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Salt-assisted chemical vapor deposition of two-dimensional materials 被引量:10
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作者 Wei Han Kailang Liu +5 位作者 Sanjun Yang Fakun Wang Jianwei Su Bao Jin Huiqiao Li Tianyou Zhai 《Science China Chemistry》 SCIE EI CAS CSCD 2019年第10期1300-1311,共12页
Two-dimensional(2D) materials with atomic thickness are promising candidates for the applications in future semiconductor devices, owing to their fascinating physical properties and superlative optoelectronic performa... Two-dimensional(2D) materials with atomic thickness are promising candidates for the applications in future semiconductor devices, owing to their fascinating physical properties and superlative optoelectronic performance. Chemical vapor deposition(CVD) is considered to be an efficient method for large-scale preparation of 2D materials toward practical applications.However, the high melting points of metal precursors and the thermodynamics instabilities of metastable phases limit the direct CVD synthesis of plenty of 2D materials. The salt has recently been introduced into the CVD process, which proved to be effective to address these issues. In this review, we highlighted the latest progress in the salt-assisted CVD growth of 2D materials, including layered and non-layered crystals. Firstly, strategies of adding salts are summarized. Then, the salt-assisted growth of various layered materials is presented, emphasizing on the transition metal chalcogenides of stable and metastable phases. Furthermore, strategies to grow ultrathin non-layered materials are discussed. We provide viewpoints into the techniques of using salt, the effects of salt, and the growth mechanisms of 2D crystals. Finally, we offer the challenges to be overcome and further research directions of this emerging salt-assisted CVD technique. 展开更多
关键词 salt-assisted chemical vapor deposition 2D MATERIALS transition metal DICHALCOGENIDES non-layered MATERIALS
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Molten metal-organic complex to synthesize versatile ultrathin nonlayered oxides 被引量:1
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作者 Kaisi Liu Jiabin Wu +7 位作者 Qun Li Hongrun Jin Yongxin Luo Bei Qi Simin Dai Jianquan Zhao Liang Huang Jun Zhou 《Nano Research》 SCIE EI CSCD 2024年第4期3147-3155,共9页
Two-dimensional(2D)materials have attracted a great deal of research interest because of their unique electrical,magnetic,optical,mechanical,and catalytic properties for various applications.To date,however,it is stil... Two-dimensional(2D)materials have attracted a great deal of research interest because of their unique electrical,magnetic,optical,mechanical,and catalytic properties for various applications.To date,however,it is still difficult to fabricate most functional oxides as 2D materials unless they have a layered structure.Herein,we report a one-step universal strategy