Pub Date : 2023-10-16DOI: 10.1088/2631-7990/ad038f
Yang Sha, menghui zhu, Kun Huang, Yang Zhang, Francis Moissinac, zhizhou zhang, Dongxu Cheng, Paul Mativenga, Zhu Liu
Abstract Electrochemical production of hydrogen from water requires the development of electrocatalysts that are active, stable, and low-cost for water splitting. In comparison with conventional powder-based electrode preparation, synthesis of binder-free electrocatalytic integrated electrodes is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts. Herein, we demonstrate a laser-induced hydrothermal (LIHR) technique to grow NiMoO4 nanosheets on Nickel foam, which is then calcined under H2/Ar mixed gases to prepare the integrated electrode IE-NiMo-LR. This electrode exhibits superior hydrogen evolution reaction performance, requiring overpotentials of 59, 116 and 143 mV to achieve current densities of 100, 500 and 1000 mA cm-2. During the 350 h chronopotentiometry test at current densities of 100 and 500 mA cm-2, the overpotential remained essentially unchanged. In addition, NiFe-layered double hydroxide grown on Ni foam is fabricated with same LIHR method and coupled with IE-NiMo-IR to achieve water splitting. This combination exhibits excellent durability under industrial current density. The energy consumption and production efficiency of LIHR method are systematically compared with conventional hydrothermal method. The LIHR method significantly improved the production rate by over 19 times, while consuming only 27.78% of the total energy required by conventional hydrothermal method to achieve the same production.
摘要电化学从水中制氢需要开发出活性、稳定、低成本的水分解电催化剂。与传统的粉末电极制备相比，为了提高电催化剂的大规模应用的催化活性和长期稳定性，合成无粘结剂的电催化集成电极是非常理想的。在此，我们展示了激光诱导水热(LIHR)技术在泡沫镍上生长NiMoO4纳米片，然后在H2/Ar混合气体下煅烧制备集成电极ie - nimo4 - lr。该电极具有优异的析氢反应性能，需要59、116和143 mV的过电位才能达到100、500和1000 mA cm-2的电流密度。在100和500 mA cm-2的电流密度下进行350小时时电位测定试验，过电位基本保持不变。此外，采用相同的LIHR方法制备了Ni泡沫上生长的nife层状双氢氧化物，并结合IE-NiMo-IR实现了水裂解。这种组合在工业电流密度下表现出优异的耐久性。对LIHR法的能耗和生产效率与传统水热法进行了系统比较。LIHR法的产量提高了19倍以上，而达到相同产量所需的总能量仅为传统水热法的27.78%。
{"title":"Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting","authors":"Yang Sha, menghui zhu, Kun Huang, Yang Zhang, Francis Moissinac, zhizhou zhang, Dongxu Cheng, Paul Mativenga, Zhu Liu","doi":"10.1088/2631-7990/ad038f","DOIUrl":"https://doi.org/10.1088/2631-7990/ad038f","url":null,"abstract":"Abstract Electrochemical production of hydrogen from water requires the development of electrocatalysts that are active, stable, and low-cost for water splitting. In comparison with conventional powder-based electrode preparation, synthesis of binder-free electrocatalytic integrated electrodes is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts. Herein, we demonstrate a laser-induced hydrothermal (LIHR) technique to grow NiMoO4 nanosheets on Nickel foam, which is then calcined under H2/Ar mixed gases to prepare the integrated electrode IE-NiMo-LR. This electrode exhibits superior hydrogen evolution reaction performance, requiring overpotentials of 59, 116 and 143 mV to achieve current densities of 100, 500 and 1000 mA cm-2. During the 350 h chronopotentiometry test at current densities of 100 and 500 mA cm-2, the overpotential remained essentially unchanged. In addition, NiFe-layered double hydroxide grown on Ni foam is fabricated with same LIHR method and coupled with IE-NiMo-IR to achieve water splitting. This combination exhibits excellent durability under industrial current density. The energy consumption and production efficiency of LIHR method are systematically compared with conventional hydrothermal method. The LIHR method significantly improved the production rate by over 19 times, while consuming only 27.78% of the total energy required by conventional hydrothermal method to achieve the same production.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136079228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-13DOI: 10.1088/2631-7990/acfd68
Siqi Xie, Hongxin Zhu, Xing Zhang, Haidong Wang
Abstract Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat flow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting task. This work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices, and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.
