Pub Date : 2024-11-13DOI: 10.1016/j.ensm.2024.103904
Yanxia Yu, Ping Li, Xuanyu Xie, Jinhao Xie, Hao Liu, Tzu-Hao Lu, Fan Yang, Xihong Lu, Zujin Yang
Tin (Sn) is an appealing metal anode for aqueous batteries (ABs) due to its high theoretic capacity, elevated hydrogen overpotential, affordability and environmentally friendly nature. However, the parasitic reaction and dead Sn formation are two critical issues that impede the practical application of Sn metal batteries. Herein, we demonstrate that the addition of trace amount of polyvinylpyrrolidone (PVP, 1 mM) into the pristine electrolyte can effectively solve these issues. Specifically, the PVP additive can reshape the structure of Sn2+ solvation sheath to accelerate cations migration and suppress water-induced side reaction and the formation of hydroxide sulfate. Additionally, the preferential adsorption of PVP at the interface also promotes the three-dimensional (3D) diffusion of Sn2+, facilitating uniform Sn deposition. As a result, symmetric cells with PVP additive in the electrolyte deliver stable cycling for up to 1800 h at 10 mA cm−2/1 mAh cm−2 or 230 h at 5 mA cm−2/10 mAh cm−2. The designed electrolyte also enables the MnO2//Sn full battery to maintain a discharge capacity of 0.92 mAh cm−2 over 3000 cycles at current density of 6 mA cm−2 and supports the stable cycling of PbO2//Sn full battery for 230 cycles under the high capacity of 10 mAh cm−2.
锡（Sn）具有理论容量高、氢过电位高、价格低廉和环保等优点，是水电池（ABs）的理想金属阳极。然而，寄生反应和死锡的形成是阻碍锡金属电池实际应用的两个关键问题。在此，我们证明了在原始电解液中添加微量聚乙烯吡咯烷酮（PVP，1 mM）可有效解决这些问题。具体来说，聚乙烯吡咯烷酮添加剂可以重塑 Sn2+ 溶解鞘的结构，加速阳离子迁移，抑制水引起的副反应和硫酸氢氧根的形成。此外，PVP 在界面上的优先吸附作用还能促进 Sn2+ 的三维（3D）扩散，从而促进 Sn 的均匀沉积。因此，在电解液中添加 PVP 的对称电池在 10 mA cm-2/1 mAh cm-2 的条件下可稳定循环 1800 小时，在 5 mA cm-2/10 mAh cm-2 的条件下可稳定循环 230 小时。所设计的电解液还能使 MnO2//Sn 全电池在电流密度为 6 mA cm-2 的条件下，在 3000 次循环中保持 0.92 mAh cm-2 的放电容量，并支持 PbO2//Sn 全电池在 10 mAh cm-2 的高容量条件下稳定循环 230 次。
{"title":"High Areal Capacity and Long-life Sn Anode Enabled by Tuning Electrolyte Solvation Chemistry and Interfacial Adsorbed Molecular Layer","authors":"Yanxia Yu, Ping Li, Xuanyu Xie, Jinhao Xie, Hao Liu, Tzu-Hao Lu, Fan Yang, Xihong Lu, Zujin Yang","doi":"10.1016/j.ensm.2024.103904","DOIUrl":"https://doi.org/10.1016/j.ensm.2024.103904","url":null,"abstract":"Tin (Sn) is an appealing metal anode for aqueous batteries (ABs) due to its high theoretic capacity, elevated hydrogen overpotential, affordability and environmentally friendly nature. However, the parasitic reaction and dead Sn formation are two critical issues that impede the practical application of Sn metal batteries. Herein, we demonstrate that the addition of trace amount of polyvinylpyrrolidone (PVP, 1 mM) into the pristine electrolyte can effectively solve these issues. Specifically, the PVP additive can reshape the structure of Sn<sup>2+</sup> solvation sheath to accelerate cations migration and suppress water-induced side reaction and the formation of hydroxide sulfate. Additionally, the preferential adsorption of PVP at the interface also promotes the three-dimensional (3D) diffusion of Sn<sup>2+</sup>, facilitating uniform Sn deposition. As a result, symmetric cells with PVP additive in the electrolyte deliver stable cycling for up to 1800 h at 10 mA cm<sup>−2</sup>/1 mAh cm<sup>−2</sup> or 230 h at 5 mA cm<sup>−2</sup>/10 mAh cm<sup>−2</sup>. The designed electrolyte also enables the MnO<sub>2</sub>//Sn full battery to maintain a discharge capacity of 0.92 mAh cm<sup>−2</sup> over 3000 cycles at current density of 6 mA cm<sup>−2</sup> and supports the stable cycling of PbO<sub>2</sub>//Sn full battery for 230 cycles under the high capacity of 10 mAh cm<sup>−2</sup>.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"23 1","pages":""},"PeriodicalIF":20.4,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ke Kong, Hong Zhong, Fushuai Zhang, Haowei Lv, Xiaoju Li, Ruihu Wang
