Xiaohan Li,Shuo Chen,Yuao Wei,Chao Dong,Ziyi Zhang,Zhou Ge,Wenjing Liu,Yu Fu
The electrochemical nitrogen reduction reaction (NRR) offers a sustainable pathway for ammonia synthesis under ambient conditions. Among these, vacancy engineering has emerged as an effective approach to accelerate nitrogen-to-ammonia conversion and enhance electrocatalytic performance. However, the controllable synthesis of catalysts with precise cation vacancy concentrations remains a significant challenge. In this study, we address this by employing a combined thermal treatment and plasma approach to fabricate copper selenide nanosheets with precisely tuned copper vacancy (VCu) concentrations. The resulting p-Cu1.8Se/Cu2Se/C-5 catalyst, possessing the highest VCu concentration, demonstrated superior NRR activity, achieving an NH3 production rate of 21.81 μg h-1 mgcat.-1 at -0.7 V vs the reversible hydrogen electrode (RHE), a value more than 3-fold higher than that of its vacancy-free counterpart. These results indicate that VCu sites serve as active centers that optimize nitrogen adsorption and activation, thereby significantly lowering the energy barrier of the rate-determining step. This work provides a new avenue for designing next-generation, high-performance NRR electrocatalysts through precise defect engineering.
{"title":"Copper Selenide Nanosheet with Adjustable Cation Vacancy for Boosting Nitrogen Electroreduction.","authors":"Xiaohan Li,Shuo Chen,Yuao Wei,Chao Dong,Ziyi Zhang,Zhou Ge,Wenjing Liu,Yu Fu","doi":"10.1021/acsami.5c20585","DOIUrl":"https://doi.org/10.1021/acsami.5c20585","url":null,"abstract":"The electrochemical nitrogen reduction reaction (NRR) offers a sustainable pathway for ammonia synthesis under ambient conditions. Among these, vacancy engineering has emerged as an effective approach to accelerate nitrogen-to-ammonia conversion and enhance electrocatalytic performance. However, the controllable synthesis of catalysts with precise cation vacancy concentrations remains a significant challenge. In this study, we address this by employing a combined thermal treatment and plasma approach to fabricate copper selenide nanosheets with precisely tuned copper vacancy (VCu) concentrations. The resulting p-Cu1.8Se/Cu2Se/C-5 catalyst, possessing the highest VCu concentration, demonstrated superior NRR activity, achieving an NH3 production rate of 21.81 μg h-1 mgcat.-1 at -0.7 V vs the reversible hydrogen electrode (RHE), a value more than 3-fold higher than that of its vacancy-free counterpart. These results indicate that VCu sites serve as active centers that optimize nitrogen adsorption and activation, thereby significantly lowering the energy barrier of the rate-determining step. This work provides a new avenue for designing next-generation, high-performance NRR electrocatalysts through precise defect engineering.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"1 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145711046","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}
Ingyu Yoo, Jinwoo Kim, Gwan-Hyoung Lee, Miyoung Kim
The transition from two-dimensional (2D) to three-dimensional (3D) layered systems has significantly expanded the research landscape for functional materials. Among these, polar layered materials with noncentrosymmetry, such as 3R-MoS2, 3R-WSe2, and In2Se3, are particularly intriguing due to their inherent structural asymmetry, which leads to exceptional properties, such as ferroelectricity, piezoelectricity, and nonlinear optical responses. However, precisely determining the layer-by-layer stacking sequence in multilayer polar materials remains a significant challenge. To address this challenge, we present a methodology that determines stacking sequences through an integrated analysis of multiple scattering signatures from the layered atomic arrangement, particularly the electron diffraction polarity arising from structural asymmetry. We demonstrate its capability in chemical vapor deposition (CVD)-grown WSe2 multilayers, a representative transition metal dichalcogenides (TMDs) with polar noncentrosymmetric stacking and sliding ferroelectricity, accurately identifying diverse stacking scenarios, such as mixed antiparallel and parallel arrangements and complicated structure, such as spiral with stacking faults. Comprehensive validation and comparative analysis by transmission electron microscopy (TEM), Kelvin probe force microscopy (KPFM), and low-frequency Raman spectroscopy confirm the reliability of this diffraction polarity-based technique and its ability to correlate stacking sequence with material properties. This methodology is broadly applicable to layered materials with intrinsically broken inversion symmetry, enabling automatic stacking determination and extending to complex architectures, such as twisted or heterostructural moiré systems. Our method provides a critical tool for probing polar layered materials, which are promising candidates for ferroelectricity, optoelectronics, and spintronics.
