sphere of these ions can tune the properties of HPICs by altering the composition of the complexing block or varying formulation conditions. Hence, double hydrophilic block copolymers were synthesized using RAFT polymerization, with polyethylene glycol as the neutral block and different ratios of acrylic acid (AA) and vinylphosphonic acid (VPA) as the functiional block and further complexed with Fe(III) ions. The resulting iron-based HPICs with higher VPA content were more stable at low pH due to stronger VPA-iron interactions, but their catalytic efficiency in the photo-Fenton process decreased at higher pH. In nanoparticle synthesis, polymers with higher VPA content produced smaller, less-defined Prussian blue nanoparticles, while a 50/50 AA/VPA ratio resulted in uniform nanoparticles and optimal reactivity. Multivariate analysis revealed that not only composition but also local structural organization impacts HPIC properties, influenced by changes in the complexing block structure (e.g., statistical, block) or formulation conditions.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"28 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936404","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}
Duhaul Biqal Kautsar, Phong Hoai Le, Ai Ando, Eishi Tanabe, Kiet Le Anh Cao, Eka Lutfi Septiani, Tomoyuki Hirano, Takashi Ogi
Highly ordered porous structured particles comprising three-way catalyst (TWC) nanoparticles have attracted attention because of their remarkable catalytic performance. However, the conditions for controlling their pore arrangement to form interconnected pore structures remain unclear. In particular, the correlation between framework thickness (distance between pores) or macroporosity and the diffusion of gaseous reactants to achieve a high catalytic performance has not been extensively discussed. Here, the interconnected pore structure was successfully controlled by adjusting the precursor components (i.e., template particle concentration) via a template-assisted spray process. A cross-sectional image analysis was conducted to comprehensively examine the internal structure and porous properties (framework thickness and macroporosity) of the porous TWC particles. In addition, we propose mathematical equations to predict the framework thickness and macroporosity, as well as determine the critical conditions that caused the formation of interconnected pores and broken structures in the porous TWC particles. The evaluation of CO oxidation performance revealed that porous TWC particles with an interconnected pore structure, thin framework, and high macroporosity exhibited a high catalytic performance owing to the effective diffusion and utilization of their internal parts. The study findings provide valuable insights into the design of porous TWC particles with interconnected pore structures to enhance exhaust gas emission control in real-world applications.
{"title":"Enhancing CO oxidation performance by controlling the interconnected pore structure in porous three-way catalyst particles","authors":"Duhaul Biqal Kautsar, Phong Hoai Le, Ai Ando, Eishi Tanabe, Kiet Le Anh Cao, Eka Lutfi Septiani, Tomoyuki Hirano, Takashi Ogi","doi":"10.1039/d4nr03770g","DOIUrl":"https://doi.org/10.1039/d4nr03770g","url":null,"abstract":"Highly ordered porous structured particles comprising three-way catalyst (TWC) nanoparticles have attracted attention because of their remarkable catalytic performance. However, the conditions for controlling their pore arrangement to form interconnected pore structures remain unclear. In particular, the correlation between framework thickness (distance between pores) or macroporosity and the diffusion of gaseous reactants to achieve a high catalytic performance has not been extensively discussed. Here, the interconnected pore structure was successfully controlled by adjusting the precursor components (i.e., template particle concentration) via a template-assisted spray process. A cross-sectional image analysis was conducted to comprehensively examine the internal structure and porous properties (framework thickness and macroporosity) of the porous TWC particles. In addition, we propose mathematical equations to predict the framework thickness and macroporosity, as well as determine the critical conditions that caused the formation of interconnected pores and broken structures in the porous TWC particles. The evaluation of CO oxidation performance revealed that porous TWC particles with an interconnected pore structure, thin framework, and high macroporosity exhibited a high catalytic performance owing to the effective diffusion and utilization of their internal parts. The study findings provide valuable insights into the design of porous TWC particles with interconnected pore structures to enhance exhaust gas emission control in real-world applications.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"20 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142937037","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}
Yu Xin, Bin Sun, Yifei Kong, Bojie Zhao, Jiayang Chen, Kui Shen, Yamin Zhang
Bioelectronic devices with medical functions have attracted widespread attention in recent years. Power supplies are crucial components in these devices, which ensures their stable operation. Biomedical devices that utilize external power supplies and extended electrical wires limit patient mobility and increase the risk of discomfort and infection. To address these issues, self-powered devices with integrated power supplies have emerged, including triboelectric nanogenerators, piezoelectric nanogenerators, thermoelectric generators, batteries, biofuel cells, and solar cells. This minireview highlights the recent advances in the power supplies utilized in these self-powered devices. A concluding section discusses the subsisting challenges and future perspectives in integrated power supply technologies and design and manufacturing of self-powered devices.