{"title":"A brief review on the recent development of phonon engineering and manipulation at nanoscales","authors":"Siqi Xie, Hongxin Zhu, Xing Zhang, Haidong Wang","doi":"10.1088/2631-7990/acfd68","DOIUrl":"https://doi.org/10.1088/2631-7990/acfd68","url":null,"abstract":"Abstract Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat flow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting task. This work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices, and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"234 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135805978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-11DOI: 10.1088/2631-7990/acfcf2
Zhenzhen Zhou, Changru Liu, Yuting Guo, Yuan Pang, Wei Sun
Abstract Adequate vascularization is a critical determinant for the successful construction and clinical implementation of complex organotypic tissue models. Currently, low cell and vessel density and insufficient vascular maturation make vascularized organotypic tissue construction difficult, greatly limiting its use in tissue engineering and regenerative medicine. To address these limitations, recent studies have adopted pre-vascularized microtissue assembly for the rapid generation of functional tissue analogs with dense vascular networks and high cell density. In this article, we summarize the development of module assembly-based vascularized organotypic tissue construction and its application in tissue repair and regeneration, organ-scale tissue biomanufacturing, as well as advanced tissue modeling.
{"title":"Engineering vascularized organotypic tissues via module assembly","authors":"Zhenzhen Zhou, Changru Liu, Yuting Guo, Yuan Pang, Wei Sun","doi":"10.1088/2631-7990/acfcf2","DOIUrl":"https://doi.org/10.1088/2631-7990/acfcf2","url":null,"abstract":"Abstract Adequate vascularization is a critical determinant for the successful construction and clinical implementation of complex organotypic tissue models. Currently, low cell and vessel density and insufficient vascular maturation make vascularized organotypic tissue construction difficult, greatly limiting its use in tissue engineering and regenerative medicine. To address these limitations, recent studies have adopted pre-vascularized microtissue assembly for the rapid generation of functional tissue analogs with dense vascular networks and high cell density. In this article, we summarize the development of module assembly-based vascularized organotypic tissue construction and its application in tissue repair and regeneration, organ-scale tissue biomanufacturing, as well as advanced tissue modeling.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136058624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-11DOI: 10.1088/2631-7990/acfd69
Lin Gao, Mengge Wu, Xinge Yu, Junsheng Yu
Organic electrochemical transistors (OECTs) exhibit significant potential for applications in healthcare and human-machine interfaces, due to their tunable synthesis, facile deposition, and excellent biocompatibility. Expanding OECTs to the flexible devices will significantly facilitate stable contact with the skin and enable more possible bioelectronic applications. In this work, we summarize the device physics of flexible OECTs, aiming to offer a foundational understanding and guidelines for material selection and device architecture. Particular attention is paid to the advanced manufacturing approaches, including photolithography and printing techniques, which establish a robust foundation for the commercialization and large-scale fabrication. And abundantly demonstrated examples ranging from biosensors, artificial synapses/neurons, to bioinspired nervous systems are summarized to highlight the considerable prospects of smart healthcare. In the end, the challenges and opportunities are proposed for flexible OECTs. The purpose of this review is not only to elaborate on the basic design principles of flexible OECTs, but also to act as a roadmap for further exploration of wearable OECTs in advanced bio-applications.