for preparing versatile non-layered oxide nanosheets by directly annealing the mixture of metal nitrate and dimethyl imidazole(2-MI).The 2-MI plays the key role for 2D oxides since 2-MI owns a very low molten point and sublimation temperature,in which its molten liquid can coordinate with metal ions,forming a metal-organic framework,and easily puffing by its gas molecules.A total of 17 materials were prepared by this strategy,including non-layered metal oxide nanosheets as well as metal/metal oxide loaded nitrogen-doped carbon nanosheets.The as-prepared cobalt particle-loaded nitrogen-doped carbon nanosheets(Co@N/C)exhibit remarkable bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalytic activity and durability.Besides,the Zn-air battery utilizing a Co@N/C catalyst exhibits high power density of 174.3 mW·cm^(-2).This facile strategy opens up a new way for large-scale synthesis of 2D oxides that holds great potential to push 2D oxides for practical applications. 展开更多
关键词 non-layered oxide nanosheet metal/metal oxide@N/C oxygen evolution reaction(OER) oxygen reduction reaction(ORR) Zn-air battery
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Anomalous magnetic property and broadband photodetection in ultrathin non-layered manganese selenide semiconductor
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作者 Ye Zhao Ruilong Yang +5 位作者 Ke Yang Jiarui Dou Xiaoting Yang Jinzhong Guo Guowei Zhou Xiaohong Xu 《Nano Research》 SCIE EI CSCD 2024年第9期8578-8584,共7页
Two-dimensional(2D)semiconductors with intrinsic ferromagnetism are highly desirable for potential applications in nextgeneration spintronic and optoelectronic devices.However,controllable synthesis of intrinsic 2D ma... Two-dimensional(2D)semiconductors with intrinsic ferromagnetism are highly desirable for potential applications in nextgeneration spintronic and optoelectronic devices.However,controllable synthesis of intrinsic 2D magnetic semiconductor on a substrate is still a challenging task.Herein,large-area 2D non-layered rock salt(α-phase)MnSe nanosheets were grown on mica substrates,with the thickness changing from 54.2 to 0.9 nm(one unit cell),by chemical vapour deposition.The X-ray diffraction,Raman spectroscopy,transmission electron microscopy,and X-ray photoelectron spectroscopy measurements confirmed that the resulting 2Dα-MnSe nanosheets were obtained as high-quality single crystals.The magnetic hysteresis loops and synchrotron X-ray measurements directly indicated the anomalous magnetic properties inα-MnSe nanosheets.Comprehensive analysis of the reasons for magnetic property revealed that the low-temperature phase transition,small number of stacking differences in crystals,and surface weak oxidation in(111)-orientedα-MnSe were the main mechanisms.Furthermore,α-MnSe nanosheets exhibited broadband photoresponse from 457 to 671 nm with an outstanding detectivity and responsivity behaviours.This study presents the detailed growth process of ultrathin 2D magnetic semiconductorα-MnSe,and its outstanding magnetic properties and broadband photodetection,which provide an excellent platform for magneto-optical and magneto-optoelectronic research. 展开更多
