The inevitable oxidation of nickel-metal-based catalysts exposed to the air will lead to instability and poor reproducibility of a catalytic interface, which is usually ignored and greatly hinders their application for the catalysis of alkaline hydrogen oxidation. The details on the formation of a world-class nickel-based HOR catalyst Ni3-MoOx/C-500 are reported via an interfacial reconstruction triggered by passive oxidation upon air exposure. Interfacial reconstruction, initiated with various Ni-Mo metal ratios and annealing temperature, can fine-tune the Ni-Mo interface with an increased work function and a reduced d-band center. The optimized Ni3-MoOx/C exhibits a record high mass activity of 102.8 mA mgNi-1, a top-level exchange current density of 76.5 µA cmNi-2, and exceptional resistance to CO poisoning at 1000 ppm CO for hours. The catalyzed alkaline exchange membrane fuel cell exhibits a maximum power output of 600 mW cm-2 and excellent stability, ranking it as one of the most active non-precious metals HOR catalysts to date.
镍金属基催化剂暴露在空气中不可避免地会发生氧化,从而导致催化界面不稳定且重现性差,这一点通常被忽视,并极大地阻碍了其在碱性氢氧化催化中的应用。本报告详细介绍了世界级镍基氢氧化催化剂 Ni3-MoOx/C-500 在暴露于空气中时由被动氧化引发的界面重构。通过不同的镍-钼金属比例和退火温度进行界面重构,可对镍-钼界面进行微调,从而提高做功函数并降低 d 带中心。优化后的 Ni3-MoOx/C 的质量活性达到了创纪录的 102.8 mA mgNi-1,交换电流密度达到了顶级水平 76.5 µA cmNi-2,并且在 1000 ppm CO 的条件下具有超强的抗 CO 中毒能力。这种催化碱性交换膜燃料电池的最大功率输出为 600 mW cm-2,稳定性极佳,是迄今为止最活跃的非贵金属 HOR 催化剂之一。
{"title":"Enhancement of Catalytic Activity via Inevitable Reconstruction of the Ni-Mo Interface for Alkaline Hydrogen Oxidation.","authors":"Xiaoyun Song, Qimei Yang, Zebi Chen, Kaisheng Zou, Zhenyang Xie, Wei Ding, Zidong Wei","doi":"10.1002/smll.202402701","DOIUrl":"10.1002/smll.202402701","url":null,"abstract":"<p><p>The inevitable oxidation of nickel-metal-based catalysts exposed to the air will lead to instability and poor reproducibility of a catalytic interface, which is usually ignored and greatly hinders their application for the catalysis of alkaline hydrogen oxidation. The details on the formation of a world-class nickel-based HOR catalyst Ni<sub>3</sub>-MoO<sub>x</sub>/C-500 are reported via an interfacial reconstruction triggered by passive oxidation upon air exposure. Interfacial reconstruction, initiated with various Ni-Mo metal ratios and annealing temperature, can fine-tune the Ni-Mo interface with an increased work function and a reduced d-band center. The optimized Ni<sub>3</sub>-MoO<sub>x</sub>/C exhibits a record high mass activity of 102.8 mA mg<sub>Ni</sub> <sup>-1</sup>, a top-level exchange current density of 76.5 µA cm<sub>Ni</sub> <sup>-2</sup>, and exceptional resistance to CO poisoning at 1000 ppm CO for hours. The catalyzed alkaline exchange membrane fuel cell exhibits a maximum power output of 600 mW cm<sup>-2</sup> and excellent stability, ranking it as one of the most active non-precious metals HOR catalysts to date.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141316303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-03-27DOI: 10.1002/smll.202306653
Inyoung Jang, Anna Hankin, Zheng Xie, Stephen J Skinner, Geoff H Kelsall
Increasing densities of reaction sites for gaseous reactants in solid oxide electrochemical reactors (SOERs), is a key strategy for achieving enhanced performance in either fuel cell or electrolysis modes. Fabrication of 3D structured components in SOERs can enhance those densities of reaction sites, which is achieved by 3D inkjet printing with high reproducibility, having developed inks with appropriate properties. First, the effects of pillar geometries on SOER performances are predicted through numerical simulations, enabling subsequent 3D printing to focus on the more effective geometries. Herein, the study reports the results of experimental validation of those predictions by evaluating the electrochemical performances of cells with various heights of 3D inkjet-printed Ni(O)- yttria stabilized zirconia (YSZ) pillars and YSZ pillars. Those measurements prove that increasing pillar heights generally increases SOER peak power densities in fuel cell mode and increased current densities at the thermoneutral potential (1.285 V) in steam electrolysis mode, as predicted by simulations. With increasing pillar heights, more limitations in performance enhancement are found with YSZ electrolyte pillars than with Ni-YSZ pillars, again as predicted by simulations. The subsequent microstructural analysis of Ni-YSZ pillars proves the suitability of the Ni(O)-YSZ composite particle ink formulation and the reliability of 3D printing.