{"title":"Unraveling Diverse Stacking Sequence in CVD-Grown WSe<sub>2</sub> Multilayers via Electron Diffraction Polarity.","authors":"Ingyu Yoo, Jinwoo Kim, Gwan-Hyoung Lee, Miyoung Kim","doi":"10.1021/acsami.5c19002","DOIUrl":"https://doi.org/10.1021/acsami.5c19002","url":null,"abstract":"<p><p>The transition from two-dimensional (2D) to three-dimensional (3D) layered systems has significantly expanded the research landscape for functional materials. Among these, polar layered materials with noncentrosymmetry, such as 3R-MoS<sub>2</sub>, 3R-WSe<sub>2</sub>, and In<sub>2</sub>Se<sub>3</sub>, are particularly intriguing due to their inherent structural asymmetry, which leads to exceptional properties, such as ferroelectricity, piezoelectricity, and nonlinear optical responses. However, precisely determining the layer-by-layer stacking sequence in multilayer polar materials remains a significant challenge. To address this challenge, we present a methodology that determines stacking sequences through an integrated analysis of multiple scattering signatures from the layered atomic arrangement, particularly the electron diffraction polarity arising from structural asymmetry. We demonstrate its capability in chemical vapor deposition (CVD)-grown WSe<sub>2</sub> multilayers, a representative transition metal dichalcogenides (TMDs) with polar noncentrosymmetric stacking and sliding ferroelectricity, accurately identifying diverse stacking scenarios, such as mixed antiparallel and parallel arrangements and complicated structure, such as spiral with stacking faults. Comprehensive validation and comparative analysis by transmission electron microscopy (TEM), Kelvin probe force microscopy (KPFM), and low-frequency Raman spectroscopy confirm the reliability of this diffraction polarity-based technique and its ability to correlate stacking sequence with material properties. This methodology is broadly applicable to layered materials with intrinsically broken inversion symmetry, enabling automatic stacking determination and extending to complex architectures, such as twisted or heterostructural moiré systems. Our method provides a critical tool for probing polar layered materials, which are promising candidates for ferroelectricity, optoelectronics, and spintronics.</p>","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145720059","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}
Vitiligo is an autoimmune disorder characterized by the destruction of melanocytes, resulting in white skin patches that significantly affect patients’ social interactions. Current clinical interventions, including immunosuppressants, phototherapy, and transplantation, aim to restore pigmentation but often fail in distal areas or long-standing cases. Bioinspired melanin-like nanoparticles (NPs), such as polydopamine (PDA) NPs, are developed as synthetic analogs of eumelanin with antioxidative and immunomodulatory properties. Here, various melanin-like NPs are compared in terms of their physical characteristics and redox activities. Based on these findings, PDA NPs modified with polyethylene glycol (PEG), termed PDA@PEG NPs, are incorporated into dissolvable microneedle (MN) patches for transdermal delivery. In a vitiligo mouse model, these patches deliver NPs into the superficial dermis, where PDA@PEG NPs serve a dual role in promoting repigmentation: (1) they offer a brown-toned concealing effect to camouflage depigmented areas and (2) they alleviate oxidative stress and reduce CD8+ T cell infiltration. Mechanistically, the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling pathway is activated by PDA@PEG NPs. These findings support the potential of PDA@PEG/MN patches as a minimally invasive, multifunctional platform for accelerating repigmentation in vitiligo.