{"title":"Device design principles and bioelectronic applications for flexible organic electrochemical transistors","authors":"Lin Gao, Mengge Wu, Xinge Yu, Junsheng Yu","doi":"10.1088/2631-7990/acfd69","DOIUrl":"https://doi.org/10.1088/2631-7990/acfd69","url":null,"abstract":"Organic electrochemical transistors (OECTs) exhibit significant potential for applications in healthcare and human-machine interfaces, due to their tunable synthesis, facile deposition, and excellent biocompatibility. Expanding OECTs to the flexible devices will significantly facilitate stable contact with the skin and enable more possible bioelectronic applications. In this work, we summarize the device physics of flexible OECTs, aiming to offer a foundational understanding and guidelines for material selection and device architecture. Particular attention is paid to the advanced manufacturing approaches, including photolithography and printing techniques, which establish a robust foundation for the commercialization and large-scale fabrication. And abundantly demonstrated examples ranging from biosensors, artificial synapses/neurons, to bioinspired nervous systems are summarized to highlight the considerable prospects of smart healthcare. In the end, the challenges and opportunities are proposed for flexible OECTs. The purpose of this review is not only to elaborate on the basic design principles of flexible OECTs, but also to act as a roadmap for further exploration of wearable OECTs in advanced bio-applications.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136058436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Diamond is a highly valuable material with diverse industrial applications, particularly in the fields of semiconductor, optics, and high-power electronics. However, its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of diamond. To address these challenges, several polishing methods have been developed for both single crystal diamond (SCD) and polycrystalline diamond (PCD), including mechanical, chemical, laser, and ion beam processing methods. In this review, the characteristics and application scope of various polishing technologies for SCD and PCD are highlighted. Specifically, various energy beam-based direct and assisted polishing technologies, such as laser polishing, ion beam polishing, plasma-assisted polishing, and laser-assisted polishing, are summarized. The current research progress, material removal mechanism, and influencing factors of each polishing technology are analyzed. Although some of these methods can achieve high material removal rates or reduce surface roughness, no single method can meet all the requirements. Finally, the future development prospects and application directions of different polishing technologies are presented.
{"title":"Energy beam-based direct and assisted polishing techniques for diamond: A review","authors":"Zhuo Li, Feng Jiang, Zhengyi Jiang, Zige Tian, Tian Qiu, Tao Zhang, Qiuling Wen, Xizhao Lu, Jing Lu, Hui Huang","doi":"10.1088/2631-7990/acfd67","DOIUrl":"https://doi.org/10.1088/2631-7990/acfd67","url":null,"abstract":"Abstract Diamond is a highly valuable material with diverse industrial applications, particularly in the fields of semiconductor, optics, and high-power electronics. However, its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of diamond. To address these challenges, several polishing methods have been developed for both single crystal diamond (SCD) and polycrystalline diamond (PCD), including mechanical, chemical, laser, and ion beam processing methods. In this review, the characteristics and application scope of various polishing technologies for SCD and PCD are highlighted. Specifically, various energy beam-based direct and assisted polishing technologies, such as laser polishing, ion beam polishing, plasma-assisted polishing, and laser-assisted polishing, are summarized. The current research progress, material removal mechanism, and influencing factors of each polishing technology are analyzed. Although some of these methods can achieve high material removal rates or reduce surface roughness, no single method can meet all the requirements. Finally, the future development prospects and application directions of different polishing technologies are presented.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136254486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-09DOI: 10.1088/2631-7990/acfcf1
Jingyao Bian, Zhiyong Liu, Ye Tao, zhongqiang Wang, Xiaoning Zhao, Ya Lin, Haiyang Xu, Yichun Liu
Abstract Spiking neural network (SNN), widely known as the third-generation neural network, has been frequently investigated due to its excellent spatiotemporal information processing capability, high biological plausibility, and low energy consumption characteristics. Analogous to the working mechanism of human brain, the SNN system transmits information through the spiking action of neurons. Therefore, artificial neurons are critical building blocks for constructing SNN in hardware. Memristors are drawing growing attention due to low consumption, high speed, and nonlinearity characteristics, which are recently introduced to mimic the functions of biological neurons. Researchers have proposed multifarious memristive materials including organic materials, inorganic materials, or even two-dimensional materials. Taking advantage of the unique electrical behavior of these materials, several neuron models are successfully implemented, such as Hodgkin–Huxley model, leaky integrate-and-fire model and integrate-and-fire model. In this review, the recent reports of artificial neurons based on memristive devices are discussed. In addition, we highlight the models and applications through combining artificial neuronal devices with sensors or other electronic devices. Finally, the future challenges and outlooks of memristor-based artificial neurons are discussed, and the development of hardware implementation of brain-like intelligence system based on SNN is also prospected.