Photocatalytic CO2 reduction together with hydrogen generation is a promising approach to generate syngas, the photogenerated electron migration from photosensitizers to the catalytic active sites is the rate-determining step. Herein, an integrative strategy is presented by covalently grafting metal complexes into donor–acceptor covalent triazine-based frameworks. The catalytic active sites are integrated with the photosensitizer units by covalent linkages to form an extended π-conjugated framework, which significantly reduces the energy barrier for the migration of the photogenerated charge carriers, resulting in high activity and durability in photocatalytic CO2 reduction into syngas under visible light irradiation. The CO and H2 evolution amounts in 1.5 h are 1086 and 1042 µmol g−1, respectively, which greatly surpass those in the host-guest counterparts. Furthermore, selective adsorption for CO2 over N2 renders this photocatalytic system to be effective for syngas production from the simulated flue gas. This study provides new approaches to construct the integrative photocatalytic systems for solar-to-chemical energy conversion.
{"title":"The Reduced Barrier for the Photogenerated Charge Migration on Covalent Triazine-Based Frameworks for Boosting Photocatalytic CO2 Reduction Into Syngas","authors":"Ke Kong, Hong Zhong, Fushuai Zhang, Haowei Lv, Xiaoju Li, Ruihu Wang","doi":"10.1002/adfm.202417109","DOIUrl":"https://doi.org/10.1002/adfm.202417109","url":null,"abstract":"Photocatalytic CO<sub>2</sub> reduction together with hydrogen generation is a promising approach to generate syngas, the photogenerated electron migration from photosensitizers to the catalytic active sites is the rate-determining step. Herein, an integrative strategy is presented by covalently grafting metal complexes into donor–acceptor covalent triazine-based frameworks. The catalytic active sites are integrated with the photosensitizer units by covalent linkages to form an extended <i>π</i>-conjugated framework, which significantly reduces the energy barrier for the migration of the photogenerated charge carriers, resulting in high activity and durability in photocatalytic CO<sub>2</sub> reduction into syngas under visible light irradiation. The CO and H<sub>2</sub> evolution amounts in 1.5 h are 1086 and 1042 µmol g<sup>−1</sup>, respectively, which greatly surpass those in the host-guest counterparts. Furthermore, selective adsorption for CO<sub>2</sub> over N<sub>2</sub> renders this photocatalytic system to be effective for syngas production from the simulated flue gas. This study provides new approaches to construct the integrative photocatalytic systems for solar-to-chemical energy conversion.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"95 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qianchen Liu, Tao Wei, Yonghui Zheng, Chuantao Xuan, Lihao Sun, Jing Hu, Miao Cheng, Qianqian Liu, Ruirui Wang, Wanfei Li, Yan Cheng, Bo Liu
Phase-change random access memory is anticipated to break the bottleneck of the “storage wall” due to its advantages in simultaneous data storage and in-memory computing. However, operation speed constrains its application scenarios. Antimony (Sb) thin film has ultrafast phase change speeds, low power consumption, and a straightforward chemical composition. In this study, silicon (Si) doping is employed to enhance the stability of pure Sb while achieving both ultrafast operational speeds and superior thermal stability concurrently. By utilizing optoelectronic hybrid phase change memory, the SET and RESET operation speeds can reach as fast as 26 and 13 ps, respectively, when using Si-doped Sb films. The absence of the Si─Sb bond results in simple cubic nuclei within the amorphous film, which is posited as the structural basis for the high operational speed. These novel insights into ultrafast speed and phase mechanisms are poised to have valuable evidence for future high-speed memory designs.