{"title":"Microneedle Patch Delivering Multifunctional Melanin-like Nanoparticles for Vitiligo Remission and Repigmentation","authors":"Zhaoting Jiang, Yuqi Zhou, Bo Wang, Chenhui He, Jia Zhang, Qi Wang, Ziwei Deng, Chunying Li, Zhe Jian","doi":"10.1021/acsami.5c11865","DOIUrl":"https://doi.org/10.1021/acsami.5c11865","url":null,"abstract":"Vitiligo is an autoimmune disorder characterized by the destruction of melanocytes, resulting in white skin patches that significantly affect patients’ social interactions. Current clinical interventions, including immunosuppressants, phototherapy, and transplantation, aim to restore pigmentation but often fail in distal areas or long-standing cases. Bioinspired melanin-like nanoparticles (NPs), such as polydopamine (PDA) NPs, are developed as synthetic analogs of eumelanin with antioxidative and immunomodulatory properties. Here, various melanin-like NPs are compared in terms of their physical characteristics and redox activities. Based on these findings, PDA NPs modified with polyethylene glycol (PEG), termed PDA@PEG NPs, are incorporated into dissolvable microneedle (MN) patches for transdermal delivery. In a vitiligo mouse model, these patches deliver NPs into the superficial dermis, where PDA@PEG NPs serve a dual role in promoting repigmentation: (1) they offer a brown-toned concealing effect to camouflage depigmented areas and (2) they alleviate oxidative stress and reduce CD8<sup>+</sup> T cell infiltration. Mechanistically, the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling pathway is activated by PDA@PEG NPs. These findings support the potential of PDA@PEG/MN patches as a minimally invasive, multifunctional platform for accelerating repigmentation in vitiligo.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"49 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145718217","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}
Buckypaper (BP), a self-supporting conductive thin film made from carbon nanotubes, is known for its ease of manufacture, excellent repeatability, and promising potential in the electronics field. However, challenges remain in balancing its mechanical strength and conductivity. In this study, we present a simple and effective one-pot synthesis method to fabricate highly conductive and mechanically robust BPs composed of a conjugated polymer (P1)–single-walled carbon nanotube (SWNT) complex and microcrystalline cellulose (MCC). P1, which features a self-immolative linker (SIL) between the polymer backbone and side chain, is used to disperse SWNTs in organic solvents. Upon treatment with tetra-n-butylammonium fluoride (TBAF), the insulating side chains of the polymer are removed to yield P0, which significantly enhances the conductivity of the resulting BP. However, this side chain removal weakens the mechanical strength of the BP. To address this trade-off, MCC was introduced as a mechanical reinforcing agent. Leveraging the good solubility of MCC in a TBAF/DMSO mixture, we developed a one-pot synthesis method to fabricate composite BPs with P0–SWNT complexes and MCC, using TBAF for both solubilization and side chain removal. The composite BPs exhibited improved mechanical properties and conductivity. Notably, a BP containing 42% P0–SWNT by weight demonstrated an optimal balance of strength (tensile modulus of 161 ± 10 MPa, yield point of 11 ± 2%) and conductivity (107 ± 4 S/m). This straightforward and scalable preparation method allows production of BPs with balanced mechanical and electrical properties that may be valuable for downstream applications.
{"title":"Cellulose-Reinforced Carbon Nanotube Buckypapers with Balanced Mechanical Strength and Conductivity","authors":"Xiao Yu, Mingyang Wu, Alex Adronov","doi":"10.1021/acsami.5c18017","DOIUrl":"https://doi.org/10.1021/acsami.5c18017","url":null,"abstract":"Buckypaper (BP), a self-supporting conductive thin film made from carbon nanotubes, is known for its ease of manufacture, excellent repeatability, and promising potential in the electronics field. However, challenges remain in balancing its mechanical strength and conductivity. In this study, we present a simple and effective one-pot synthesis method to fabricate highly conductive and mechanically robust BPs composed of a conjugated polymer (<b>P1</b>)–single-walled carbon nanotube (SWNT) complex and microcrystalline cellulose (MCC). <b>P1</b>, which features a self-immolative linker (SIL) between the polymer backbone and side chain, is used to disperse SWNTs in organic solvents. Upon treatment with tetra-<i>n</i>-butylammonium fluoride (TBAF), the insulating side chains of the polymer are removed to yield <b>P0</b>, which significantly enhances the conductivity of the resulting BP. However, this side chain removal weakens the mechanical strength of the BP. To address this trade-off, MCC was introduced as a mechanical reinforcing agent. Leveraging the good solubility of MCC in a TBAF/DMSO mixture, we developed a one-pot synthesis method to fabricate composite BPs with <b>P0–SWNT</b> complexes and MCC, using TBAF for both solubilization and side chain removal. The composite BPs exhibited improved mechanical properties and conductivity. Notably, a BP containing 42% <b>P0–SWNT</b> by weight demonstrated an optimal balance of strength (tensile modulus of 161 ± 10 MPa, yield point of 11 ± 2%) and conductivity (107 ± 4 S/m). This straightforward and scalable preparation method allows production of BPs with balanced mechanical and electrical properties that may be valuable for downstream applications.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"6 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145718222","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}
Anu Rani,Rishi Sharma,Vikrantvir Jain,Anunay James Pulukuri,Ritama Ghosh,Zhi Zhang,Anjali Sharma