{"title":"Advances in Integrated Power Supplies for Self-Powered Bioelectronic Devices","authors":"Yu Xin, Bin Sun, Yifei Kong, Bojie Zhao, Jiayang Chen, Kui Shen, Yamin Zhang","doi":"10.1039/d4nr04645e","DOIUrl":"https://doi.org/10.1039/d4nr04645e","url":null,"abstract":"Bioelectronic devices with medical functions have attracted widespread attention in recent years. Power supplies are crucial components in these devices, which ensures their stable operation. Biomedical devices that utilize external power supplies and extended electrical wires limit patient mobility and increase the risk of discomfort and infection. To address these issues, self-powered devices with integrated power supplies have emerged, including triboelectric nanogenerators, piezoelectric nanogenerators, thermoelectric generators, batteries, biofuel cells, and solar cells. This minireview highlights the recent advances in the power supplies utilized in these self-powered devices. A concluding section discusses the subsisting challenges and future perspectives in integrated power supply technologies and design and manufacturing of self-powered devices.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"36 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936401","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}
Ekaterina I. Marchenko, Vadim V. Korolev, Elena A. Kobeleva, Nikolai A. Belich, Natalia Udalova, Nikolay N. Eremin, Eugene A. Goodilin, Alexey B. Tarasov
Identification of crystal structures is a crucial stage in the exploration of novel functional materials. This procedure is usually time-consuming and can be false-positive or false-negative. This necessitates a significant level of expert proficiency in the field of crystallography and, especially, requires deep experience in perovskite - related structures of hybrid perovskites. Our work is devoted to the machine learning classification of structure types of hybrid lead halides based on available X-ray diffraction data. Here, we proposed a simple approach to quickly identify of dimensionality of inorganic substructures, types of lead halide polyhedra connectivity and structure types using common powder XRD data and ML - decision tree classification model. The average accuracy of our ML algorithm in predicting the dimensionality of inorganic substructure, type of connection of lead halide and inorganic substructure topology by theoretically calculated XRD pattern among 14 most common structure types reaches 0.86±0.05, 0.827±0.028 and 0.71±0.05, respectively. The validation of our decision tree classification ML model on experimental XRD data shows the accuracies of 1.0 and 0.82 for the dimension and structure type prediction. Thus, our approach can significantly simplify and accelerate the interpretation of highly complicated XRD data for hybrid lead halides.