{"title":"Picosecond Operation of Optoelectronic Hybrid Phase Change Memory Based on Si-Doped Sb Films","authors":"Qianchen Liu, Tao Wei, Yonghui Zheng, Chuantao Xuan, Lihao Sun, Jing Hu, Miao Cheng, Qianqian Liu, Ruirui Wang, Wanfei Li, Yan Cheng, Bo Liu","doi":"10.1002/adfm.202417128","DOIUrl":"https://doi.org/10.1002/adfm.202417128","url":null,"abstract":"Phase-change random access memory is anticipated to break the bottleneck of the “storage wall” due to its advantages in simultaneous data storage and in-memory computing. However, operation speed constrains its application scenarios. Antimony (Sb) thin film has ultrafast phase change speeds, low power consumption, and a straightforward chemical composition. In this study, silicon (Si) doping is employed to enhance the stability of pure Sb while achieving both ultrafast operational speeds and superior thermal stability concurrently. By utilizing optoelectronic hybrid phase change memory, the SET and RESET operation speeds can reach as fast as 26 and 13 ps, respectively, when using Si-doped Sb films. The absence of the Si─Sb bond results in simple cubic nuclei within the amorphous film, which is posited as the structural basis for the high operational speed. These novel insights into ultrafast speed and phase mechanisms are poised to have valuable evidence for future high-speed memory designs.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"6 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wenxuan Peng, Jiamin Zhao, Qiuxian Li, Yue Sun, Guoli Du, Fangyuan Tang, Yongfei Liu, Qingdi Hu, Xusheng Li, Shuangxi Nie
Ion-gels, with inherent flexibility, tunable conductivity, and multi-stimulus response, have attracted significant attention in flexible/wearable electronics. However, the design of ion-gels that exhibit both strength and toughness is challenging. In this study, a novel ion-gel design is proposed that mimics the hierarchical meshing structure of leaves in combination with ion hybridization. Polyacrylamide (PAM) is incorporated in TEMPO oxidized cellulose nanofibers (TOCNFs) clusters by in situ polymerization, generating a hydrogel with micro/nanoscale entangled networks. Replacement of water by a metal halide ionic liquid ([BMIm]ZnxCly) in the hydrogel resulted in the formation of an ion hybrid network with supramolecular interactions. The integration of the PAM/TOCNF polymer network with [BMIm]ZnxCly resulted in ion-gels with high strength (5.9 MPa), toughness (22 MJ m−3), and enhanced elastic modulus (30 MPa) combined with non-flammability, heat and cold resistance. While having fast responsiveness (36 ms) of sensing signal and stability of power supply even at 4000 cycle collisions. Stable signal output even at high (200 °C) /sub-zero temperatures. The proposed strategy offers a new approach to the material design of flexible/wearable electronics.
