Advanced Materials & Technologies最新文献_第5页

Diffusion of Zirconium (IV) Ions from Coated Thick Zirconium Oxide Shell to the Bulk Structure of Ni‐Rich NMC811 Cathode Leading to High‐Performance 18650 Cylindrical Li‐Ion Batteries 锆(IV)离子从涂层厚氧化锆壳向富镍NMC811正极体结构扩散制备高性能18650圆柱形锂离子电池

Advanced Materials & Technologies Pub Date : 2022-06-30 DOI: 10.1002/admt.202200436

Suchakree Tubtimkuna, Nutthaphon Phattharasupakun, Panyawee Bunyanidhi, Montree Sawangphruk

{"title":"Diffusion of Zirconium (IV) Ions from Coated Thick Zirconium Oxide Shell to the Bulk Structure of Ni‐Rich NMC811 Cathode Leading to High‐Performance 18650 Cylindrical Li‐Ion Batteries","authors":"Suchakree Tubtimkuna, Nutthaphon Phattharasupakun, Panyawee Bunyanidhi, Montree Sawangphruk","doi":"10.1002/admt.202200436","DOIUrl":"https://doi.org/10.1002/admt.202200436","url":null,"abstract":"Herein, Ni‐rich LiNi0.8Mn0.1Co0.1O2 or NMC811 cathode material, which is expected to be widely used soon, is coated by crystalline ZrO2 nanoparticles using green and scalable mechanofusion technique with an annealing process. A controllable synergistic effect of ZrO2 coating, as a spherical core–shell morphology with low surface energy, which is ideal for the process of electrode fabrication, and Zr4+ doping is carefully investigated. For the first time, the mechanofusion with the post‐annealing at 800 °C used in this work can finely tune the shell thickness and doping gradient by the diffusion of Zr4+ from the coated ZrO2 shell to the bulk structure of NMC811. The optimized material, namely NMC@Zr‐800 used as the cathode of 18650 cylindrical Li‐ion batteries (LIBs), can provide excellent capacity retention over 1000 cycles at a severe 100% state‐of‐charge (SOC) at 1.0 C. Postmortem analysis shows that the material is stable with less crack formation and transition metal (TM) dissolution than the pristine NMC811 material owing to a synergistic effect of the surface protection by ZrO2 coating and Zr4+ doping. The results demonstrate the practical and scalable approach that will be beneficial for technological advancement in the high‐energy 18650 cylindrical LIBs.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73874019","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}

引用次数: 4

Mechano‐Sensor for Proprioception Inspired by Ultrasensitive Slit‐Based Mechanosensilla 受超灵敏狭缝机械感受器启发的本体感觉机械传感器

Advanced Materials & Technologies Pub Date : 2022-06-29 DOI: 10.1002/admt.202200424

Kejun Wang, Lei Zhang, Yuecheng Gui, Cheng Fan, Tao Sun, Lining Sun, Qian Wang, Junqiu Zhang, Zhiwu Han

{"title":"Mechano‐Sensor for Proprioception Inspired by Ultrasensitive Slit‐Based Mechanosensilla","authors":"Kejun Wang, Lei Zhang, Yuecheng Gui, Cheng Fan, Tao Sun, Lining Sun, Qian Wang, Junqiu Zhang, Zhiwu Han","doi":"10.1002/admt.202200424","DOIUrl":"https://doi.org/10.1002/admt.202200424","url":null,"abstract":"Internal mechanosensors, as the core component of a proprioceptive system, provide vital mechanical information from intelligent devices for adaptive motor control, mechanical fault diagnosis, and machining condition monitoring. However, developing a sophisticated mechanosensory structure that can be widely used is highly desirable to significantly improve the detection performance of internal mechanosensors. Coincidentally, in nature, optimized microscale slits of arachnids (e.g., scorpions and spiders) are ingeniously used as a mechanosensory structure for internal mechanosensilla to efficiently detect the inevitable internal mechanical feedbacks caused by self‐motion and external mechanical stimuli. Biological slit‐based mechano‐sensilla provide an attractive bio‐inspired strategy to use the controllable slit as the sensory structure to improve the perceptual performance of internal mechanosensors. In this study, the structure‐deformation‐performance coupling relationship of slit‐based mechano‐sensilla is explored through experiment and theoretical analysis. An artificial slit‐based mechanosensor is developed by mimicking the combined deformation properties of the slit and the ultrathin cuticular membrane covering the slit tail. This bio‐inspired mechanosensor shows excellent performance in terms of mechanical stability, response time, and sensitivity to mechanical signals. The research on a practical application highlights the importance of the unique basic “design” principles of the slit‐based mechano‐sensilla in improving the proprioceptive capability of smart engineering devices.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73655479","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}