{"title":"Machine learning recognition of hybrid lead halide perovskites and perovskite-related structures out of X-ray diffraction patterns","authors":"Ekaterina I. Marchenko, Vadim V. Korolev, Elena A. Kobeleva, Nikolai A. Belich, Natalia Udalova, Nikolay N. Eremin, Eugene A. Goodilin, Alexey B. Tarasov","doi":"10.1039/d4nr04531a","DOIUrl":"https://doi.org/10.1039/d4nr04531a","url":null,"abstract":"Identification of crystal structures is a crucial stage in the exploration of novel functional materials. This procedure is usually time-consuming and can be false-positive or false-negative. This necessitates a significant level of expert proficiency in the field of crystallography and, especially, requires deep experience in perovskite - related structures of hybrid perovskites. Our work is devoted to the machine learning classification of structure types of hybrid lead halides based on available X-ray diffraction data. Here, we proposed a simple approach to quickly identify of dimensionality of inorganic substructures, types of lead halide polyhedra connectivity and structure types using common powder XRD data and ML - decision tree classification model. The average accuracy of our ML algorithm in predicting the dimensionality of inorganic substructure, type of connection of lead halide and inorganic substructure topology by theoretically calculated XRD pattern among 14 most common structure types reaches 0.86±0.05, 0.827±0.028 and 0.71±0.05, respectively. The validation of our decision tree classification ML model on experimental XRD data shows the accuracies of 1.0 and 0.82 for the dimension and structure type prediction. Thus, our approach can significantly simplify and accelerate the interpretation of highly complicated XRD data for hybrid lead halides.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"100 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936403","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}
Electrochemical nitrogen reduction reaction (NRR) has been regarded as a green and promising alternative to the traditional Haber–Bosch process. However, the high bond energy (940.95 kJ mol-1) of the N≡N triple bond hinders the adsorption and activation of N₂ molecules, which is a critical factor restricting the catalytic performance of catalysts and its large-scale applications. Herein, Mn/C60 heterostructure is constructed via a simple grinding and calcination process and achieve an extraordinary Faradaic efficiency of 42.18% and a NH3 yield rate of 14.52 μg h−1 mgcat−1 at −0.4 V vs. RHE in 0.08 M Na2HPO4. Our experimental and theoretical results solidly confirm that the spontaneous charge transfer at the Mn/C60 heterointerface promote the formation of built-in electric field, which facilitate the electron transfer from Mn towards C60 and fabricate localized electrophilic and nucleophilic regions. The formation of the space-charge region effectively optimized the adsorption energy of forming key intermediate *NH-*NH2 and also reduced the free energy barrier for the hydrogenation step of *NH-*NH to *NH-*NH2. Furthermore, the calculated lower limiting potential (UL(NRR)) in Mn/C60 relative to HER (UL(HER)) demonstrating the enhanced selectivity toward NRR. This work provided new insights into enhancing the activity and performance of electrocatalysts for NRR by constructing heterojunctions to improve nitrogen adsorption.
{"title":"Elaborated Built-In Electric Field in Mn/C60 Heterojunction Promotes Electrocatalytic Nitrogen Reduction to Ammonia","authors":"Hao Xue, Kaiheng Zhao, Denglei Gao, Fangying Duan, Zijian Gao, Wenjia Yu, Sha Li, Menglei Yuan, Zongjing Lu","doi":"10.1039/d4nr04496g","DOIUrl":"https://doi.org/10.1039/d4nr04496g","url":null,"abstract":"Electrochemical nitrogen reduction reaction (NRR) has been regarded as a green and promising alternative to the traditional Haber–Bosch process. However, the high bond energy (940.95 kJ mol-1) of the N≡N triple bond hinders the adsorption and activation of N₂ molecules, which is a critical factor restricting the catalytic performance of catalysts and its large-scale applications. Herein, Mn/C60 heterostructure is constructed via a simple grinding and calcination process and achieve an extraordinary Faradaic efficiency of 42.18% and a NH3 yield rate of 14.52 μg h−1 mgcat−1 at −0.4 V vs. RHE in 0.08 M Na2HPO4. Our experimental and theoretical results solidly confirm that the spontaneous charge transfer at the Mn/C60 heterointerface promote the formation of built-in electric field, which facilitate the electron transfer from Mn towards C60 and fabricate localized electrophilic and nucleophilic regions. The formation of the space-charge region effectively optimized the adsorption energy of forming key intermediate *NH-*NH2 and also reduced the free energy barrier for the hydrogenation step of *NH-*NH to *NH-*NH2. Furthermore, the calculated lower limiting potential (UL(NRR)) in Mn/C60 relative to HER (UL(HER)) demonstrating the enhanced selectivity toward NRR. This work provided new insights into enhancing the activity and performance of electrocatalysts for NRR by constructing heterojunctions to improve nitrogen adsorption.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"31 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936405","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}
Homogeneous mixtures undergo phase separation to generate rich heterogeneous structures and enable complex physiological activity and delicate design of artificial materials. Beyond in free space, the strong coupling between migrating components and spatial confinement determines the essential spatial compartment of phase separation and waits to be continuously explored. Here, we report a selective phase separation (SPS) behavior of polymers under the mobile two-dimensional (2D) confinement by graphene oxide (GO) sheets. The selection of poor solvent triggers the occurrence of SPS in homogeneous solution of GO and polymers. We reveal that the self-limiting spatial confinement of GO sheets prefers the migration of polymers to form independent and continuous phase in 2D gallery. We conclude the quantitative rule of size and continuity of polymeric phases in correlation with solvent properties and solute constitutes. The found SPS allows the facile generation of heterogenous nanostructures in GO/polymer composites. We initiate a SPS wet-spinning to fabricate radial heterogenous fibrous graphene composite fibers with ultrahigh breakage elongation and superior flexibility. The found SPS can inspire more exotic phase separation behaviors under mobile 2D confinement and offers a facile method to delicate design heterogeneous nanostructure of 2D materials.