{"title":"Structural Effects of 3D Inkjet-Printed Ni(O)-YSZ Pillared Electrodes on Performances of Solid Oxide Electrochemical Reactors.","authors":"Inyoung Jang, Anna Hankin, Zheng Xie, Stephen J Skinner, Geoff H Kelsall","doi":"10.1002/smll.202306653","DOIUrl":"10.1002/smll.202306653","url":null,"abstract":"<p><p>Increasing densities of reaction sites for gaseous reactants in solid oxide electrochemical reactors (SOERs), is a key strategy for achieving enhanced performance in either fuel cell or electrolysis modes. Fabrication of 3D structured components in SOERs can enhance those densities of reaction sites, which is achieved by 3D inkjet printing with high reproducibility, having developed inks with appropriate properties. First, the effects of pillar geometries on SOER performances are predicted through numerical simulations, enabling subsequent 3D printing to focus on the more effective geometries. Herein, the study reports the results of experimental validation of those predictions by evaluating the electrochemical performances of cells with various heights of 3D inkjet-printed Ni(O)- yttria stabilized zirconia (YSZ) pillars and YSZ pillars. Those measurements prove that increasing pillar heights generally increases SOER peak power densities in fuel cell mode and increased current densities at the thermoneutral potential (1.285 V) in steam electrolysis mode, as predicted by simulations. With increasing pillar heights, more limitations in performance enhancement are found with YSZ electrolyte pillars than with Ni-YSZ pillars, again as predicted by simulations. The subsequent microstructural analysis of Ni-YSZ pillars proves the suitability of the Ni(O)-YSZ composite particle ink formulation and the reliability of 3D printing.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140292280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-05-27DOI: 10.1002/smll.202400970
Min Li, Xin Zhou, Dandan Han, Qi Zhang, Xiaodong Li, Hongzhen Li, Junbo Gong
The fabrication of materials with hierarchical structures has garnered great interest, owing to the potential for significantly enhancing their functions. Herein, a strategy of coupling molecular solvation and crystal growth is presented to fabricate porous spherulites of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), an important energetic material. With the addition of polyvinylpyrrolidone in the antisolvent crystallization, the metastable solvate of CL-20 is formed and grows spherulitically, and spontaneously desolvates to obtain the porous spherulite when filtration, in which the characteristic peak of the nitro group of CL-20 shifts detected by the in situ micro-confocal Raman spectroscopy. The effect of polyvinylpyrrolidone is thought to induce the solvation of CL-20, confirmed by density functional theory calculations, meanwhile acting on the (020) face of CL-20 to trigger spherulitic growth, demonstrated through infrared spectroscopy and Rietveld refinement of powder X-ray diffraction. Moreover, compared to common CL-20 crystals, porous spherulites exhibit enhanced combustion with increases of 6.24% in peak pressure, 40.21% in pressurization rate, and 9.63% in pressure duration effect, indicating the capability of hierarchical structures to boost the energy release of energetic crystals. This work demonstrates a new route via solvation-growth coupling to construct hierarchical structures for organic crystals and provides insight into the structure-property relations for material design.