关键词 two-dimensional material anomalous magnetism broadband photodetection α-phase MnSe non-layered crystal
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Magnetic proximity effect in the two-dimensional ε-Fe_(2)O_(3)/NbSe_(2)heterojunction
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作者 车冰玉 胡国静 +17 位作者 朱超 郭辉 吕森浩 刘轩冶 吴康 赵振 潘禄禄 祝轲 齐琦 韩烨超 林晓 李子安 申承民 鲍丽宏 刘政 周家东 杨海涛 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期492-497,共6页
Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie te... Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie temperature and instability in air,it is hard to realize practical applications for the reported layered magnetic materials at present.In this paper,we developed a space-confined chemical vapor deposition method to synthesize ultrathin air-stable ε-Fe_(2)O_(3) nanosheets with Curie temperature above 350 K.The ε-Fe_(2)O_(3)/NbSe_(2) heterojunction was constructed to study the magnetic proximity effect on the superconductivity of the NbSe_(2) multilayer.The electrical transport results show that the subtle proximity effect can modulate the interfacial spin–orbit interaction while undegrading the superconducting critical parameters.Our work paves the way to construct 2D heterojunctions with ultrathin nonlayered materials and layered van der Waals(vdW)materials for exploring new physical phenomena. 展开更多
关键词 two-dimensional heterojunctions magnetic proximity effect non-layered magnetic nanosheet spin-orbit interaction
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一种应用于不可分层LDPC码的并行分层译码算法 被引量:4
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作者 郭琨 黑勇 +1 位作者 周玉梅 乔树山 《电子与信息学报》 EI CSCD 北大核心 2010年第8期1956-1960,共5页
该文针对"不可分层"LDPC码无法利用分层算法进行译码的问题,提出了一种并行分层置信度传播(Parallel-Layered Belief-Propagation,PLBP)译码算法。与传统分层算法不同,该算法在译码时并行进行各层更新,串行进行层内各行更新... 该文针对"不可分层"LDPC码无法利用分层算法进行译码的问题,提出了一种并行分层置信度传播(Parallel-Layered Belief-Propagation,PLBP)译码算法。与传统分层算法不同,该算法在译码时并行进行各层更新,串行进行层内各行更新。这种译码机制使得同一变量节点在各层内不同时进行更新,从而实现各变量节点在一次迭代中分层递进更新的算法目标。仿真表明,在不增加译码复杂度的情况下,该文提出的PLBP算法与传统的洪水算法相比,误码性能更优,而且所需要的平均迭代次数降低了约50%。此外,PLBP算法采用了合并的节点更新运算,最终使该算法达到的译码速度约为洪水算法的4倍。 展开更多
关键词 LDPC码 不可分层 并行分层译码 中国移动多媒体广播
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Thickness-dependent highly sensitive photodetection behavior of lead-free all-inorganic CsSnBr_(3) nanoplates 被引量:3
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作者 Dong Liu Yan-Xue Yin +6 位作者 Feng-Jing Liu Cheng-Cheng Miao Xin-Ming Zhuang Zhi-Yong Pang Ming-Sheng Xu Ming Chen Zai-Xing Yang 《Rare Metals》 SCIE EI CAS CSCD 2022年第5期1753-1760,共8页