Dendrimers hold immense promises for biomedical applications due to their precisely defined architecture, monodispersity, multivalent surface, and nanoscale dimensions. However, their clinical translation remains constrained by synthetic complexity and purity concerns. Copper-catalyzed Click Chemistry has shown immense potential to construct highly functionalized dendrimers but faces limitations in biological applications due to copper contamination. While metal-free click reactions such as strain-promoted azide-alkyne cycloaddition (SPAAC), thiol-ene coupling, and inverse electron-demand Diels-Alder (IEDDA) have emerged as biocompatible alternatives, their application to the construction of densely functionalized dendrimers remains rare. Here, we report the first integrated metal-free click strategy to construct a second-generation dendrimer (Glucose-60-D) bearing 60 peripheral glucose units using a synergistic sequence of thiol-ene, SPAAC, and IEDDA reactions. This triple-click approach enabled the efficient assembly of a dendrimer bearing 240 surface hydroxyl groups with excellent monodispersity and purity, confirmed by structural, spectroscopic, and chromatographic analyses. Biocompatibility studies across five mammalian cell lines demonstrated excellent cytotolerance at high doses, and mechanistic studies revealed GLUT-mediated uptake as the dominant internalization pathway. In vivo fluorescence imaging studies further demonstrated selective colocalization with microglia and neurons at the site of injury in a pediatric mouse model of traumatic brain injury demonstrating the potential of the Glucose-60-D as a targeted drug delivery nanoplatform. Collectively, this work presents the first demonstration of a divergent, orthogonal, and entirely metal-free click-chemistry approach for constructing a complex dendritic nanocarrier with robust translational potential for drug delivery.
{"title":"Exploring the Power of Metal-Free Click Transformations toward the Synthesis of Highly Functionalized Dendrimers for Applications in Drug Delivery.","authors":"Anu Rani,Rishi Sharma,Vikrantvir Jain,Anunay James Pulukuri,Ritama Ghosh,Zhi Zhang,Anjali Sharma","doi":"10.1021/acsami.5c18754","DOIUrl":"https://doi.org/10.1021/acsami.5c18754","url":null,"abstract":"Dendrimers hold immense promises for biomedical applications due to their precisely defined architecture, monodispersity, multivalent surface, and nanoscale dimensions. However, their clinical translation remains constrained by synthetic complexity and purity concerns. Copper-catalyzed Click Chemistry has shown immense potential to construct highly functionalized dendrimers but faces limitations in biological applications due to copper contamination. While metal-free click reactions such as strain-promoted azide-alkyne cycloaddition (SPAAC), thiol-ene coupling, and inverse electron-demand Diels-Alder (IEDDA) have emerged as biocompatible alternatives, their application to the construction of densely functionalized dendrimers remains rare. Here, we report the first integrated metal-free click strategy to construct a second-generation dendrimer (Glucose-60-D) bearing 60 peripheral glucose units using a synergistic sequence of thiol-ene, SPAAC, and IEDDA reactions. This triple-click approach enabled the efficient assembly of a dendrimer bearing 240 surface hydroxyl groups with excellent monodispersity and purity, confirmed by structural, spectroscopic, and chromatographic analyses. Biocompatibility studies across five mammalian cell lines demonstrated excellent cytotolerance at high doses, and mechanistic studies revealed GLUT-mediated uptake as the dominant internalization pathway. In vivo fluorescence imaging studies further demonstrated selective colocalization with microglia and neurons at the site of injury in a pediatric mouse model of traumatic brain injury demonstrating the potential of the Glucose-60-D as a targeted drug delivery nanoplatform. Collectively, this work presents the first demonstration of a divergent, orthogonal, and entirely metal-free click-chemistry approach for constructing a complex dendritic nanocarrier with robust translational potential for drug delivery.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"35 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145711044","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}
Oleksandr Cherniushok, Taras Parashchuk, Remigiusz Osowski, Anilkumar Bohra, Janusz Tobola, Krzysztof T. Wojciechowski
Driven by their ultralow lattice thermal conductivity and the prospect of a cost-effective, environmentally friendly design, argyrodites have emerged as highly promising candidates for thermoelectric energy conversion. While Ag-based argyrodites can exhibit both n- and p-type conductivity, Cu-based analogues are typically dominated by p-type charge carriers. Moreover, despite the crucial role of defect engineering in enhancing thermoelectric performance, there is still limited knowledge of effective doping strategies for these materials. In this work, we investigate aliovalent iodine substitution at the chalcogen sites in Cu-based argyrodites. Two doping scenarios were explored: a charge-balanced series Cu8–xSi(S0.5Se0.5)6–xIx and a charge-nonbalanced series Cu8Si(S0.5Se0.5)6–xIx. In both cases, iodine substitution increases the lattice parameters and promotes the formation of Cu2Se-based precipitates. Rietveld refinement and theoretical calculations confirm that iodine preferentially occupies the Q3 (4a) anion site. In the charge-nonbalanced samples, doping inefficiencies result in the presence of both electron and hole carriers, leading to complex transport behavior. Conversely, in the charge-balanced samples, iodine substitution increases the hole concentration by creating Cu+ vacancies, which also modifies the Seebeck coefficient and enhances the power factor at elevated temperatures. As a result, iodine-doped Cu7.9SiS2.95Se2.95I0.1 achieves a high thermoelectric figure of merit (ZT ≈ 0.9 at 773 K), demonstrating strong potential for midtemperature thermoelectric power generation.