{"title":"Self-limiting Selective Phase Separation of Graphene Oxide and Polymer Composites Solution","authors":"Feifan Chen, Lidan Wang, Kaiwen Li, Rui Guo, Yicong Qin, Chenwei Shen, Yingjun Liu, Zhen Xu, Chao Gao","doi":"10.1039/d4nr04636f","DOIUrl":"https://doi.org/10.1039/d4nr04636f","url":null,"abstract":"Homogeneous mixtures undergo phase separation to generate rich heterogeneous structures and enable complex physiological activity and delicate design of artificial materials. Beyond in free space, the strong coupling between migrating components and spatial confinement determines the essential spatial compartment of phase separation and waits to be continuously explored. Here, we report a selective phase separation (SPS) behavior of polymers under the mobile two-dimensional (2D) confinement by graphene oxide (GO) sheets. The selection of poor solvent triggers the occurrence of SPS in homogeneous solution of GO and polymers. We reveal that the self-limiting spatial confinement of GO sheets prefers the migration of polymers to form independent and continuous phase in 2D gallery. We conclude the quantitative rule of size and continuity of polymeric phases in correlation with solvent properties and solute constitutes. The found SPS allows the facile generation of heterogenous nanostructures in GO/polymer composites. We initiate a SPS wet-spinning to fabricate radial heterogenous fibrous graphene composite fibers with ultrahigh breakage elongation and superior flexibility. The found SPS can inspire more exotic phase separation behaviors under mobile 2D confinement and offers a facile method to delicate design heterogeneous nanostructure of 2D materials.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"98 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142935367","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}
Divesh Nazar, Amelia Dawn Waters, Maxwell Marshal Kannen, Dulanjan Harankahage, Jiamin Huang, Mikhail Zamkov
Laser diodes based on solution-processed semiconductor quantum dots (QDs) present an economical and color-tunable alternative to traditional epitaxial lasers. However, their efficiency is significantly limited by non-radiative Auger recombination, a process that increases lasing thresholds and diminishes device longevity through excessive heat generation. Recent advancements indicate that these limitations can be mitigated by employing spherical quantum wells, or quantum shells (QSs), in place of conventional QDs. The unique QS geometry is designed to suppress multi-exciton Auger decay through exciton–exciton repulsion, thereby extending multi-exciton lifetimes and enhancing their radiative recombination efficiency. In this review, we examine optoelectronic characteristics of QSs and discuss their integration into photonic laser cavities. We further present experimental data demonstrating QS performance in femtosecond, quasi-continuous-wave (quasi-CW), and two-photon upconverted laser configurations, underscoring QS capability to achieve efficient lasing with reduced thresholds and lower energy losses.