Non-layered two-dimensional(2D) lead-free all-inorganic perovskites nanoplates have recently attracted considerable attention in photodetectors;however, the indepth investigation of thickness on photodetection perform... Non-layered two-dimensional(2D) lead-free all-inorganic perovskites nanoplates have recently attracted considerable attention in photodetectors;however, the indepth investigation of thickness on photodetection performance is still lacking. In this work, by constructing the famous metal-semiconductor-metal photodetectors, the photodetection behaviors of thickness-controlled CsSnBr;nanoplates are investigated systematically. Ni electrodes are adopted for ensuring the good ohmic contact behaviors of as-fabricated photodetectors. With the increase in thickness, the photodetection performances improve accordingly, such as photocurrent increases from 0.22 to 19.40 nA, responsivity increases from 72.9 to 4893.7 mA·W^(-1), rise/decay time decreases from 11/35 to 3/10 ms, respectively. Notability, the dark current also increases with the increase in thickness, making the further investigation on the reduction in dark current meaningful.All of the as-fabricated photodetectors are stable, suggesting the careful thickness selection in next-generation high-performance lead-free all-inorganic perovskites photodetectors. 展开更多
关键词 Thickness PHOTODETECTION Lead-free all-inorganic perovskites non-layered two-dimensional perovskites CsSnBr3 nanoplates
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Dual-metal precursors for the universal growth of non-layered 2D transition metal chalcogenides with ordered cation vacancies 被引量:2
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作者 Junyang Tan Zongteng Zhang +16 位作者 Shengfeng Zeng Shengnan Li Jingwei Wang Rongxu Zheng Fuchen Hou Yinping Wei Yujie Sun Rongjie Zhang Shilong Zhao Huiyu Nong Wenjun Chen Lin Gan Xiaolong Zou Yue Zhao Junhao Lin Bilu Liu Hui-Ming Cheng 《Science Bulletin》 SCIE EI CAS CSCD 2022年第16期1649-1658,M0004,共11页
Two-dimensional(2D)transition metal chalcogenides(TMCs)are promising for nanoelectronics and energy applications.Among them,the emerging non-layered TMCs are unique due to their unsaturated dangling bonds on the surfa... Two-dimensional(2D)transition metal chalcogenides(TMCs)are promising for nanoelectronics and energy applications.Among them,the emerging non-layered TMCs are unique due to their unsaturated dangling bonds on the surface and strong intralayer and interlayer bonding.However,the synthesis of non-layered 2D TMCs is challenging and this has made it difficult to study their structures and properties at thin thickness limit.Here,we develop a universal dual-metal precursors method to grow non-layered TMCs in which a mixture of a metal and its chloride serves as the metal source.Taking hexagonal Fe_(1-x)S as an example,the thickness of the Fe_(1-x)S flakes is down to 3 nm with a lateral size of over 100 μm.Importantly,we find ordered cation Fe vacancies in Fe_(1-x)S,which is distinct from layered TMCs like MoS_(2) where anion vacancies are commonly observed.Low-temperature transport measurements and theoretical calculations show that 2D Fe_(1-x)S is a stable semiconductor with a narrow bandgap of60 meV.In addition to Fe_(1-x)S,the method is universal in growing various non-layered 2D TMCs containing ordered cation vacancies,including Fe_(1-x)Se,Co_(1-x)S,Cr_(1-x)S,and V_(1-x)S.This work paves the way to grow and exploit properties of non-layered materials at 2D thickness limit. 展开更多