引用次数: 0

Low Cost and Facile Fabrication of a Micro‐Mold with High Aspect Ratio for Transparent Electrodes with Metal Mesh Using Micro‐Scale 3D Printing 使用微尺度3D打印技术制造具有高纵横比的透明金属网电极微模具的低成本和简易制造

Advanced Materials & Technologies Pub Date : 2022-06-28 DOI: 10.1002/admt.202200584

Luanfa Sun, Rui Wang, Xiaoyan Zhu, Hongke Li, Jinbao Zhang, Fei Wang, Guangming Zhang, Jianjun Yang, Zilong Peng, Yuan-Fang Zhang, Hongbo Lan

{"title":"Low Cost and Facile Fabrication of a Micro‐Mold with High Aspect Ratio for Transparent Electrodes with Metal Mesh Using Micro‐Scale 3D Printing","authors":"Luanfa Sun, Rui Wang, Xiaoyan Zhu, Hongke Li, Jinbao Zhang, Fei Wang, Guangming Zhang, Jianjun Yang, Zilong Peng, Yuan-Fang Zhang, Hongbo Lan","doi":"10.1002/admt.202200584","DOIUrl":"https://doi.org/10.1002/admt.202200584","url":null,"abstract":"Transparent electrodes (TEs) with metal mesh are regarded as a substitute for traditional indium tin oxide (ITO) due to their excellent optoelectronic properties. The manufacture of metal mesh based on micro‐molds will be a low‐cost and high‐efficiency method, but the cost‐effective fabrication of micro‐molds with a high aspect ratio (AR) currently faces challenges. Here, a polymer micro‐mold with high AR based on an electric‐field‐driven (EFD) micro‐scale 3D printing and molding process is proposed for the mass production of TEs with metal meshes. The final fabricated flexible transparent electrode (FTE) based on polymer micro‐mold with high AR exhibits superior optoelectronic properties with a figure of merit (FOM) of 1800, as well as excellent mechanical stability with a slight increase in the sheet resistance (Rs) during cyclic bending, scratching, torsion, and adhesion tests. Furthermore, the fabricated rigid TE based on polymer micro‐mold shows remarkable performance and stability with a FOM of 2500, a negligible increase in the Rs under harsh working conditions, and a robust heating cycle. Whether used for the manufacture of FTEs or rigid TEs, the polymer micro‐mold shows good service life. This strategy provides support for the efficient and environmentally friendly mass production of high‐performance TEs.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83079836","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}

引用次数: 6

High‐Barrier‐Height Ti3C2Tx/Si Microstructure Schottky Junction‐Based Self‐Powered Photodetectors for Photoplethysmographic Monitoring 高势垒高度Ti3C2Tx/Si微结构肖特基结自供电光电探测器，用于光电体积脉搏监测

Advanced Materials & Technologies Pub Date : 2022-06-28 DOI: 10.1002/admt.202200555

Longmei Song, Enze Xu, Yongqiang Yu, Jianyong Jie, Yu Xia, Shirong Chen, Yang Jiang, Gaobin Xu, Dachuang Li, Jiansheng Jie