{"title":"Constructing Porous Energetic Spherulites via Solvation-Growth Coupling for Enhanced Combustion.","authors":"Min Li, Xin Zhou, Dandan Han, Qi Zhang, Xiaodong Li, Hongzhen Li, Junbo Gong","doi":"10.1002/smll.202400970","DOIUrl":"10.1002/smll.202400970","url":null,"abstract":"<p><p>The fabrication of materials with hierarchical structures has garnered great interest, owing to the potential for significantly enhancing their functions. Herein, a strategy of coupling molecular solvation and crystal growth is presented to fabricate porous spherulites of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), an important energetic material. With the addition of polyvinylpyrrolidone in the antisolvent crystallization, the metastable solvate of CL-20 is formed and grows spherulitically, and spontaneously desolvates to obtain the porous spherulite when filtration, in which the characteristic peak of the nitro group of CL-20 shifts detected by the in situ micro-confocal Raman spectroscopy. The effect of polyvinylpyrrolidone is thought to induce the solvation of CL-20, confirmed by density functional theory calculations, meanwhile acting on the (020) face of CL-20 to trigger spherulitic growth, demonstrated through infrared spectroscopy and Rietveld refinement of powder X-ray diffraction. Moreover, compared to common CL-20 crystals, porous spherulites exhibit enhanced combustion with increases of 6.24% in peak pressure, 40.21% in pressurization rate, and 9.63% in pressure duration effect, indicating the capability of hierarchical structures to boost the energy release of energetic crystals. This work demonstrates a new route via solvation-growth coupling to construct hierarchical structures for organic crystals and provides insight into the structure-property relations for material design.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141154054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Strain engineering has been widely used to optimize platinum-based oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs). PtM3 (M is base metals), a well-known high-compressive-strain intermetallic alloy, shows promise as a low platinum ORR catalyst due to high intrinsic activity. However, during the alloying of Pt with a threefold amount of M, a notable phase separation between Pt and M may occur, with M particles rapidly sintering while Pt particles grow slowly, posing a challenge in achieving a well-defined PtM3 intermetallic alloy. Here, an entropy-driven Ostwald ripening reversal phenomenon is discovered that enables the synthesis of small-sized Pt(FeCoNiCu)3 intermetallic ORR catalysts. High entropy promotes the thermodynamic driving force for the alloying Pt with M, which triggers the Ostwald ripening reversal of sintered FeCoNiCu particles and facilitates the formation of uniform Pt(FeCoNiCu)3 intermetallic catalysts. The prepared Pt(FeCoNiCu)3 catalysts exhibit a high specific activity of 3.82 mA cm-2, along with a power density of ≈1.3 W cm-2 at 0.67 V and 94 °C with a cathode Pt loading of 0.1 mg cm-2 in H2-air fuel cell.
应变工程已被广泛用于优化质子交换膜燃料电池(PEMFC)的铂基氧还原反应(ORR)催化剂。PtM3(M 为贱金属)是一种著名的高抗压应变金属间合金,由于具有较高的内在活性,有望成为一种低铂 ORR 催化剂。然而,在铂与三倍量 M 的合金化过程中,铂和 M 之间可能会发生明显的相分离,M 颗粒会迅速烧结,而铂颗粒则会缓慢生长,这给获得定义明确的 PtM3 金属间合金带来了挑战。本文发现了一种熵驱动的奥斯特瓦尔德熟化逆转现象,这种现象使得合成小尺寸的 Pt(FeCoNiCu)3 金属间 ORR 催化剂成为可能。高熵促进了铂与 M 合金的热力学驱动力,引发了烧结铁钴镍铜颗粒的奥斯特瓦尔德熟化逆转,促进了均匀的 Pt(FeCoNiCu)3 金属间催化剂的形成。所制备的 Pt(FeCoNiCu)3 催化剂具有 3.82 mA cm-2 的高比活度,在 0.67 V、94 °C、阴极铂负载量为 0.1 mg cm-2 的 H2- 空气燃料电池中,功率密度≈1.3 W cm-2。
{"title":"Entropy-Driven Ostwald Ripening Reversal Promotes the Formation of Low-Platinum Intermetallic Fuel Cell Catalysts.","authors":"Shuo-Bin Li, Peng Yin, Cong Xu, Kun-Ze Xue, Yuan Kong, Ming Zuo, Wan-Qun Zhang, Hai-Wei Liang","doi":"10.1002/smll.202401134","DOIUrl":"10.1002/smll.202401134","url":null,"abstract":"<p><p>Strain engineering has been widely used to optimize platinum-based oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs). PtM<sub>3</sub> (M is base metals), a well-known high-compressive-strain intermetallic alloy, shows promise as a low platinum ORR catalyst due to high intrinsic activity. However, during the alloying of Pt with a threefold amount of M, a notable phase separation between Pt and M may occur, with M particles rapidly sintering while Pt particles grow slowly, posing a challenge in achieving a well-defined PtM<sub>3</sub> intermetallic alloy. Here, an entropy-driven Ostwald ripening reversal phenomenon is discovered that enables the synthesis of small-sized Pt(FeCoNiCu)<sub>3</sub> intermetallic ORR catalysts. High entropy promotes the thermodynamic driving force for the alloying Pt with M, which triggers the Ostwald ripening reversal of sintered FeCoNiCu particles and facilitates the formation of uniform Pt(FeCoNiCu)<sub>3</sub> intermetallic catalysts. The prepared Pt(FeCoNiCu)<sub>3</sub> catalysts exhibit a high specific activity of 3.82 mA cm<sup>-2</sup>, along with a power density of ≈1.3 W cm<sup>-2</sup> at 0.67 V and 94 °C with a cathode Pt loading of 0.1 mg cm<sup>-2</sup> in H<sub>2</sub>-air fuel cell.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141178400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-06-03DOI: 10.1002/smll.202312046