{"title":"Revealing the Dual Role of Iodine Dopant in Cu-Based Argyrodites via Defect Chemistry","authors":"Oleksandr Cherniushok, Taras Parashchuk, Remigiusz Osowski, Anilkumar Bohra, Janusz Tobola, Krzysztof T. Wojciechowski","doi":"10.1021/acsami.5c18438","DOIUrl":"https://doi.org/10.1021/acsami.5c18438","url":null,"abstract":"Driven by their ultralow lattice thermal conductivity and the prospect of a cost-effective, environmentally friendly design, argyrodites have emerged as highly promising candidates for thermoelectric energy conversion. While Ag-based argyrodites can exhibit both <i>n</i>- and <i>p</i>-type conductivity, Cu-based analogues are typically dominated by <i>p</i>-type charge carriers. Moreover, despite the crucial role of defect engineering in enhancing thermoelectric performance, there is still limited knowledge of effective doping strategies for these materials. In this work, we investigate aliovalent iodine substitution at the chalcogen sites in Cu-based argyrodites. Two doping scenarios were explored: a charge-balanced series Cu<sub>8–<i>x</i></sub>Si(S<sub>0.5</sub>Se<sub>0.5</sub>)<sub>6–<i>x</i></sub>I<sub><i>x</i></sub> and a charge-nonbalanced series Cu<sub>8</sub>Si(S<sub>0.5</sub>Se<sub>0.5</sub>)<sub>6–<i>x</i></sub>I<sub><i>x</i></sub>. In both cases, iodine substitution increases the lattice parameters and promotes the formation of Cu<sub>2</sub>Se-based precipitates. Rietveld refinement and theoretical calculations confirm that iodine preferentially occupies the <i>Q</i>3 (4<i>a</i>) anion site. In the charge-nonbalanced samples, doping inefficiencies result in the presence of both electron and hole carriers, leading to complex transport behavior. Conversely, in the charge-balanced samples, iodine substitution increases the hole concentration by creating Cu<sup>+</sup> vacancies, which also modifies the Seebeck coefficient and enhances the power factor at elevated temperatures. As a result, iodine-doped Cu<sub>7.9</sub>SiS<sub>2.95</sub>Se<sub>2.95</sub>I<sub>0.1</sub> achieves a high thermoelectric figure of merit (<i>ZT</i> ≈ 0.9 at 773 K), demonstrating strong potential for midtemperature thermoelectric power generation.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"3 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145703826","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}
Simultaneously achieving a large stroke, high payload capacity, and structural programmability in coiled polymer muscles remains challenging due to intrinsic structural and fabrication constraints. Here, we present a multilevel helical fabrication scheme that enables stable, large initial coil pitches and programmable helical hierarchies and chirality within a single polymer fiber, effectively bridging the stroke–payload trade-off and greatly expanding the design space for polymer artificial muscles. Second-order muscles demonstrate superior actuation performance: homochiral muscles achieve a contractile stroke of 88.1% and exhibit a 9-fold increase in payload over first-order muscles at 50% contraction (3.6 vs 0.4 MPa), while heterochiral muscles reach an elongation stroke of 860.7%. Third-order muscles transcend the traditional binary homochiral–heterochiral classification, enabling four chirality combinations with unique actuation modes. A regionally controlled twist-fabrication method allows spatial encoding of the hierarchy and chirality within a single fiber, enabling multifunctional and localized actuation. This programmability is demonstrated in soft and biomimetic robots: a robotic arm driven by a single muscle encoding both flexor and extensor functions, a worm-like robot actuated by regionally inverted chirality within one muscle, and a biomimetic finger combining mixed helical levels to achieve faster and more adaptable wrapping motions.