关键词 non-layered two-dimensional materials Transition metal chalcogenides Dual-metal precursors Chemical vapor deposition Ordered cation vacancies
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基于FPGA的QC-LDPC码分层译码器设计 被引量:3
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作者 彭阳阳 仰枫帆 《无线电工程》 2014年第2期17-20,共4页
针对抑制短环法构造的不可分层QC-LDPC码无法采用部分并行译码结构的问题,基于FPGA设计了一种新型的分层译码器。实验仿真证明:相对于传统的分层译码算法,改进后的译码算法具有更好的性能表现。选用Altera公司Strtix II系列的EP2S60F48... 针对抑制短环法构造的不可分层QC-LDPC码无法采用部分并行译码结构的问题,基于FPGA设计了一种新型的分层译码器。实验仿真证明:相对于传统的分层译码算法,改进后的译码算法具有更好的性能表现。选用Altera公司Strtix II系列的EP2S60F484C3器件,实现码长为2 048、码率为3/4的(3,12)的不可分层QC-LDPC码分层译码器的布局布线,综合优化。译码器在90 MHz的工作频率下,最大译码迭代次数为5时,吞吐量可达到93.85 Mbps。 展开更多
关键词 QC—LDPC码 抑制短环构造 不可分层 FPGA
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Recent advances in two-dimensional layered and non-layered materials hybrid heterostructures
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作者 Haixin Ma Yanhui Xing +3 位作者 Boyao Cui Jun Han Binghui Wang Zhongming Zeng 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第10期231-246,共16页
With the development of Moore's law, the future trend of devices will inevitably be shrinking and integration to further achieve size reduction. The emergence of new two-dimensional non-layered materials(2DNLMs) n... With the development of Moore's law, the future trend of devices will inevitably be shrinking and integration to further achieve size reduction. The emergence of new two-dimensional non-layered materials(2DNLMs) not only enriches the 2D material family to meet future development, but also stimulates the global enthusiasm for basic research and application technologies in the 2D field. Van der Waals(vd W) heterostructures, in which two-dimensional layered materials(2DLMs)are physically stacked layer by layer, can also occur between 2DLMs and 2DNLMs hybrid heterostructures, providing an alternative platform for nanoelectronics and optoelectronic applications. Here, we outline the recent developments of2DLMs/2DNLMs hybrid heterostructures, with particular emphasis on major advances in synthetic methods and applications. And the categories and crystal structures of 2DLMs and 2DNLMs are also shown. We highlight some promising applications of the heterostructures in electronics, optoelectronics, and catalysis. Finally, we provide conclusions and future prospects in the 2D materials field. 展开更多
关键词 2D layered materials 2D non-layered materials van der Waals heterostructure applications
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基于FPGA的不可分层LDPC码译码器