{"title":"A Strong and Tough Ion-gel Enabled by Hierarchical Meshing and Ion Hybridizations Collaboration","authors":"Wenxuan Peng, Jiamin Zhao, Qiuxian Li, Yue Sun, Guoli Du, Fangyuan Tang, Yongfei Liu, Qingdi Hu, Xusheng Li, Shuangxi Nie","doi":"10.1002/adfm.202414682","DOIUrl":"https://doi.org/10.1002/adfm.202414682","url":null,"abstract":"Ion-gels, with inherent flexibility, tunable conductivity, and multi-stimulus response, have attracted significant attention in flexible/wearable electronics. However, the design of ion-gels that exhibit both strength and toughness is challenging. In this study, a novel ion-gel design is proposed that mimics the hierarchical meshing structure of leaves in combination with ion hybridization. Polyacrylamide (PAM) is incorporated in TEMPO oxidized cellulose nanofibers (TOCNFs) clusters by in situ polymerization, generating a hydrogel with micro/nanoscale entangled networks. Replacement of water by a metal halide ionic liquid ([BMIm]Zn<sub>x</sub>Cl<sub>y</sub>) in the hydrogel resulted in the formation of an ion hybrid network with supramolecular interactions. The integration of the PAM/TOCNF polymer network with [BMIm]Zn<sub>x</sub>Cl<sub>y</sub> resulted in ion-gels with high strength (5.9 MPa), toughness (22 MJ m<sup>−3</sup>), and enhanced elastic modulus (30 MPa) combined with non-flammability, heat and cold resistance. While having fast responsiveness (36 ms) of sensing signal and stability of power supply even at 4000 cycle collisions. Stable signal output even at high (200 °C) /sub-zero temperatures. The proposed strategy offers a new approach to the material design of flexible/wearable electronics.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"20 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wenting Shi, Xi Ying, Xinyi Sheng, Soumen Das, Dongjing He, Kasie Collins, Yuhang Hu, M.G. Finn
Injectable hydrogels represent a promising strategy for the extended release of biological molecules, thereby reducing the frequency of injections. This study introduces a novel system based on Michael addition of dextran and polyethylene glycol (PEG) polymers functionalized with oxanorbornadiene (OND) and thiol groups, respectively. Reliable control over gelation speed allows administration by injection using a simple syringe-to-syringe mixing protocol that entrains more than 95% of virus-like particle (VLP) cargo. A combination of retro-Diels-Alder and hydrolytic ester bond cleavage gives rise to programmable release of the VLPs. Different release profiles, including burst, linear, and delayed release over a two-week period, are engineered using different OND linkages, and rheological characterization shows the hydrogels to be well within the desired range of stiffness for subcutaneous use. The modular nature of this system offers a generalizable platform for developing degradable materials aimed at sustained release biomedical applications.
{"title":"Injectable Hydrogels for Programmable Nanoparticle Release","authors":"Wenting Shi, Xi Ying, Xinyi Sheng, Soumen Das, Dongjing He, Kasie Collins, Yuhang Hu, M.G. Finn","doi":"10.1002/adfm.202409796","DOIUrl":"https://doi.org/10.1002/adfm.202409796","url":null,"abstract":"Injectable hydrogels represent a promising strategy for the extended release of biological molecules, thereby reducing the frequency of injections. This study introduces a novel system based on Michael addition of dextran and polyethylene glycol (PEG) polymers functionalized with oxanorbornadiene (OND) and thiol groups, respectively. Reliable control over gelation speed allows administration by injection using a simple syringe-to-syringe mixing protocol that entrains more than 95% of virus-like particle (VLP) cargo. A combination of retro-Diels-Alder and hydrolytic ester bond cleavage gives rise to programmable release of the VLPs. Different release profiles, including burst, linear, and delayed release over a two-week period, are engineered using different OND linkages, and rheological characterization shows the hydrogels to be well within the desired range of stiffness for subcutaneous use. The modular nature of this system offers a generalizable platform for developing degradable materials aimed at sustained release biomedical applications.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"38 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Energy-efficient yet energy-dense soft actuators are essential for untethered wearable robots. This work reports a fabric-like actuator, combining shape memory alloy (SMA) springs and electrostatic clutches (ESClutches). The SMA springs provide high force density, with only 18 g of materials generating 40 N of force at actuation strains of over 35%, but requiring 78 W of power to hold that strain. The ESClutches cannot generate motion on their own, but can maintain the force and contraction generated by SMAs consuming only a few mW, thus allowing the SMAs to be turned off. By combining SMAs and ESClutches, a soft wearable fabric actuator is developed with force and stroke suited for an upper-limb soft exoskeleton, able to lock in any given position using negligible power. The design is scalable: the number and dimensions of the SMA springs and of the ESClutches can be chosen to meet size and actuator performance requirements. This work reports two wearable use cases, where the combined SMAs and ESClutches consume over 70% lower power than SMAs alone.