{"title":"High‐Barrier‐Height Ti3C2Tx/Si Microstructure Schottky Junction‐Based Self‐Powered Photodetectors for Photoplethysmographic Monitoring","authors":"Longmei Song, Enze Xu, Yongqiang Yu, Jianyong Jie, Yu Xia, Shirong Chen, Yang Jiang, Gaobin Xu, Dachuang Li, Jiansheng Jie","doi":"10.1002/admt.202200555","DOIUrl":"https://doi.org/10.1002/admt.202200555","url":null,"abstract":"A high Schottky barrier height (ΦB) is one of the essential prerequisites for achieving high‐performance self‐powered Schottky‐barrier diode (SBD)‐based photodetector. The ΦB value is predominantly determined by the metal function and interface quality of the metal/semiconductor contact. 2D MXenes with adjustable work functions and dangling bond‐free properties are promising building blocks for constructing self‐powered SBD with high ΦB. Herein, a novel Ti3C2Tx MXene/Si hexagonal microhole array (SiHMA) van der Waals SBD is developed for the first time via a feasible solution process. Significantly, the device possesses a large ΦB up to ≈1.07 eV, which is among the highest for the Si‐based SBD. In consequence, the Ti3C2Tx/SiHMA SBD yields a large responsivity up to 302 mA W−1 and detectivity as high as 5.4 × 1013 Jones in a self‐powered model, surpassing the performance of most 2D material/Si photodiodes reported to date. Furthermore, it is demonstrated that featured and reliable fingertip photoplethysmogram (PPG) signals can be detected using the self‐powered SBD, enabling us to further accurately extract the heart rate (HR), and blood pressures (BP) using the PPG‐only method. This work paves the way for the construction of high‐performance MXenes‐based self‐powered SBDs for health monitoring.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73800993","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}

引用次数: 13

A Fully 3D‐Printed Tortoise‐Inspired Soft Robot with Terrains‐Adaptive and Amphibious Landing Capabilities 一个完全3D打印乌龟启发的软机器人，具有地形适应性和两栖登陆能力

Advanced Materials & Technologies Pub Date : 2022-06-26 DOI: 10.1002/admt.202200536

Ming-Kuen Wu, Xiaoxian Xu, Qianchuan Zhao, W. Afridi, Ningzhe Hou, Rahdar Hussain Afridi, Xingwen Zheng, Chen Wang, Guangming Xie

引用次数: 13

Inkjet Printing Efficient Defined‐Pixel Matrix Perovskite Light‐Emitting Diodes with a Polar Polymer Modification Layer 具有极性聚合物修饰层的高效定义像素矩阵钙钛矿发光二极管喷墨打印

Advanced Materials & Technologies Pub Date : 2022-06-25 DOI: 10.1002/admt.202200370

Junjie Wang, Danyang Li, Yunpeng Luo, Jian Wang, Junbiao Peng

{"title":"Inkjet Printing Efficient Defined‐Pixel Matrix Perovskite Light‐Emitting Diodes with a Polar Polymer Modification Layer","authors":"Junjie Wang, Danyang Li, Yunpeng Luo, Jian Wang, Junbiao Peng","doi":"10.1002/admt.202200370","DOIUrl":"https://doi.org/10.1002/admt.202200370","url":null,"abstract":"Perovskite light‐emitting diodes (PeLEDs) for full‐color displays based on inkjet printing technology are increasingly attractive. For potential applications, fabricating high‐quality perovskite films with defined‐pixel sizes is crucially important. The key issue is how to control the contact properties between the perovskite ink and a hole transport layer (HTL). In this study, a novel strategy is proposed by using the poly[(9,9‐bis(3′‐((N,N‐dimethyl)‐N‐ethylammonium)‐propyl)‐2,7‐fluorene)‐alt‐2,7‐(9,9‐dioctylfluorene)] dibromide (PFN‐Br) polar polymer to modify the HTL surface, instead of conventional O2 plasma method. The PFN‐Br can enhance the surface energy of HTLs, including PVK, Poly‐TPD, TFB, etc., and improve the wettability of perovskite inks on the HTL due to its polar quaternary ammonium groups. Besides, the PFN‐Br acts as the easier nucleation to induce a tiny crystallization of perovskites. On the other hand, the diphenyl phosphate liver (DPA) is first used to mix in perovskite inks to optimize the perovskite film phase distribution and the elimination of uncoordinated Pb2+, resulting from interactions between PEA+ and DPA, Pb2+ and DPA, respectively. As a result, a defined‐pixel matrix green quasi‐2D PeLED with the peak external quantum efficiency over 10% via inkjet printing technique is achieved, which is the most efficient matrix green PeLEDs fabricated by inkjet printing technique so far.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"89 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79170941","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}