Yuzhou Deng, Guanbin Gao, Liangchong Yu, Zijun Zhang, Bin Zhang, Hu Li, Xinyu Zhang, Lei Shen, Taolei Sun
Accurate construction of artificial nano-chaperones' structure is crucial for precise regulation of protein conformational transformation, facilitating effective treatment of proteopathy. However, how the ligand-anchors of nano-chaperones affect the spatial conformational changes in proteins remains unclear, limiting the development of efficient nano-chaperones. In this study, three types of gold nanoparticles (AuNPs) with different core/ligands interface anchor structures (Au─NH─R, Au─S─R, and Au─C≡C─R, R = benzoic acid) are synthesized as an ideal model to investigate the effect of interfacial anchors on Aβ and amylin fibrillization. Computational results revealed that the distinct interfacial anchors imparted diverse distributions of electrostatic potential on the nanointerface and core/ligands bond strength of AuNPs, leading to differential interactions with amyloid peptides. Experimental results demonstrated that all three types of AuNPs exhibit site-specific inhibitory effects on Aβ40 fibrillization due to preferential binding. For amylin, amino-anchored AuNPs demonstrate strong adsorption to multiple sites on amylin and effectively inhibit fibrillization. Conversely, thiol- and alkyne-anchored AuNPs adsorb at the head region of amylin, promoting folding and fibrillization. This study not only provided molecular insights into how core/ligands interfacial anchors of nanomaterials induce spatial conformational changes in amyloid peptides but also offered guidance for precisely engineering artificial-chaperones' nanointerfaces to regulate the conformational transformation of proteins.
{"title":"Engineering Core/Ligands Interfacial Anchors of Nanoparticles for Efficiently Inhibiting Both Aβ and Amylin Fibrillization.","authors":"Yuzhou Deng, Guanbin Gao, Liangchong Yu, Zijun Zhang, Bin Zhang, Hu Li, Xinyu Zhang, Lei Shen, Taolei Sun","doi":"10.1002/smll.202312046","DOIUrl":"10.1002/smll.202312046","url":null,"abstract":"<p><p>Accurate construction of artificial nano-chaperones' structure is crucial for precise regulation of protein conformational transformation, facilitating effective treatment of proteopathy. However, how the ligand-anchors of nano-chaperones affect the spatial conformational changes in proteins remains unclear, limiting the development of efficient nano-chaperones. In this study, three types of gold nanoparticles (AuNPs) with different core/ligands interface anchor structures (Au─NH─R, Au─S─R, and Au─C≡C─R, R = benzoic acid) are synthesized as an ideal model to investigate the effect of interfacial anchors on Aβ and amylin fibrillization. Computational results revealed that the distinct interfacial anchors imparted diverse distributions of electrostatic potential on the nanointerface and core/ligands bond strength of AuNPs, leading to differential interactions with amyloid peptides. Experimental results demonstrated that all three types of AuNPs exhibit site-specific inhibitory effects on Aβ<sub>40</sub> fibrillization due to preferential binding. For amylin, amino-anchored AuNPs demonstrate strong adsorption to multiple sites on amylin and effectively inhibit fibrillization. Conversely, thiol- and alkyne-anchored AuNPs adsorb at the head region of amylin, promoting folding and fibrillization. This study not only provided molecular insights into how core/ligands interfacial anchors of nanomaterials induce spatial conformational changes in amyloid peptides but also offered guidance for precisely engineering artificial-chaperones' nanointerfaces to regulate the conformational transformation of proteins.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141198645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-06-08DOI: 10.1002/smll.202402613
Dechao Chen, Rohan J Hudson, Cheng Tang, Qiang Sun, Jeffery R Harmer, Miaomiao Liu, Mehri Ghasemi, Xiaomin Wen, Zixuan Liu, Wei Peng, Xuecheng Yan, Bruce Cowie, Yongsheng Gao, Colin L Raston, Aijun Du, Trevor A Smith, Qin Li