{"title":"Advances in Memristor Based Artificial Neuron Fabrication-Materials, Models, and Applications","authors":"Jingyao Bian, Zhiyong Liu, Ye Tao, zhongqiang Wang, Xiaoning Zhao, Ya Lin, Haiyang Xu, Yichun Liu","doi":"10.1088/2631-7990/acfcf1","DOIUrl":"https://doi.org/10.1088/2631-7990/acfcf1","url":null,"abstract":"Abstract Spiking neural network (SNN), widely known as the third-generation neural network, has been frequently investigated due to its excellent spatiotemporal information processing capability, high biological plausibility, and low energy consumption characteristics. Analogous to the working mechanism of human brain, the SNN system transmits information through the spiking action of neurons. Therefore, artificial neurons are critical building blocks for constructing SNN in hardware. Memristors are drawing growing attention due to low consumption, high speed, and nonlinearity characteristics, which are recently introduced to mimic the functions of biological neurons. Researchers have proposed multifarious memristive materials including organic materials, inorganic materials, or even two-dimensional materials. Taking advantage of the unique electrical behavior of these materials, several neuron models are successfully implemented, such as Hodgkin–Huxley model, leaky integrate-and-fire model and integrate-and-fire model. In this review, the recent reports of artificial neurons based on memristive devices are discussed. In addition, we highlight the models and applications through combining artificial neuronal devices with sensors or other electronic devices. Finally, the future challenges and outlooks of memristor-based artificial neurons are discussed, and the development of hardware implementation of brain-like intelligence system based on SNN is also prospected.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135043500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.1088/2631-7990/acfc03
Bingcong Jian, Honggeng Li, Xiangnan He, Rong Wang, Hui Ying Yang, Qi Ge
Abstract Two-photon polymerization (TPP) is a cutting-edge micro/nanoscale three-dimensional (3D) printing technology based on the principle of two-photon absorption. TPP surpasses the diffraction limit in achieving feature sizes and excels in fabricating intricate 3D micro/nanostructures with exceptional resolution. The concept of 4D entails the fabrication of structures utilizing smart materials capable of undergoing shape, property, or functional changes in response to external stimuli over time. The integration of TPP and 4D printing introduces the possibility of producing responsive structures with micro/nanoscale accuracy, thereby enhancing the capabilities and potential applications of both technologies. This paper comprehensively reviews TPP-based 4D printing technology and its diverse applications. First, the working principles of TPP and its recent advancements are introduced. Second, the optional 4D printing materials suitable for fabrication with TPP are discussed. Finally, this review paper highlights several noteworthy applications of TPP-based 4D printing, including domains such as biomedical microrobots, bioinspired microactuators, autonomous mobile microrobots, transformable devices and robots, as well as anti-counterfeiting microdevices. In conclusion, this paper provides valuable insights into the current status and future prospects of TPP-based 4D printing technology, thereby serving as a guide for researchers and practitioners.