高能效、高能量密度的软致动器对于无系绳可穿戴机器人至关重要。这项研究报告了一种类似织物的致动器，它结合了形状记忆合金（SMA）弹簧和静电离合器（ESClutches）。SMA 弹簧具有很高的力密度，只需 18 克材料就能产生 40 牛顿的力，致动应变超过 35%，但保持该应变需要 78 瓦的功率。ESClutches 本身不能产生运动，但可以维持 SMA 产生的力和收缩，耗电量仅为几毫瓦，因此可以关闭 SMA。通过将 SMA 与 ESClutches 相结合，我们开发出了一种可穿戴软织物致动器，其力和行程适合上肢软外骨骼，能够以可忽略不计的功率锁定在任何给定位置。该设计具有可扩展性：可选择 SMA 弹簧和 ESClutches 的数量和尺寸，以满足尺寸和致动器性能要求。这项工作报告了两个可穿戴使用案例，其中 SMA 和 ESClutches 组合的功耗比单独使用 SMA 低 70% 以上。
{"title":"Clutchable Fabric Actuator for Energy-Efficient Wearable Robots","authors":"Huapeng Zhang, Herbert Shea","doi":"10.1002/adfm.202415099","DOIUrl":"https://doi.org/10.1002/adfm.202415099","url":null,"abstract":"Energy-efficient yet energy-dense soft actuators are essential for untethered wearable robots. This work reports a fabric-like actuator, combining shape memory alloy (SMA) springs and electrostatic clutches (ESClutches). The SMA springs provide high force density, with only 18 g of materials generating 40 N of force at actuation strains of over 35%, but requiring 78 W of power to hold that strain. The ESClutches cannot generate motion on their own, but can maintain the force and contraction generated by SMAs consuming only a few mW, thus allowing the SMAs to be turned off. By combining SMAs and ESClutches, a soft wearable fabric actuator is developed with force and stroke suited for an upper-limb soft exoskeleton, able to lock in any given position using negligible power. The design is scalable: the number and dimensions of the SMA springs and of the ESClutches can be chosen to meet size and actuator performance requirements. This work reports two wearable use cases, where the combined SMAs and ESClutches consume over 70% lower power than SMAs alone.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"158 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guangliang Li, Hu Long, Sally Turner, Amin Azizi, Aiming Yan, Zhen Yuan, Guanglan Liao, Carlo Carraro, Roya Maboudian, Tielin Shi, Alex Zettl
Recently, hexagonal boron nitride (h-BN) nanomaterials, e.g., nanosheets and nanotubes, have been predicted to be effective materials for reversible gas adsorption with high selectivity once charged. However, despite the encouraging theoretical predictions, sensing with h-BN is difficult to realize experimentally due to its electrically insulating nature stemming from its large band gap. In this research, the controlled synthesis of high surface area hybrid h-BN/graphene aerogel is reported, using high-quality graphene as a template, and its application for selective gas sensing. It is discovered for the first time in this system that the difficulty of conversion in template synthesis of h-BN is positively correlated with the quality of the carbon template, an observation that is verified on both graphene nanosheets and carbon nanotubes. The application of this hybrid material for gas sensing yields ppb level of detection limit and high selectivity for NH3. Through density functional theory calculations, the adsorption energy and charge transfer between NH3 molecules and aerogel are greatly enhanced. Therefore, this innovative approach promises new possibilities for the application of h-BN in gas sensing, with the potential to play a significant role in gas capture, environmental monitoring, and other related fields.