Methanol is not only a promising liquid hydrogen carrier but also an important feedstock chemical for chemical synthesis. Catalyst design is vital for enabling the reactions to occur under ambient conditions. This study reports a new class of van der Waals heterojunction photocatalyst, which is synthesized by hot-injection method, whereby carbon dots (CDs) are grown in situ on ZnSe nanoplatelets (NPLs), i.e., metal chalcogenide quantum wells. The resultant organic-inorganic hybrid nanoparticles, CD-NPLs, are able to perform methanol dehydrogenation through CH splitting. The heterostructure has enabled light-induced charge transfer from the CDs into the NPLs occurring on a sub-nanosecond timescale, with charges remaining separated across the CD-NPLs heterostructure for longer than 500 ns. This resulted in significantly heightened H2 production rate of 107 µmole·g-1·h-1 and enhanced photocurrent density up to 34 µA cm-2 at 1 V bias potential. EPR and NMR analyses confirmed the occurrence of α-CH splitting and CC coupling. The novel CD-based organic-inorganic semiconductor heterojunction is poised to enable the discovery of a host of new nano-hybrid photocatalysts with full tunability in the band structure, charge transfer, and divergent surface chemistry for guiding photoredox pathways and accelerating reaction rates.
{"title":"Colloidal Synthesis of Carbon Dot-ZnSe Nanoplatelet Van der Waals Heterostructures for Boosting Photocatalytic Generation of Methanol-Storable Hydrogen.","authors":"Dechao Chen, Rohan J Hudson, Cheng Tang, Qiang Sun, Jeffery R Harmer, Miaomiao Liu, Mehri Ghasemi, Xiaomin Wen, Zixuan Liu, Wei Peng, Xuecheng Yan, Bruce Cowie, Yongsheng Gao, Colin L Raston, Aijun Du, Trevor A Smith, Qin Li","doi":"10.1002/smll.202402613","DOIUrl":"10.1002/smll.202402613","url":null,"abstract":"<p><p>Methanol is not only a promising liquid hydrogen carrier but also an important feedstock chemical for chemical synthesis. Catalyst design is vital for enabling the reactions to occur under ambient conditions. This study reports a new class of van der Waals heterojunction photocatalyst, which is synthesized by hot-injection method, whereby carbon dots (CDs) are grown in situ on ZnSe nanoplatelets (NPLs), i.e., metal chalcogenide quantum wells. The resultant organic-inorganic hybrid nanoparticles, CD-NPLs, are able to perform methanol dehydrogenation through CH splitting. The heterostructure has enabled light-induced charge transfer from the CDs into the NPLs occurring on a sub-nanosecond timescale, with charges remaining separated across the CD-NPLs heterostructure for longer than 500 ns. This resulted in significantly heightened H<sub>2</sub> production rate of 107 µmole·g<sup>-1</sup>·h<sup>-1</sup> and enhanced photocurrent density up to 34 µA cm<sup>-2</sup> at 1 V bias potential. EPR and NMR analyses confirmed the occurrence of α-CH splitting and CC coupling. The novel CD-based organic-inorganic semiconductor heterojunction is poised to enable the discovery of a host of new nano-hybrid photocatalysts with full tunability in the band structure, charge transfer, and divergent surface chemistry for guiding photoredox pathways and accelerating reaction rates.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141292871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-07-05DOI: 10.1002/smll.202401772
Jie Wang, Ping Li, Renshuai Zhang, Miao Zhang, Chao Wang, Kaihua Zhao, Jing Wang, Ning Wang, Dongming Xing
Flexibility of nanomaterials is challenging but worthy to tune for biomedical applications. Biocompatible silica nanomaterials are under extensive exploration but are rarely observed to exhibit flexibility despite the polymeric nature. Herein, a facile one-step route is reported to ultrathin flexible silica nanosheets (NSs), whose low thickness and high diameter-to-thickness ratio enables folding. Thickness and diameter can be readily tuned to enable controlled flexibility. Mechanism study reveals that beyond the commonly used surfactant, the "uncommon" one bearing two hydrophobic tails play a guiding role in producing sheeted/layered/shelled structures, while addition of ethanol appropriately relieved the strong interfacial tension of the assembled surfactants, which will otherwise produce large curled sheeted structures. With these ultrathin NSs, it is further shown that the cellular preference for particle shape and rigidity is highly dependent on surface chemistry of nanoparticles: under high particle-cell affinity, NSs, and especially the flexible ones will be preferred by mammalian cells for internalization or attachment, while this preference is basically invalid when the affinity is low. Therefore, properties of the ultrathin silica NSs can be effectively expanded and empowered by surface chemistry to realize improved bio-sensing or drug delivery.