{"title":"Colloidal semiconductor quantum shells for solution-processed laser applications","authors":"Divesh Nazar, Amelia Dawn Waters, Maxwell Marshal Kannen, Dulanjan Harankahage, Jiamin Huang, Mikhail Zamkov","doi":"10.1039/d4nr04653f","DOIUrl":"https://doi.org/10.1039/d4nr04653f","url":null,"abstract":"Laser diodes based on solution-processed semiconductor quantum dots (QDs) present an economical and color-tunable alternative to traditional epitaxial lasers. However, their efficiency is significantly limited by non-radiative Auger recombination, a process that increases lasing thresholds and diminishes device longevity through excessive heat generation. Recent advancements indicate that these limitations can be mitigated by employing spherical quantum wells, or quantum shells (QSs), in place of conventional QDs. The unique QS geometry is designed to suppress multi-exciton Auger decay through exciton–exciton repulsion, thereby extending multi-exciton lifetimes and enhancing their radiative recombination efficiency. In this review, we examine optoelectronic characteristics of QSs and discuss their integration into photonic laser cavities. We further present experimental data demonstrating QS performance in femtosecond, quasi-continuous-wave (quasi-CW), and two-photon upconverted laser configurations, underscoring QS capability to achieve efficient lasing with reduced thresholds and lower energy losses.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"22 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142935368","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}
Electrocatalytic carbon dioxide reduction reaction (CO2RR) is an attractive method for converting atmospheric CO2 into value-added chemicals and fuels. In order to overcome the low efficiency and durability that hinder its practical application, a significant amount of research has been dedicated to designing novel catalysts at the nanoscale and even the atomic scale. Two-dimensional (2D) monolayer materials inherit the merits of both 2D materials and single-atom materials. Through bridging the gap between heterogeneous and homogeneous catalysis, 2D monolayer materials exhibit great potential in CO2RR due to the unique structural/electronic properties, high atom utilization , low mass transfer resistance and uniform active sites. Here, we systematically overview the development and application of 2D monolayer catalysts for electrocatalytic CO2RR. Firstly, an overview of the CO2RR technology is presented. Subsequently, a comprehensive discussion is undertaken on various types of 2D monolayer electrocatalysts, such as 2D graphene-based materials, 2D monolayer metal-organic frameworks (MOFs), 2D monolayer covalent organic frameworks (COFs) and 2D monolayer metal-based materials. Their respective electrocatalytic performances are also systematically analyzed. More importantly, novel perspectives on the primary challenges and opportunities associated with the utilization of 2D monolayer materials in CO2RR are presented. Achieving high-quality 2D monolayer materials and producing high-selective multi-carbon products remains the two major challenges in the design, synthesis and appliaction of 2D monolayer electrocatalysts. Addressing these synthesis-related and performance-related issues is sigificant for the progression and practical utilization of 2D monolayer materials in CO₂RR.
{"title":"2D Monolayer Electrocatalysts for CO2 Electroreduction","authors":"Xuemin An, Deren Yang","doi":"10.1039/d4nr04109g","DOIUrl":"https://doi.org/10.1039/d4nr04109g","url":null,"abstract":"Electrocatalytic carbon dioxide reduction reaction (CO2RR) is an attractive method for converting atmospheric CO2 into value-added chemicals and fuels. In order to overcome the low efficiency and durability that hinder its practical application, a significant amount of research has been dedicated to designing novel catalysts at the nanoscale and even the atomic scale. Two-dimensional (2D) monolayer materials inherit the merits of both 2D materials and single-atom materials. Through bridging the gap between heterogeneous and homogeneous catalysis, 2D monolayer materials exhibit great potential in CO2RR due to the unique structural/electronic properties, high atom utilization , low mass transfer resistance and uniform active sites. Here, we systematically overview the development and application of 2D monolayer catalysts for electrocatalytic CO2RR. Firstly, an overview of the CO2RR technology is presented. Subsequently, a comprehensive discussion is undertaken on various types of 2D monolayer electrocatalysts, such as 2D graphene-based materials, 2D monolayer metal-organic frameworks (MOFs), 2D monolayer covalent organic frameworks (COFs) and 2D monolayer metal-based materials. Their respective electrocatalytic performances are also systematically analyzed. More importantly, novel perspectives on the primary challenges and opportunities associated with the utilization of 2D monolayer materials in CO2RR are presented. Achieving high-quality 2D monolayer materials and producing high-selective multi-carbon products remains the two major challenges in the design, synthesis and appliaction of 2D monolayer electrocatalysts. Addressing these synthesis-related and performance-related issues is sigificant for the progression and practical utilization of 2D monolayer materials in CO₂RR.","PeriodicalId":92,"journal":{"name":"Nanoscale","volume":"35 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142935369","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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