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作者 江涛 仰枫帆 《无线电通信技术》 2012年第1期25-28,62,共5页
针对不可分层LDPC码无法采用分层译码算法的问题,设计了一种新型的LDPC码分层译码器。与传统分层译码器的结构不同,新结构在各层间进行并行更新,各层内进行串行更新。通过保证在不同分层的同一变量节点不同时进行更新,达到分层译码算法... 针对不可分层LDPC码无法采用分层译码算法的问题,设计了一种新型的LDPC码分层译码器。与传统分层译码器的结构不同,新结构在各层间进行并行更新,各层内进行串行更新。通过保证在不同分层的同一变量节点不同时进行更新,达到分层译码算法分层递进更新的目标。选用Altera公司的CycloneⅢ系列EP3C120器件,实现码率3/4,码长8 192的(3,12)规则不可分层QC-LDPC码译码器的布局布线,在最大迭代次数为5次时,最高时钟频率可以达到45.44 MHz,吞吐量可以达到47.6 Mbps。 展开更多
关键词 QC—LDPC码 不可分层 分层译码 FPGA
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High-yield production of non-layered 2D carbon complexes:Thickness manipulation and carbon nanotube branches for enhanced lithium storage properties
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作者 Dong Wang Shuai Qi +8 位作者 Yao Qiu Rui Zhang Qiang Zhang Shulong Liu Chunjie Zhang Ziyao Chen Hong Pan Jun Cao Guangwu Wen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期19-29,I0002,共12页
Non-layered two-dimensional(2 D)carbon complexes manifest great potential in energy-related applications owing to their exotic electronic structures,large electrochemically active surface,and intriguing synergistic ef... Non-layered two-dimensional(2 D)carbon complexes manifest great potential in energy-related applications owing to their exotic electronic structures,large electrochemically active surface,and intriguing synergistic effects.However,reliable method for mass production and thickness manipulation of 2 D carbon complexes remains great challenges.Here,inspired by blowing chewing gum into bubbles,a“tailored gel expanding"strategy is proposed for high-yield synthesis of non-layered 2 D carbon complexes with tailored thickness from~12 nm to~1 lm,by controllable pyrolysis of metal-polymeric gel with adequate crosslinking degree.The key feature for thickness manipulation is introducing NH4 NO3 in sol-gel process,which tailors the expansion behavior of gel precursor during subsequent pyrolysis.Various of 2 D sheets with intimately coupled N,O-doped carbon(NOC)and Ni Co-based(Ni Co,(Ni Co)S_(2),(Ni Co)Se_(2),Ni Co_(2)O_(4),(Ni Co)(PO_(3))_(2))nanocrystals are obtained on a large scale and without any impurities.Moreover,these 2 D products are branched with in-situ grown CNTs on the surface,accelerating electrons transfer and preventing the nanosheets from stacking.As a demonstration,the 2 D(Ni Co)S_(2)/NOC with optimized thickness manifests excellent lithium storage properties in both half and full cells.This method paves a new path for massive and controlled production of non-layered 2 D materials with tailored thickness and robust structure stability for energy-related applications. 展开更多
关键词 Two-dimensional materials non-layered structures Thickness manipulation Carbon nanotubes Lithium-ion batteries
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非层状过渡金属碳化物在能源存储与转换中的应用进展