{"title":"Ultrathin Flexible Silica Nanosheets with Surface Chemistry-Modulated Affinity to Mammalian Cells.","authors":"Jie Wang, Ping Li, Renshuai Zhang, Miao Zhang, Chao Wang, Kaihua Zhao, Jing Wang, Ning Wang, Dongming Xing","doi":"10.1002/smll.202401772","DOIUrl":"10.1002/smll.202401772","url":null,"abstract":"<p><p>Flexibility of nanomaterials is challenging but worthy to tune for biomedical applications. Biocompatible silica nanomaterials are under extensive exploration but are rarely observed to exhibit flexibility despite the polymeric nature. Herein, a facile one-step route is reported to ultrathin flexible silica nanosheets (NSs), whose low thickness and high diameter-to-thickness ratio enables folding. Thickness and diameter can be readily tuned to enable controlled flexibility. Mechanism study reveals that beyond the commonly used surfactant, the \"uncommon\" one bearing two hydrophobic tails play a guiding role in producing sheeted/layered/shelled structures, while addition of ethanol appropriately relieved the strong interfacial tension of the assembled surfactants, which will otherwise produce large curled sheeted structures. With these ultrathin NSs, it is further shown that the cellular preference for particle shape and rigidity is highly dependent on surface chemistry of nanoparticles: under high particle-cell affinity, NSs, and especially the flexible ones will be preferred by mammalian cells for internalization or attachment, while this preference is basically invalid when the affinity is low. Therefore, properties of the ultrathin silica NSs can be effectively expanded and empowered by surface chemistry to realize improved bio-sensing or drug delivery.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141533000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-06-06DOI: 10.1002/smll.202403065
Jinghua Quan, Haoxiang Lin, Hongyan Li
In the research report of cathode of potassium ion battery, Mn-based layered structural oxides have attracted the researcher's attention because of its good energy density and high specific rate capacity. However, the Jahn-Teller effect is the main limiting factor for their development. It leads to the expansion and deactivation of Mn-based layered metal oxides during cycling for a long time. Therefore, mitigation of the Jahn-Teller effect is considered a useful measure to enhance the electrochemical capability of Mn-based layered oxide. In this paper, an R3m-type K0.4Mn0.7Co0.25Zn0.05O2 cathode material is designed through a Zn doping strategy. X-ray diffraction techniques and electrochemical tests verified that the Jahn-Teller effect is effectively mitigated. High performance is achieved in the rate capacity test with 113 mAh g-1 at 50 mA g-1. Comparison with similar materials in recent years has demonstrated its superiority, leading rate performance among Mn-based metal oxides reported in recent years. The practical feasibility is verified in the assembled full cell with soft carbon in anode materials and K0.4Mn0.7Co0.25Zn0.05O2 as cathode. In the full cell rate test, 104.8 mAh g-1 discharging capacity is achieved at 50 mA g-1 current density.