由于固有的结构和制造限制，在卷曲聚合物肌肉中同时实现大冲程、高载荷能力和结构可编程性仍然是一个挑战。在这里，我们提出了一种多层螺旋制造方案，可以在单个聚合物纤维中实现稳定，大的初始线圈螺距和可编程的螺旋层次和手性，有效地弥补了冲程-有效载荷的权衡，极大地扩展了聚合物人造肌肉的设计空间。二阶肌肉表现出优越的驱动性能：同手性肌肉达到88.1%的收缩行程，在50%收缩（3.6 MPa vs 0.4 MPa）时，有效载荷比一阶肌肉增加9倍，而异手性肌肉达到860.7%的延伸行程。三阶肌肉超越了传统的双手性-异手性分类，实现了具有独特驱动模式的四种手性组合。一种区域控制的扭曲制造方法允许在单个纤维内对层次和手性进行空间编码，从而实现多功能和局部驱动。这种可编程性在软机器人和仿生机器人中得到了证明：由编码屈肌和伸肌功能的单个肌肉驱动的机械臂，由一块肌肉内的区域倒手性驱动的蠕虫状机器人，以及结合混合螺旋水平的仿生手指，以实现更快、更适应性的包裹运动。
{"title":"Programmable Helical Hierarchy in Coiled Polymer Artificial Muscles","authors":"Boyi Xu, Feihu Song, Jiaqiao Liang, Yuanwu Feng, Ziyao Zhang, Pengyu Wang, Xiaojie Wang, Yitong Zhou","doi":"10.1021/acsami.5c19885","DOIUrl":"https://doi.org/10.1021/acsami.5c19885","url":null,"abstract":"Simultaneously achieving a large stroke, high payload capacity, and structural programmability in coiled polymer muscles remains challenging due to intrinsic structural and fabrication constraints. Here, we present a multilevel helical fabrication scheme that enables stable, large initial coil pitches and programmable helical hierarchies and chirality within a single polymer fiber, effectively bridging the stroke–payload trade-off and greatly expanding the design space for polymer artificial muscles. Second-order muscles demonstrate superior actuation performance: homochiral muscles achieve a contractile stroke of 88.1% and exhibit a 9-fold increase in payload over first-order muscles at 50% contraction (3.6 vs 0.4 MPa), while heterochiral muscles reach an elongation stroke of 860.7%. Third-order muscles transcend the traditional binary homochiral–heterochiral classification, enabling four chirality combinations with unique actuation modes. A regionally controlled twist-fabrication method allows spatial encoding of the hierarchy and chirality within a single fiber, enabling multifunctional and localized actuation. This programmability is demonstrated in soft and biomimetic robots: a robotic arm driven by a single muscle encoding both flexor and extensor functions, a worm-like robot actuated by regionally inverted chirality within one muscle, and a biomimetic finger combining mixed helical levels to achieve faster and more adaptable wrapping motions.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"211 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145703908","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}
Hydrogel coatings combining superhydrophilicity with ultralow friction on irregular, load-bearing biomedical surfaces are critical yet elusive. Natural mucus, with its highly glycosylated mucin network, protects complex biological surfaces from friction and wear through a uniquely structured lubrication mechanism. Here, inspired by mucin, we engineer hydrogel coatings that are easy to fabricate on diverse substrates, bear high loads, and maintain enduring superlubricity via pure structural design. We introduce a hydration-entropy lubrication coupling strategy in which long, free polymer chains synthesized in situ on the surface maintain a robust hydration layer and high configurational freedom, thereby generating strong shear-induced steric repulsion. By tuning polymerization kinetics in an oxygen-rich environment, we rapidly (≤90 s) form coatings exhibiting ultralow friction (μ = 0.008, 1/20 that of regular hydrogels) and superhydrophilicity (static contact angle = 7.9°). A densely entangled internal network preserves coating integrity and stress transfer, sustaining lubrication at a pressure of ∼0.25 MPa for over 60 days. Incorporation of degradable cross-linkers endows excellent biocompatibility and controllable degradability, fulfilling sustainability requirements for implantable systems. This strategy provides a versatile and facile approach for integrating robust superlubricity hydrogel coatings into complex biological interfaces.