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作者 高银红 南旭 +6 位作者 阳尧 孙兵 徐文莉 Wandji Djouonkep Lesly Dasilva 李轩科 李艳军 张琴 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2021年第4期751-778,共28页
非层状过渡金属碳化物(NL-TMCs)具有多样化的形貌结构和可调控的化学计量比,从而表现出高比容量、高导电性和良好的稳定性等优异的电/催化性能。因此,本文对NL-TMCs在储能与转换领域的最新进展进行了总结。首先阐述了NL-TMCs的可控制备... 非层状过渡金属碳化物(NL-TMCs)具有多样化的形貌结构和可调控的化学计量比,从而表现出高比容量、高导电性和良好的稳定性等优异的电/催化性能。因此,本文对NL-TMCs在储能与转换领域的最新进展进行了总结。首先阐述了NL-TMCs的可控制备策略,其中包括碳热还原法、化学气相沉积法、模板辅助法、水热/溶剂热法。其次,探讨了NL-TMCs在锂离子电池、锂硫电池、全水解等能源储存与转换领域中应用,并对其未来的发展方向进行了展望,为合理地设计和构建NL-TMCs以供实际应用提供了理论基础。 展开更多
关键词 非层状 过渡金属碳化物 电化学 能源转换 能源存储
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塔里木盆地顺北地区海相超深碳酸盐岩油气勘探物探技术需求与创新应用 被引量:9
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作者 漆立新 《石油物探》 CSCD 北大核心 2023年第3期381-394,共14页
塔里木盆地顺北地区海相超深层碳酸盐岩是塔里木盆地油气勘探的重点领域之一。经过地震采集、处理成像、量化识别和地质工程一体化解释的系统攻关,逐渐形成了高密度、高精度、面向缝洞体的三维地震采集技术;宽频带、高保真全波场地震处... 塔里木盆地顺北地区海相超深层碳酸盐岩是塔里木盆地油气勘探的重点领域之一。经过地震采集、处理成像、量化识别和地质工程一体化解释的系统攻关,逐渐形成了高密度、高精度、面向缝洞体的三维地震采集技术;宽频带、高保真全波场地震处理技术;叠前宽方位分析、各向异性检测、可视化等多维度解释技术。但作为典型的非层状油气藏,塔里木盆地顺北地区海相超深碳酸盐岩油气地震勘探理论与地震勘探实践仍面临全方位的挑战,未来应进一步加强物探技术攻关,包括进一步完善地震散射波传播与成像理论;试验以“共中心点离散化、近偏高覆盖、多观测系统”为主的地震采集技术;重新认识噪声,实现多态式地震波处理和全波场地震成像;积极探索智能化解释技术,综合岩石物理分析与正演模拟、多态式的叠前反演与地震属性分析,精细描述缝洞体及其内幕。这些技术对支撑顺北地区持续重大突破和持续发展,以及对国内外超深层碳酸盐岩勘探和非层状油气藏勘探具有借鉴意义。 展开更多
关键词 超深碳酸盐岩油气藏 断控缝洞体 非层状油气藏勘探 地震波场 散射波地震采集 多态式地震处理成像 地震散射波识别和量化表征
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纤维增韧地聚物混凝土力学性能与微观结构 被引量:3
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作者 黄华 郭梦雪 +1 位作者 于基宁 杨世林 《建筑科学与工程学报》 CAS 北大核心 2023年第4期12-23,共12页
为改善地聚物延性较差的缺点,采用镀铜微细钢纤维与聚丙烯纤维制备了不同纤维类型、布置形式与体积掺量的纤维增韧粉煤灰-矿渣基地聚物混凝土,对其力学性能进行了试验研究,并通过扫描电子显微镜从微观层面解释了不同布置形式的纤维增韧... 为改善地聚物延性较差的缺点,采用镀铜微细钢纤维与聚丙烯纤维制备了不同纤维类型、布置形式与体积掺量的纤维增韧粉煤灰-矿渣基地聚物混凝土,对其力学性能进行了试验研究,并通过扫描电子显微镜从微观层面解释了不同布置形式的纤维增韧机理。结果表明:钢纤维与聚丙烯纤维分别以拔出与断裂的形式有效地阻止地聚物混凝土裂缝的发展;对于整体式单掺钢纤维与整体式混掺纤维地聚物混凝土试样,其劈裂抗拉强度与抗折强度均得到显著提升;层布式钢纤维地聚物混凝土试样可达到与整体式纤维地聚物混凝土相当的力学性能且前者的纤维用量仅为后者的40%左右;与整体式纤维增韧机理不同,层布式钢纤维地聚物混凝土试样中双层钢纤维相当于“双层弹性板”,除了聚丙烯纤维以及钢纤维的“桥接”作用,还可与基体周围的钢纤维互相交叉形成网状结构,钢纤维网状结构之间的相互作用限制了纤维的相对位移,显著提升了试样的力学性能。 展开更多
关键词 地聚物混凝土 纤维增韧 力学性能 微观结构 整体式纤维 层布式纤维
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非层状二维CdSe的制备及厚度对带隙的影响
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作者 李婷 张文婷 +3 位作者 王红艳 李秀梅 雷子煊 夏晓凤 《原子与分子物理学报》 北大核心 2024年第5期153-158,共6页
二维半导体材料的天然带隙有望弥补石墨烯的零带隙缺陷,打破后者在场效应晶体管、开关器件、逻辑电路等领域的应用瓶颈. 相较于层状半导体材料,非层状半导体材料多以较强的离子键/共价键结合,且各向同性,因此要获取其二维结构存在一定挑... 二维半导体材料的天然带隙有望弥补石墨烯的零带隙缺陷,打破后者在场效应晶体管、开关器件、逻辑电路等领域的应用瓶颈. 相较于层状半导体材料,非层状半导体材料多以较强的离子键/共价键结合,且各向同性,因此要获取其二维结构存在一定挑战. 本论文通过化学气相沉积法实现了非层状CdSe在云母衬底上的二维各向异性生长. 详细表征了二维CdSe的微观形貌、晶体结构和光学特性等. 结果表明,样品具有显著的光致发光 (PL )效应,说明厚度减薄至纳米级时不会破坏CdSe的直接带隙属性. 此外,随着厚度减小,样品的PL峰逐渐蓝移. 为了进一步解释该现象,采用基于密度泛函理论的第一性原理计算方法,研究了不同厚度的CdSe的能带结构,结果显示均为直接带隙,且随厚度减小,带隙值增大,与实验现象吻合. 由此可知,通过生长参数调控二维CdSe的厚度,即可实现对其带隙的有效调控,这对相关光电器件的性能提升具有指导意义. 展开更多
关键词 非层状半导体材料 二维CdSe 化学气相沉积 带隙 第一性原理
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电子束辐照诱导二维氧化铟纳米片生长的原位电镜研究
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作者 朱亚彤 张昊 +1 位作者 徐涛 孙立涛 《电子显微学报》 CAS CSCD 北大核心 2023年第3期275-282,共8页