在钾离子电池阴极的研究报告中,锰基层结构氧化物因其良好的能量密度和较高的比速率容量而引起了研究人员的关注。然而,贾恩-泰勒效应是限制其发展的主要因素。它导致锰基层金属氧化物在长时间循环过程中膨胀和失活。因此,缓解 Jahn-Teller 效应被认为是提高锰基层状氧化物电化学能力的有效措施。本文通过 Zn 掺杂策略设计了一种 R3m 型 K0.4Mn0.7Co0.25Zn0.05O2 阴极材料。X 射线衍射技术和电化学测试验证了 Jahn-Teller 效应得到了有效缓解。在速率容量测试中,在 50 mA g-1 的条件下达到了 113 mAh g-1 的高性能。与近年报道的同类材料相比,它的性能更加优越,在近年来报道的锰基金属氧化物中,它的速率性能遥遥领先。在以软碳为阳极材料、K0.4Mn0.7Co0.25Zn0.05O2 为阴极的组装全电池中验证了其实用可行性。在全电池速率测试中,在 50 mA g-1 的电流密度下实现了 104.8 mAh g-1 的放电容量。
{"title":"Zn Doping Strategy to Suppress the Jahn-Teller Effect to Stabilize Mn-Based Layered Oxide Cathode toward High-Performance Potassium Ion Batteries.","authors":"Jinghua Quan, Haoxiang Lin, Hongyan Li","doi":"10.1002/smll.202403065","DOIUrl":"10.1002/smll.202403065","url":null,"abstract":"<p><p>In the research report of cathode of potassium ion battery, Mn-based layered structural oxides have attracted the researcher's attention because of its good energy density and high specific rate capacity. However, the Jahn-Teller effect is the main limiting factor for their development. It leads to the expansion and deactivation of Mn-based layered metal oxides during cycling for a long time. Therefore, mitigation of the Jahn-Teller effect is considered a useful measure to enhance the electrochemical capability of Mn-based layered oxide. In this paper, an R<sub>3</sub>m-type K<sub>0.4</sub>Mn<sub>0.7</sub>Co<sub>0.25</sub>Zn<sub>0.05</sub>O<sub>2</sub> cathode material is designed through a Zn doping strategy. X-ray diffraction techniques and electrochemical tests verified that the Jahn-Teller effect is effectively mitigated. High performance is achieved in the rate capacity test with 113 mAh g<sup>-1</sup> at 50 mA g<sup>-1</sup>. Comparison with similar materials in recent years has demonstrated its superiority, leading rate performance among Mn-based metal oxides reported in recent years. The practical feasibility is verified in the assembled full cell with soft carbon in anode materials and K<sub>0.4</sub>Mn<sub>0.7</sub>Co<sub>0.25</sub>Zn<sub>0.05</sub>O<sub>2</sub> as cathode. In the full cell rate test, 104.8 mAh g<sup>-1</sup> discharging capacity is achieved at 50 mA g<sup>-1</sup> current density.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141282519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-06-08DOI: 10.1002/smll.202402432
Dhanush Patil, Siying Liu, Dharneedar Ravichandran, Sri Vaishnavi Thummalapalli, Yuxiang Zhu, Tengteng Tang, Yuval Golan, Guillaume Miquelard-Garnier, Amir Asadi, Xiangjia Li, Xiangfan Chen, Kenan Song
This paper presents a scalable and straightforward technique for the immediate patterning of liquid metal/polymer composites via multiphase 3D printing. Capitalizing on the polymer's capacity to confine liquid metal (LM) into diverse patterns. The interplay between distinctive fluidic properties of liquid metal and its self-passivating oxide layer within an oxidative environment ensures a resilient interface with the polymer matrix. This study introduces an inventive approach for achieving versatile patterns in eutectic gallium indium (EGaIn), a gallium alloy. The efficacy of pattern formation hinges on nozzle's design and internal geometry, which govern multiphase interaction. The interplay between EGaIn and polymer within the nozzle channels, regulated by variables such as traverse speed and material flow pressure, leads to periodic patterns. These patterns, when encapsulated within a dielectric polymer polyvinyl alcohol (PVA), exhibit an augmented inherent capacitance in capacitor assemblies. This discovery not only unveils the potential for cost-effective and highly sensitive capacitive pressure sensors but also underscores prospective applications of these novel patterns in precise motion detection, including heart rate monitoring, and comprehensive analysis of gait profiles. The amalgamation of advanced materials and intricate patterning techniques presents a transformative prospect in the domains of wearable sensing and comprehensive human motion analysis.