{"title":"Two-Photon Polymerization-Based 4D Printing and Its Applications","authors":"Bingcong Jian, Honggeng Li, Xiangnan He, Rong Wang, Hui Ying Yang, Qi Ge","doi":"10.1088/2631-7990/acfc03","DOIUrl":"https://doi.org/10.1088/2631-7990/acfc03","url":null,"abstract":"Abstract Two-photon polymerization (TPP) is a cutting-edge micro/nanoscale three-dimensional (3D) printing technology based on the principle of two-photon absorption. TPP surpasses the diffraction limit in achieving feature sizes and excels in fabricating intricate 3D micro/nanostructures with exceptional resolution. The concept of 4D entails the fabrication of structures utilizing smart materials capable of undergoing shape, property, or functional changes in response to external stimuli over time. The integration of TPP and 4D printing introduces the possibility of producing responsive structures with micro/nanoscale accuracy, thereby enhancing the capabilities and potential applications of both technologies. This paper comprehensively reviews TPP-based 4D printing technology and its diverse applications. First, the working principles of TPP and its recent advancements are introduced. Second, the optional 4D printing materials suitable for fabrication with TPP are discussed. Finally, this review paper highlights several noteworthy applications of TPP-based 4D printing, including domains such as biomedical microrobots, bioinspired microactuators, autonomous mobile microrobots, transformable devices and robots, as well as anti-counterfeiting microdevices. In conclusion, this paper provides valuable insights into the current status and future prospects of TPP-based 4D printing technology, thereby serving as a guide for researchers and practitioners.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135302748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and optoelectronics. The record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter, which can be further integrated into arbitrary platforms by van der Waals forces. However, due to the zero bandgap, graphene is difficult to emit light through the interband recombination of carriers like conventional semiconductors. Here, we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride (Gr/hBN) heterostructures. Electrons in biased graphene are significantly heated up to 2800 K at modest electric fields, emitting bright photons from the near-infrared to the visible spectral range. By eliminating the heat dissipation channel of the substrate, the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on SiO 2 or hBN. We further demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal equilibrium. Direct cooling of high-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface, resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical excitation. It is found that suspending the Gr/hBN heterostructures on the SiO 2 trenches significantly modifies the light emission due to the formation of the optical cavity and showed a ∼440% enhancement in intensity at the peak wavelength of 940 nm compared to the black-body thermal radiation. The demonstration of electrically driven ultrafast light emission from suspended Gr/hBN heterostructures sheds the light on applications of graphene heterostructures in photonic integrated circuits, such as broadband light sources and ultrafast thermo-optic phase modulators.
{"title":"Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures","authors":"Qiang Liu, Wei Xu, Xiaoxi Li, Tongyao Zhang, Chengbing Qin, Fang Luo, Zhihong Zhu, Shiqiao Qin, Mengjian Zhu, Kostya S. Novoselov","doi":"10.1088/2631-7990/acfbc2","DOIUrl":"https://doi.org/10.1088/2631-7990/acfbc2","url":null,"abstract":"Abstract Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and optoelectronics. The record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter, which can be further integrated into arbitrary platforms by van der Waals forces. However, due to the zero bandgap, graphene is difficult to emit light through the interband recombination of carriers like conventional semiconductors. Here, we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride (Gr/hBN) heterostructures. Electrons in biased graphene are significantly heated up to 2800 K at modest electric fields, emitting bright photons from the near-infrared to the visible spectral range. By eliminating the heat dissipation channel of the substrate, the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on SiO 2 or hBN. We further demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal equilibrium. Direct cooling of high-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface, resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical excitation. It is found that suspending the Gr/hBN heterostructures on the SiO 2 trenches significantly modifies the light emission due to the formation of the optical cavity and showed a ∼440% enhancement in intensity at the peak wavelength of 940 nm compared to the black-body thermal radiation. The demonstration of electrically driven ultrafast light emission from suspended Gr/hBN heterostructures sheds the light on applications of graphene heterostructures in photonic integrated circuits, such as broadband light sources and ultrafast thermo-optic phase modulators.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135647677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Multistable mechanical metamaterials are a type of mechanical metamaterials with special features, such as reusability, energy storage and absorption capabilities, rapid deformation, and amplified output forces. These metamaterials are usually realized by series and/or parallel of bistable units. They can exhibit multiple stable configurations under external loads and can be switched reversely among each other, thereby realizing the reusability of mechanical metamaterials and offering broad engineering applications. This paper reviews the latest research progress in the design strategy, manufacture and application of multistable mechanical metamaterials. We divide bistable structures into three categories based on their basic element types and provide the criterion of their bistability. Various manufacturing techniques to fabricate these multistable mechanical metamaterials are introduced, including mold casting, cutting, folding and three-dimensional/4D printing. Furthermore, the prospects of multistable mechanical metamaterials for applications in soft driving, mechanical computing, energy absorption and wave controlling are discussed. Finally, this paper highlights possible challenges and opportunities for future investigations. The review aims to provide insights into the research and development of multistable mechanical metamaterials.