引用次数: 9

Power Generation on Chips: Harvesting Energy From the Sun and Cold Space 芯片上的发电:从太阳和寒冷空间收集能量

Advanced Materials & Technologies Pub Date : 2022-06-22 DOI: 10.1002/admt.202200478

Shuai Zhang, Zhenhua Wu, Zekun Liu, Erzhen Mu, Yang Liu, Yongbo Lv, T. Thundat, Zhiyu Hu

{"title":"Power Generation on Chips: Harvesting Energy From the Sun and Cold Space","authors":"Shuai Zhang, Zhenhua Wu, Zekun Liu, Erzhen Mu, Yang Liu, Yongbo Lv, T. Thundat, Zhiyu Hu","doi":"10.1002/admt.202200478","DOIUrl":"https://doi.org/10.1002/admt.202200478","url":null,"abstract":"Environmental energy source is abundant, inexhaustible, ubiquitous, and free. However, harvesting thermal energy from the environment to generate uninterrupted electricity is still challenging. Herein, a power device to simultaneously harvest energy from the sun and cold space based on a microfabricated thermoelectric generator (TEG) integrated with a solar absorber (SA) and radiative cooling emitter (RCE) is reported. Nano‐channel arrays structure is introduced in SA to achieve high broadband light absorption (≈96%) over the entire solar spectrum. Then, a typical RCE is fabricated to demonstrate the great potential of cooperating with SA to create a continuous temperature difference for thermal energy harvesting. Furthermore, a TEG sandwiched between SA and RCE can convert the thermal energy into electricity, which is proved by a chip‐integrated micro‐TEG experimentally. What is more, two self‐generation power devices are designed, and the power generation of the reverse structure demo device (r‐TEG) is 130% of the forward one (f‐TEG) in the daytime and 260% in the nighttime. The results demonstrate a renewable and sustainable thermodynamic green resource on chips for power generation independent of time and geographical restrictions, which is vital for promoting the sun and cold space as viable energy sources beyond traditional technologies.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85409155","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}

引用次数: 6

Plant‐Based Substrate Materials for Flexible Green Electronics 柔性绿色电子器件的植物基衬底材料

Advanced Materials & Technologies Pub Date : 2022-06-22 DOI: 10.1002/admt.202200446

Youngkyu Hwang, Min Ku Kim, Ze Zhao, Bongjoong Kim, Taehoo Chang, Tengfei Fan, Mohammed Shahrudin Bin Ibrahim, Subra Suresh, Chi Hwan Lee, Nam‐Joon Cho

{"title":"Plant‐Based Substrate Materials for Flexible Green Electronics","authors":"Youngkyu Hwang, Min Ku Kim, Ze Zhao, Bongjoong Kim, Taehoo Chang, Tengfei Fan, Mohammed Shahrudin Bin Ibrahim, Subra Suresh, Chi Hwan Lee, Nam‐Joon Cho","doi":"10.1002/admt.202200446","DOIUrl":"https://doi.org/10.1002/admt.202200446","url":null,"abstract":"With the increasing use of soft and flexible electronics, there is a growing need to develop substrate materials that mitigate potential environmental risks associated with non‐degradable electronics waste from synthetic substrate materials. To address this issue, the authors develop a novel, 2D plant‐based substrate termed “sporosubstrate”, which is made of non‐allergenic natural pollen. The pollen particle has a double‐layered architecture with an ultra‐tough sporopollenin exine, and a soft cellulose intine is engineered through an eco‐friendly process. In this manner, a readily available, economical, biodegradable, and biocompatible microgel can be prepared. This microgel can be used to create a variety of flexible shapes with customized mechanical, geometrical, electronic, and functional properties and performance characteristics such as thermal, chemical, and mechanical stability and optical transparency. Moreover, the authors demonstrate here different applications of the flexible natural substrate made of pollen microgel for use in electronic devices for health monitoring and wearable wireless heating. The results of this work point to opportunities for the development of a new class of flexible green electronics based on plant‐based materials in applications such as wearable sensors, implantable devices, and soft robotics.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74740558","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}

引用次数: 0

Microstructure Engineering of Al Doped SrTiO3/TiO2 Heterostructure Nanorod Arrays Boosting Piezo‐Photocatalytic Performances Al掺杂SrTiO3/TiO2异质结构纳米棒阵列提高压电光催化性能的微结构工程