{"title":"Template Quality Dependent Conversion Synthesis of Boron Nitride Coated Graphene Hybrid Aerogels for Ultrasensitive and Selective Ammonia Sensing","authors":"Guangliang Li, Hu Long, Sally Turner, Amin Azizi, Aiming Yan, Zhen Yuan, Guanglan Liao, Carlo Carraro, Roya Maboudian, Tielin Shi, Alex Zettl","doi":"10.1002/adfm.202416251","DOIUrl":"https://doi.org/10.1002/adfm.202416251","url":null,"abstract":"Recently, hexagonal boron nitride (h-BN) nanomaterials, e.g., nanosheets and nanotubes, have been predicted to be effective materials for reversible gas adsorption with high selectivity once charged. However, despite the encouraging theoretical predictions, sensing with h-BN is difficult to realize experimentally due to its electrically insulating nature stemming from its large band gap. In this research, the controlled synthesis of high surface area hybrid h-BN/graphene aerogel is reported, using high-quality graphene as a template, and its application for selective gas sensing. It is discovered for the first time in this system that the difficulty of conversion in template synthesis of h-BN is positively correlated with the quality of the carbon template, an observation that is verified on both graphene nanosheets and carbon nanotubes. The application of this hybrid material for gas sensing yields ppb level of detection limit and high selectivity for NH<sub>3</sub>. Through density functional theory calculations, the adsorption energy and charge transfer between NH<sub>3</sub> molecules and aerogel are greatly enhanced. Therefore, this innovative approach promises new possibilities for the application of h-BN in gas sensing, with the potential to play a significant role in gas capture, environmental monitoring, and other related fields.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"40 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soundarya Nagarajan, Ingmar Ratschinski, Stefan Schmult, Steffen Wirth, Dirk König, Thomas Mikolajick, Daniel Hiller, Jens Trommer
Impurity doping at the nanoscale for silicon is becoming less efficient with conventional techniques. Here, an alternative virtual doping method is presented for silicon that can achieve an equivalent carrier density while addressing the primary limitations of traditional doping methods. The doping for silicon is carried out by placing aluminum-induced acceptor states externally in a silicon dioxide dielectric shell. This technique can be referred to as direct modulation doping. The resistivity, carrier density, and mobility are investigated by Hall effect measurements to characterize the carrier transport using the new doping method. The results thereof are compared with carrier transport analysis of conventionally doped silicon at room-temperature, demonstrating a 100% increase in carrier mobility at equal carrier density. The sheet density of hole carriers in silicon due to modulation doping remains nearly constant, ≈4.7 × 1012 cm−2 over a wide temperature range from 300 down to 2 K, proving that modulation-doped devices do not undergo carrier freeze-out at cryogenic temperatures. In addition, a mobility enhancement is demonstrated with an increase from 89 cm2 Vs−1 at 300 K to 227 cm2 Vs−1 at 10 K, highlighting the benefits of the new method for creating emerging nanoscale electronic devices or peripheral cryo-electronics to quantum computing.