{"title":"The Design, Manufacture and Application of Multistable Mechanical Metamaterials-A State-of-the-art Review","authors":"Rui Xu, Chuanqing Chen, Jiapeng Sun, Yulong He, Xin Li, Minghui Lu, Yanfeng Chen","doi":"10.1088/2631-7990/acf96a","DOIUrl":"https://doi.org/10.1088/2631-7990/acf96a","url":null,"abstract":"Abstract Multistable mechanical metamaterials are a type of mechanical metamaterials with special features, such as reusability, energy storage and absorption capabilities, rapid deformation, and amplified output forces. These metamaterials are usually realized by series and/or parallel of bistable units. They can exhibit multiple stable configurations under external loads and can be switched reversely among each other, thereby realizing the reusability of mechanical metamaterials and offering broad engineering applications. This paper reviews the latest research progress in the design strategy, manufacture and application of multistable mechanical metamaterials. We divide bistable structures into three categories based on their basic element types and provide the criterion of their bistability. Various manufacturing techniques to fabricate these multistable mechanical metamaterials are introduced, including mold casting, cutting, folding and three-dimensional/4D printing. Furthermore, the prospects of multistable mechanical metamaterials for applications in soft driving, mechanical computing, energy absorption and wave controlling are discussed. Finally, this paper highlights possible challenges and opportunities for future investigations. The review aims to provide insights into the research and development of multistable mechanical metamaterials.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"462 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135648091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Laser powder bed fusion (L-PBF) has attracted significant attention since its inception, providing unprecedented advantages to fabricate metallic components with complex geometry. The quality and performance of as-printed alloys is an intricate function consisting of numerous factors linking the feedstock powders, manufacturing, and post-treatment. As the starting materials, powders play a critical role in influencing the printing consistency, total fabrication cost, and mechanical properties. In consideration of its importance for L-PBF, the present review aims to review the recent progress on metallic powders for L-PBF focusing on powder characterization, powder fabrication, and powder reuse. The methods of powder characterization and fabrication were presented in the beginning by analyzing the principles and corresponding advantages and limitations. Subsequently, the effect of powder reuse on the powder characteristics and mechanical performance of L-PBF parts is analyzed focusing on steels, nickel-based superalloys, Ti and Ti alloys, and Al alloys. The evolution trend of powders and as-printed parts varies for different alloy systems based on the existing studies, which makes the proposal of a unified reuse protocol infeasible. Finally, perspectives are presented to cater to the increasing applications of AM technologies for future investigations. The present state-of-the-art work can pave the way for the broad industrial applications of L-PBF by enhancing printing consistency and reducing the total cost from the perspective of powders.
{"title":"Characterization, preparation, and reuse of metallic powders for laser powder bed fusion: A review","authors":"Xiaoyu Sun, Minan Chen, Tingting Liu, Kai Zhang, Huiliang Wei, Zhiguang Zhu, Wenhe Liao","doi":"10.1088/2631-7990/acfbc3","DOIUrl":"https://doi.org/10.1088/2631-7990/acfbc3","url":null,"abstract":"Abstract Laser powder bed fusion (L-PBF) has attracted significant attention since its inception, providing unprecedented advantages to fabricate metallic components with complex geometry. The quality and performance of as-printed alloys is an intricate function consisting of numerous factors linking the feedstock powders, manufacturing, and post-treatment. As the starting materials, powders play a critical role in influencing the printing consistency, total fabrication cost, and mechanical properties. In consideration of its importance for L-PBF, the present review aims to review the recent progress on metallic powders for L-PBF focusing on powder characterization, powder fabrication, and powder reuse. The methods of powder characterization and fabrication were presented in the beginning by analyzing the principles and corresponding advantages and limitations. Subsequently, the effect of powder reuse on the powder characteristics and mechanical performance of L-PBF parts is analyzed focusing on steels, nickel-based superalloys, Ti and Ti alloys, and Al alloys. The evolution trend of powders and as-printed parts varies for different alloy systems based on the existing studies, which makes the proposal of a unified reuse protocol infeasible. Finally, perspectives are presented to cater to the increasing applications of AM technologies for future investigations. The present state-of-the-art work can pave the way for the broad industrial applications of L-PBF by enhancing printing consistency and reducing the total cost from the perspective of powders.","PeriodicalId":52353,"journal":{"name":"International Journal of Extreme Manufacturing","volume":"145 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136306445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：