Advanced Materials & Technologies Pub Date : 2022-06-22 DOI: 10.1002/admt.202200390

Xian-Ming Chu, Xiaoqi Jiang, Hui Zhang, Cheng Wang, F. Huang, Xiaoyu Sun, Shikuo Li

{"title":"Microstructure Engineering of Al Doped SrTiO3/TiO2 Heterostructure Nanorod Arrays Boosting Piezo‐Photocatalytic Performances","authors":"Xian-Ming Chu, Xiaoqi Jiang, Hui Zhang, Cheng Wang, F. Huang, Xiaoyu Sun, Shikuo Li","doi":"10.1002/admt.202200390","DOIUrl":"https://doi.org/10.1002/admt.202200390","url":null,"abstract":"Modulating the charge‐transfer pathway is of great significance for boosting the photocatalytic efficiency of the catalysts. Herein, well‐ordered Al doping SrTiO3/TiO2 heterojunction nanorod arrays (Al‐STO/TiO2 HNRAs) via a two‐step hydrothermal protocol for efficient piezo‐photocatalysis are reported. The piezoelectric field generated by the internal polarization of Al‐STO/TiO2 HNRAs can be tailored by Al doping content, which could help to modulate the migration and separation of charge carriers. The doping of Al also makes the charge lifetime from 1.14 ns increased to 1.76 ns. Under the co‐excitation of ultrasonic and ultraviolet irradiation, the oxidation rate constant of Al‐STO/TiO2 HNRAs can reach 0.037 min−1 for the degradation of Rhodamine B molecules, which was 3.42 times higher than that of the un‐doping sample. The piezo‐potential distribution and charge migration within Al‐STO/TiO2 HNRAs were explored by piezoelectric force microscopy and COMSOL simulation. This work provides a promising solution toward modulating charge carrier migration for boosting photocatalytic activities with the assistance of mechanic vibration.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75215010","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}

引用次数: 7

Negative‐Index Acoustic Metamaterial Operating above 100 kHz in Water Using Microstructured Silicon Chips as Unit Cells 使用微结构硅芯片作为单元电池，在水中工作在100 kHz以上的负折射率声学超材料

Advanced Materials & Technologies Pub Date : 2022-06-22 DOI: 10.1002/admt.202200407

Jiaying Wang, F. Allein, Cécile Floer, N. Boechler, James Friend, O. Vázquez-Mena

{"title":"Negative‐Index Acoustic Metamaterial Operating above 100 kHz in Water Using Microstructured Silicon Chips as Unit Cells","authors":"Jiaying Wang, F. Allein, Cécile Floer, N. Boechler, James Friend, O. Vázquez-Mena","doi":"10.1002/admt.202200407","DOIUrl":"https://doi.org/10.1002/admt.202200407","url":null,"abstract":"A major challenge for negative‐index acoustic metamaterials is increasing their operational frequency to the MHz range in water for applications such as biomedical ultrasound. Herein, a novel technology to realize acoustic metamaterials in water using microstructured silicon chips as unit cells that incorporate silicon nitride membranes and Helmholtz resonators with dimensions below 100 μm fabricated using clean‐room microfabrication technology is presented. The silicon chip unit‐cells are then assembled to form periodic structures that result in a negative‐index metamaterial. Finite‐element method (FEM) simulations of the metamaterial show a negative‐index branch in the dispersion relation in the 0.25–0.35 MHz range. The metamaterial is characterized experimentally using laser‐doppler vibrometry, showing opposite phase and group velocities, a signature of negative‐index materials, and is in close agreement with FEM simulations. The experimental measurements also show that the magnitude of phase and group velocities increase as the frequency increases within the negative‐index band, confirming the negative‐index behavior of the material. Acoustic indices from –1 to –5 are reached with respect to water in the 0.25–0.35 MHz range. The use of silicon technology microfabrication to produce acoustic metamaterials for operation in water opens a new road to reach frequencies relevant for biomedical ultrasound applications.","PeriodicalId":7200,"journal":{"name":"Advanced Materials & Technologies","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79421306","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}

引用次数: 0