采用传统技术在纳米级掺杂硅杂质的效率越来越低。本文介绍了一种替代性的硅虚拟掺杂方法，这种方法可以达到等效的载流子密度，同时解决传统掺杂方法的主要局限性。硅的掺杂是通过在二氧化硅电介质外壳外部放置铝诱导的受体态来实现的。这种技术可称为直接调制掺杂。通过霍尔效应测量研究了电阻率、载流子密度和迁移率，以确定使用新掺杂方法的载流子传输特性。其结果与室温下传统掺杂硅的载流子传输分析进行了比较，结果表明在载流子密度相同的情况下，载流子迁移率提高了 100%。由于调制掺杂，硅中空穴载流子的片密度在 300 至 2 K 的宽温度范围内几乎保持不变，≈4.7 × 1012 cm-2，这证明调制掺杂器件在低温条件下不会出现载流子冻结现象。此外，还证明了迁移率的提高，从 300 K 时的 89 cm2 Vs-1 提高到 10 K 时的 227 cm2 Vs-1，凸显了这种新方法在创建新兴纳米级电子器件或外围低温电子学到量子计算方面的优势。
{"title":"Analyzing Carrier Density and Hall Mobility in Impurity-Free Silicon Virtually Doped by External Defect Placement","authors":"Soundarya Nagarajan, Ingmar Ratschinski, Stefan Schmult, Steffen Wirth, Dirk König, Thomas Mikolajick, Daniel Hiller, Jens Trommer","doi":"10.1002/adfm.202415230","DOIUrl":"https://doi.org/10.1002/adfm.202415230","url":null,"abstract":"Impurity doping at the nanoscale for silicon is becoming less efficient with conventional techniques. Here, an alternative virtual doping method is presented for silicon that can achieve an equivalent carrier density while addressing the primary limitations of traditional doping methods. The doping for silicon is carried out by placing aluminum-induced acceptor states externally in a silicon dioxide dielectric shell. This technique can be referred to as direct modulation doping. The resistivity, carrier density, and mobility are investigated by Hall effect measurements to characterize the carrier transport using the new doping method. The results thereof are compared with carrier transport analysis of conventionally doped silicon at room-temperature, demonstrating a 100% increase in carrier mobility at equal carrier density. The sheet density of hole carriers in silicon due to modulation doping remains nearly constant, ≈4.7 × 10<sup>12</sup> cm<sup>−2</sup> over a wide temperature range from 300 down to 2 K, proving that modulation-doped devices do not undergo carrier freeze-out at cryogenic temperatures. In addition, a mobility enhancement is demonstrated with an increase from 89 cm<sup>2</sup> Vs<sup>−1</sup> at 300 K to 227 cm<sup>2</sup> Vs<sup>−1</sup> at 10 K, highlighting the benefits of the new method for creating emerging nanoscale electronic devices or peripheral cryo-electronics to quantum computing.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"3 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Boron nitride has attracted scientific interest in recent years due to its potential use in electronics, both as hexagonal (hBN) and cubic (cBN) phases. While both are successfully realized through chemical vapor deposition, the heteroepitaxial growth of cBN on another iconic semiconductor, diamond is plagued with mixed-phase formation. Employing first-principles computations and a nanoreactor approach, the BN phase preferences are explored on diamond (001) controlled—as it is discovered—by the hydrogen gas concentration. In a limited-hydrogen environment, the initial BN-island expands along the diamond surface, forming a 3D metastable cubic phase that grows in the direction normal to the basal plane through kinetically-limited nucleation, thus overcoming the thermodynamic preference toward the hBN phase. Comparatively, the amorphous phase is favored in the absence of hydrogen, while the hexagonal phase dominates at its high levels, elucidating numerous experimental observations. A obtained kinetic phase diagram connects the phase with hydrogen chemical potential to facilitate targeted phase selection. The results suggest that gas-mediated nucleation kinetics provide feasible control for the precise synthesis. It also offers valuable guidance for the controllable synthesis of desired BN phases and advances research toward potential BN electronics.