{"title":"Versatile Patterning of Liquid Metal via Multiphase 3D Printing.","authors":"Dhanush Patil, Siying Liu, Dharneedar Ravichandran, Sri Vaishnavi Thummalapalli, Yuxiang Zhu, Tengteng Tang, Yuval Golan, Guillaume Miquelard-Garnier, Amir Asadi, Xiangjia Li, Xiangfan Chen, Kenan Song","doi":"10.1002/smll.202402432","DOIUrl":"10.1002/smll.202402432","url":null,"abstract":"<p><p>This paper presents a scalable and straightforward technique for the immediate patterning of liquid metal/polymer composites via multiphase 3D printing. Capitalizing on the polymer's capacity to confine liquid metal (LM) into diverse patterns. The interplay between distinctive fluidic properties of liquid metal and its self-passivating oxide layer within an oxidative environment ensures a resilient interface with the polymer matrix. This study introduces an inventive approach for achieving versatile patterns in eutectic gallium indium (EGaIn), a gallium alloy. The efficacy of pattern formation hinges on nozzle's design and internal geometry, which govern multiphase interaction. The interplay between EGaIn and polymer within the nozzle channels, regulated by variables such as traverse speed and material flow pressure, leads to periodic patterns. These patterns, when encapsulated within a dielectric polymer polyvinyl alcohol (PVA), exhibit an augmented inherent capacitance in capacitor assemblies. This discovery not only unveils the potential for cost-effective and highly sensitive capacitive pressure sensors but also underscores prospective applications of these novel patterns in precise motion detection, including heart rate monitoring, and comprehensive analysis of gait profiles. The amalgamation of advanced materials and intricate patterning techniques presents a transformative prospect in the domains of wearable sensing and comprehensive human motion analysis.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141292878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electrocatalysis is a very attractive way to achieve a sustainable carbon cycle by converting CO2 into organic fuels and feedstocks. Therefore, it is crucial to design advanced electrocatalysts by understanding the reaction mechanism of electrochemical CO2 reduction reaction (eCO2RR) with multiple electron transfers. Among electrocatalysts, dual-atom catalysts (DACs) are promising candidates due to their distinct electronic structures and extremely high atomic utilization efficiency. Herein, the eCO2RR mechanism and the identification of intermediates using advanced characterization techniques, with a particular focus on regulating the critical intermediates are systematically summarized. Further, the insightful understanding of the functionality of DACs originates from the variable metrics of electronic structures including orbital structure, charge distribution, and electron spin state, which influences the active sites and critical intermediates in eCO2RR processes. Based on the intrinsic relationship between variable metrics and critical intermediates, the optimized strategies of DACs are summarized containing the participation of synergistic atoms, engineering of the atomic coordination environment, regulation of the diversity of central metal atoms, and modulation of metal-support interaction. Finally, the challenges and future opportunities of atomically dispersed catalysts for eCO2RR processes are discussed.
{"title":"Regulating the Critical Intermediates of Dual-Atom Catalysts for CO<sub>2</sub> Electroreduction.","authors":"Mengyang Zhang, Dingyang Zhou, Xueqin Mu, Dingsheng Wang, Suli Liu, Zhihui Dai","doi":"10.1002/smll.202402050","DOIUrl":"10.1002/smll.202402050","url":null,"abstract":"<p><p>Electrocatalysis is a very attractive way to achieve a sustainable carbon cycle by converting CO<sub>2</sub> into organic fuels and feedstocks. Therefore, it is crucial to design advanced electrocatalysts by understanding the reaction mechanism of electrochemical CO<sub>2</sub> reduction reaction (eCO<sub>2</sub>RR) with multiple electron transfers. Among electrocatalysts, dual-atom catalysts (DACs) are promising candidates due to their distinct electronic structures and extremely high atomic utilization efficiency. Herein, the eCO<sub>2</sub>RR mechanism and the identification of intermediates using advanced characterization techniques, with a particular focus on regulating the critical intermediates are systematically summarized. Further, the insightful understanding of the functionality of DACs originates from the variable metrics of electronic structures including orbital structure, charge distribution, and electron spin state, which influences the active sites and critical intermediates in eCO<sub>2</sub>RR processes. Based on the intrinsic relationship between variable metrics and critical intermediates, the optimized strategies of DACs are summarized containing the participation of synergistic atoms, engineering of the atomic coordination environment, regulation of the diversity of central metal atoms, and modulation of metal-support interaction. Finally, the challenges and future opportunities of atomically dispersed catalysts for eCO<sub>2</sub>RR processes are discussed.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141154149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}