非层状二维材料因其新颖的二维特性在电子学、光电子学、催化、能量储存和转换等领域具有广泛的应用前景。然而,其现有的合成方法都无法精确地控制材料的形貌和尺寸,且对材料潜在的生长机制尚不明确。本文利用透射电子显微镜中的高能电... 非层状二维材料因其新颖的二维特性在电子学、光电子学、催化、能量储存和转换等领域具有广泛的应用前景。然而,其现有的合成方法都无法精确地控制材料的形貌和尺寸,且对材料潜在的生长机制尚不明确。本文利用透射电子显微镜中的高能电子束,辐照诱导了硒化铟纳米片表面氧化铟纳米晶粒的产生,并在原子尺度观察了氧化铟纳米片的原位生长过程。实验发现,氧化铟纳米片沿着{222}晶面以“逐层生长”的方式形成特定的结构,且原子优先在台阶处成核以降低生长过程中的表面能。这一研究表明,电子束辐照可以作为一种有效的工具来制备氧化铟等非层状二维材料,为二维纳米结构的可控制备提供实验和理论依据。 展开更多
关键词 非层状二维材料 电子束辐照 硒化铟 氧化铟 原位生长
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二维非层状过渡金属氧化物的制备及研究进展 被引量:1
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作者 朱成瑶 王园园 王万杰 《微纳电子技术》 北大核心 2020年第10期823-834,共12页
近年来,二维非层状材料由于其原子级厚度、大比表面积和高活性位点数量多等结构特点而受到广泛关注。简单介绍了二维非层状材料,重点综述了表面氧化法、气相沉积法、自组装法、模板辅助合成法和溶剂热法等二维非层状过渡金属氧化物的常... 近年来,二维非层状材料由于其原子级厚度、大比表面积和高活性位点数量多等结构特点而受到广泛关注。简单介绍了二维非层状材料,重点综述了表面氧化法、气相沉积法、自组装法、模板辅助合成法和溶剂热法等二维非层状过渡金属氧化物的常见制备方法,并对其在超级电容器、催化剂、电池、传感器等领域的应用进行了概述。最后,总结了二维非层状过渡金属氧化物研究领域存在的挑战并对其未来研究方向进行了展望,指出优化现有制备方法和发展新方法、与其他材料复合构建二维异质结、加强生长机理研究和拓展应用探索将成为该领域的主要研究方向。 展开更多
关键词 二维材料 非层状材料 过渡金属氧化物(TMO) 纳米材料 超级电容 传感器
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一种新型高精度钢板超声检测系统的应用
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作者 魏克同 龚健 +2 位作者 苏志 汪超 王俊 《焊管》 2020年第8期51-55,共5页
为了严格控制大直径直缝双面埋弧焊管的原材料质量,有效检测出钢板内部的分层缺陷和非分层缺陷,设计了一种新型高精度钢板超声检测系统。重点介绍了该系统对钢板板边50 mm范围内的裂纹、收缩孔隙和超标母材夹杂物等非分层缺陷,以及钢板... 为了严格控制大直径直缝双面埋弧焊管的原材料质量,有效检测出钢板内部的分层缺陷和非分层缺陷,设计了一种新型高精度钢板超声检测系统。重点介绍了该系统对钢板板边50 mm范围内的裂纹、收缩孔隙和超标母材夹杂物等非分层缺陷,以及钢板板边100 mm范围内的超标母材分层缺陷和钢板中部超标的母材分层缺陷的检测方法。应用表明,新型高精度钢板超声波检测系统大大提高了钢板分层缺陷和非分层缺陷的检出率和钢板超声波自动检测的准确性,为钢板在线检测提供了新的思路。 展开更多
关键词 超声波检测系统 分层缺陷 非分层缺陷 纵波探头 横波探头 检测盲区 通道 模块
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基于全无机钙钛矿纳米晶体与二维非层状硒硫化镉异质结的高性能光电探测器研究
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作者 彭明发 况亚伟 洪学鹍 《常熟理工学院学报》 2022年第2期1-4,共4页
本文通过能带工程设计并构筑基于全无机CsPbBr;钙钛矿纳米晶体与二维非层状硒硫化镉异质结的高性能光电探测器.异质结光电探测器展现出超高的明暗电流比值、高的响应度和大的探测率.通过稳态荧光光谱、时间分辨荧光光谱及开尔文探针显... 本文通过能带工程设计并构筑基于全无机CsPbBr;钙钛矿纳米晶体与二维非层状硒硫化镉异质结的高性能光电探测器.异质结光电探测器展现出超高的明暗电流比值、高的响应度和大的探测率.通过稳态荧光光谱、时间分辨荧光光谱及开尔文探针显微镜等表征手段研究了异质结界面处的载流子传输动力学和传输机制.异质结光电探测器性能的增强归因于钙钛矿纳米晶体与二维非层状硒硫化镉之间有效的载流子传输能力. 展开更多
关键词 全无机钙钛矿 二维硒硫化镉 异质结 能带工程 光电探测器
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新型二维铜族硫族化合物的研究进展
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作者 刘涵 高蕾 +2 位作者 薛宇飞 叶宇娇 曾春华 《人工晶体学报》 CAS 北大核心 2022年第8期1493-1510,共18页
二维材料因其纳米级尺寸、超凡的电子特性、出色的机械性能等,被视为下一代信息器件的理想材料。随着外延生长等自下而上制备方法以及材料计算方法的发展和提高,越来越多的体相非层状的二维材料被制备和发现。近年来在信息器件等领域具... 二维材料因其纳米级尺寸、超凡的电子特性、出色的机械性能等,被视为下一代信息器件的理想材料。随着外延生长等自下而上制备方法以及材料计算方法的发展和提高,越来越多的体相非层状的二维材料被制备和发现。近年来在信息器件等领域具有应用潜力的体相非层状的二维铜族(11族)硫族化合物得到广泛关注,铜族元素位于化学元素周期表中的11族,主要包括铜、银和金等元素。本文综述了二维铜族硫族化合物的研究进展,以化学计量比为主线,将二维铜族硫族化合物分为MX单层(M=Cu,Ag,Au;X=O,S,Se,Te)、M_(2)X单层以及其他化学计量比的铜族硫族化合物单层。从实验合成和理论模拟两个角度出发,对二维铜族硫族化合物原子结构、能带结构、电学特性等进行介绍。从现有的报道来看,体相非层状的新型二维铜族硫族化合物不仅包含半导体、金属等电子性质,还表现出拓扑、磁性等丰富的新奇物性,是一类值得关注的新型二维功能材料。 展开更多
关键词 二维材料 铜族硫族化合物 体相非层状 电子结构 第一性原理计算 密度泛函理论
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