{"title":"Hydrogen-Driven Phase Differentiation in BN Nucleation on Diamond","authors":"Ting Cheng, Ksenia V. Bets, Boris I. Yakobson","doi":"10.1002/adfm.202413675","DOIUrl":"https://doi.org/10.1002/adfm.202413675","url":null,"abstract":"Boron nitride has attracted scientific interest in recent years due to its potential use in electronics, both as hexagonal (hBN) and cubic (cBN) phases. While both are successfully realized through chemical vapor deposition, the heteroepitaxial growth of cBN on another iconic semiconductor, diamond is plagued with mixed-phase formation. Employing first-principles computations and a nanoreactor approach, the BN phase preferences are explored on diamond (001) controlled—as it is discovered—by the hydrogen gas concentration. In a limited-hydrogen environment, the initial BN-island expands along the diamond surface, forming a 3D metastable cubic phase that grows in the direction normal to the basal plane through kinetically-limited nucleation, thus overcoming the thermodynamic preference toward the hBN phase. Comparatively, the amorphous phase is favored in the absence of hydrogen, while the hexagonal phase dominates at its high levels, elucidating numerous experimental observations. A obtained kinetic phase diagram connects the phase with hydrogen chemical potential to facilitate targeted phase selection. The results suggest that gas-mediated nucleation kinetics provide feasible control for the precise synthesis. It also offers valuable guidance for the controllable synthesis of desired BN phases and advances research toward potential BN electronics.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"196 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142599890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Self‐hygroscopic hydrogels, characterized by high evaporation enthalpy, cooling efficiency, and self‐regulating properties, have garnered significant attention. However, most current research focuses on enhancing the hygroscopic and desorption performance, often overlooking the importance of monitoring the self‐regulation process, which limits its further application. Advanced visualization technologies, such as in situ electrical impedance tomography, low‐field nuclear magnetic resonance, and hyperspectral imaging, offer potential insights into this behavior, yet they often require additional devices, incur high costs, and involve complex sample preparation processes. Therefore, drawing inspiration from nature, humidity‐color‐sensitive hydrogels (HCSHs) strategy is proposed for visualized cooling. Benefiting from the strong polar responsiveness of the aggregation‐induced emission (AIE) molecules, the hydrogel's fluorescence significantly changes with varying interior water content, thereby its self‐regulation process is monitored easily. Further, the obtained hydrogel could be applied in the electronic device cooling owing to the polymer skeletons’ high swelling ratio, strong adhesion, and excellent self‐hygroscopic properties. This strategy overcomes current limitations in the visual technology of self‐hygroscopic materials and provides new insights into intelligent thermal management for electronic devices.
{"title":"Bioinspired Passive Cooling Hydrogel for Visualizing Hygroscopicity and Desorption Process","authors":"Yabi Yang, Xiaohe Zhou, Xiaofan Ji, Wanpeng Liu, Qingyun Li, Chuanbiao Zhu, Xiaolong Li, Shuang Liu, Xiang Lu, Jinping Qu","doi":"10.1002/adfm.202416776","DOIUrl":"https://doi.org/10.1002/adfm.202416776","url":null,"abstract":"Self‐hygroscopic hydrogels, characterized by high evaporation enthalpy, cooling efficiency, and self‐regulating properties, have garnered significant attention. However, most current research focuses on enhancing the hygroscopic and desorption performance, often overlooking the importance of monitoring the self‐regulation process, which limits its further application. Advanced visualization technologies, such as in situ electrical impedance tomography, low‐field nuclear magnetic resonance, and hyperspectral imaging, offer potential insights into this behavior, yet they often require additional devices, incur high costs, and involve complex sample preparation processes. Therefore, drawing inspiration from nature, humidity‐color‐sensitive hydrogels (HCSHs) strategy is proposed for visualized cooling. Benefiting from the strong polar responsiveness of the aggregation‐induced emission (AIE) molecules, the hydrogel's fluorescence significantly changes with varying interior water content, thereby its self‐regulation process is monitored easily. Further, the obtained hydrogel could be applied in the electronic device cooling owing to the polymer skeletons’ high swelling ratio, strong adhesion, and excellent self‐hygroscopic properties. This strategy overcomes current limitations in the visual technology of self‐hygroscopic materials and provides new insights into intelligent thermal management for electronic devices.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"37 1","pages":""},"PeriodicalIF":19.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142599071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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