{"title":"A Hydration-Entropy Lubrication Coupling Strategy for Superhydrophilicity and Ultralow Friction of Hydrogel Coatings","authors":"Siming Li, Xiaohui Song, Yuchen Lu, Zilong Han, Shaoxing Qu","doi":"10.1021/acsami.5c21090","DOIUrl":"https://doi.org/10.1021/acsami.5c21090","url":null,"abstract":"Hydrogel coatings combining superhydrophilicity with ultralow friction on irregular, load-bearing biomedical surfaces are critical yet elusive. Natural mucus, with its highly glycosylated mucin network, protects complex biological surfaces from friction and wear through a uniquely structured lubrication mechanism. Here, inspired by mucin, we engineer hydrogel coatings that are easy to fabricate on diverse substrates, bear high loads, and maintain enduring superlubricity via pure structural design. We introduce a hydration-entropy lubrication coupling strategy in which long, free polymer chains synthesized in situ on the surface maintain a robust hydration layer and high configurational freedom, thereby generating strong shear-induced steric repulsion. By tuning polymerization kinetics in an oxygen-rich environment, we rapidly (≤90 s) form coatings exhibiting ultralow friction (<i>μ</i> = 0.008, 1/20 that of regular hydrogels) and superhydrophilicity (static contact angle = 7.9°). A densely entangled internal network preserves coating integrity and stress transfer, sustaining lubrication at a pressure of ∼0.25 MPa for over 60 days. Incorporation of degradable cross-linkers endows excellent biocompatibility and controllable degradability, fulfilling sustainability requirements for implantable systems. This strategy provides a versatile and facile approach for integrating robust superlubricity hydrogel coatings into complex biological interfaces.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"7 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145711506","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}
Floating-gate memories based on two-dimensional (2D) materials show great potential for mimicking synapses in artificial neural networks (ANNs), offering a promising pathway toward hardware neuromorphic computing. However, current implementations predominantly rely on electrical modulation, limiting their applications in future artificial visual systems. Here, we demonstrate an electrooptic dual-mode artificial synapse based on a van der Waals heterostructured MoS2 floating-gate transistor. This device uniquely combines electrically controlled nonvolatile programmability with light-tunable multilevel storage states, enabling versatile synaptic functionalities. Specifically, electrical stimulation induces key synaptic behaviors, including excitatory/inhibitory responses and long-term potentiation/depression, while optical excitation facilitates long-term neuroplasticity through persistent multilevel conductance states. It can also work as an optoelectronic heterosynaptic transistor and perform dual-mode modulation through both electrical and optical inputs. With this characteristic, we demonstrate its application in an ANN visual sensor, which achieves a remarkable recognition accuracy of 91.97% in handwritten digit classification.
{"title":"Electrooptic Dual-Mode Synergetic Control of Two-Dimensional Nonvolatile Floating-Gate Transistors for Artificial Synapses","authors":"Wennan Hu, Zheng Zhang, Haoran Sun, Yuehao Zhao, Yaping He, Zhe Sheng, Zengxing Zhang","doi":"10.1021/acsami.5c17888","DOIUrl":"https://doi.org/10.1021/acsami.5c17888","url":null,"abstract":"Floating-gate memories based on two-dimensional (2D) materials show great potential for mimicking synapses in artificial neural networks (ANNs), offering a promising pathway toward hardware neuromorphic computing. However, current implementations predominantly rely on electrical modulation, limiting their applications in future artificial visual systems. Here, we demonstrate an electrooptic dual-mode artificial synapse based on a van der Waals heterostructured MoS<sub>2</sub> floating-gate transistor. This device uniquely combines electrically controlled nonvolatile programmability with light-tunable multilevel storage states, enabling versatile synaptic functionalities. Specifically, electrical stimulation induces key synaptic behaviors, including excitatory/inhibitory responses and long-term potentiation/depression, while optical excitation facilitates long-term neuroplasticity through persistent multilevel conductance states. It can also work as an optoelectronic heterosynaptic transistor and perform dual-mode modulation through both electrical and optical inputs. With this characteristic, we demonstrate its application in an ANN visual sensor, which achieves a remarkable recognition accuracy of 91.97% in handwritten digit classification.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"34 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145703824","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}
Di Sun, Yujie Xue, Colin Combs, Diane C. Darland, Julia Xiaojun Zhao
Silicon-based nanoparticles (SiNPs), with low toxicity and good biocompatibility, have been investigated for their applications in a wide variety of cell labeling approaches. However, SiNPs are frequently reported to have a strong blue emission and not the more advantageous red-near-infrared (NIR) emission. Porphyrin and its derivatives with red/NIR emission light properties, which can generate reactive singlet oxygen species and have low dark toxicities, have been applied as photosensitizers in therapeutic applications, such as photodynamic therapy (PDT) and photothermal therapy (PTT). However, the inherent limitation of porphyrin is their poor solubility in aqueous solutions. In this work, Tetrakis (4-carboxyphenyl) porphyrin (TCPP) is incorporated with N-(Trimethoxysilylpropyl) Ethylenediamine, triacetic acid, and trisodium salt 35% (TMS-EDTA) to synthesize porphyrin SiNPs (pSiNPs) with red emission that has the added advantage of aqueous solubility. The obtained pSiNPs were characterized by various analytical methods. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to determine the size distribution of the particles (42.7 ± 1.5 nm) and their ζ potentials (−31.6 ± 2.8 mV). Absorption property analysis revealed that the pSiNPs had a wide absorbance range from visible to NIR, with multiple absorbance peaks at 414, 527, 565, and 651 nm. The optical characterization of pSiNPs revealed two distinct emission peaks at 646 and 705 nm. The in vitro cell imaging indicated that pSiNPs were valuable imaging tools for cell labeling and the fluorescent signal from pSiNPs was distributed throughout the cytoplasm and concentrated in the perinuclear region of the cell. The photothermal performance and photodynamic effect showed that the pSiNPs were able to produce laser-induced heat generation that resulted in the formation of reactive oxygen species (ROS), highlighting their potential to achieve PDT and PTT in the cells. The in vitro photosynergistic results indicated that pSiNPs had enhanced PDT/PTT therapeutic performance in the various cancer cell lines tested, including RAW 264.7 cells, MCF-7 cells, and MDA-MB-231 cells.
{"title":"Hydrothermally Synthesized Red-Emissive Porphyrin Silicon Nanoparticles (pSiNPs) for Photo-Induced Synergistic Therapy on Cancer Cells","authors":"Di Sun, Yujie Xue, Colin Combs, Diane C. Darland, Julia Xiaojun Zhao","doi":"10.1021/acsami.5c18462","DOIUrl":"https://doi.org/10.1021/acsami.5c18462","url":null,"abstract":"Silicon-based nanoparticles (SiNPs), with low toxicity and good biocompatibility, have been investigated for their applications in a wide variety of cell labeling approaches. However, SiNPs are frequently reported to have a strong blue emission and not the more advantageous red-near-infrared (NIR) emission. Porphyrin and its derivatives with red/NIR emission light properties, which can generate reactive singlet oxygen species and have low dark toxicities, have been applied as photosensitizers in therapeutic applications, such as photodynamic therapy (PDT) and photothermal therapy (PTT). However, the inherent limitation of porphyrin is their poor solubility in aqueous solutions. In this work, Tetrakis (4-carboxyphenyl) porphyrin (TCPP) is incorporated with N-(Trimethoxysilylpropyl) Ethylenediamine, triacetic acid, and trisodium salt 35% (TMS-EDTA) to synthesize porphyrin SiNPs (pSiNPs) with red emission that has the added advantage of aqueous solubility. The obtained pSiNPs were characterized by various analytical methods. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to determine the size distribution of the particles (42.7 ± 1.5 nm) and their ζ potentials (−31.6 ± 2.8 mV). Absorption property analysis revealed that the pSiNPs had a wide absorbance range from visible to NIR, with multiple absorbance peaks at 414, 527, 565, and 651 nm. The optical characterization of pSiNPs revealed two distinct emission peaks at 646 and 705 nm. The <i>in vitro</i> cell imaging indicated that pSiNPs were valuable imaging tools for cell labeling and the fluorescent signal from pSiNPs was distributed throughout the cytoplasm and concentrated in the perinuclear region of the cell. The photothermal performance and photodynamic effect showed that the pSiNPs were able to produce laser-induced heat generation that resulted in the formation of reactive oxygen species (ROS), highlighting their potential to achieve PDT and PTT in the cells. The <i>in vitro</i> photosynergistic results indicated that pSiNPs had enhanced PDT/PTT therapeutic performance in the various cancer cell lines tested, including RAW 264.7 cells, MCF-7 cells, and MDA-MB-231 cells.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":"3 1","pages":""},"PeriodicalIF":9.5,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145703827","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}
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