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951.
Light‐Emitting Diodes: Monolithic Flexible Vertical GaN Light‐Emitting Diodes for a Transparent Wireless Brain Optical Stimulator (Adv. Mater. 28/2018) 下载免费PDF全文
952.
Field‐Effect Transistors: Contact‐Engineered Electrical Properties of MoS2 Field‐Effect Transistors via Selectively Deposited Thiol‐Molecules (Adv. Mater. 18/2018) 下载免费PDF全文
953.
Shin‐Yi Tang Henry Medina Yu‐Ting Yen Chia‐Wei Chen Tzu‐Yi Yang Kung‐Hwa Wei Yu‐Lun Chueh 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(8)
A facile approach for the synthesis of Au‐ and Pt‐decorated CuInS2 nanocrystals (CIS NCs) as sensitizer materials on the top of MoS2 bilayers is demonstrated. A single surfactant (oleylamine) is used to prepare such heterostructured noble metal decorated CIS NCs from the pristine CIS. Such a feasible way to synthesize heterostructured noble metal decorated CIS NCs from the single surfactant can stimulate the development of the functionalized heterostructured NCs in large scale for practical applications such as solar cells and photodetectors. Photodetectors based on MoS2 bilayers with the synthesized nanocrystals display enhanced photocurrent, almost 20–40 times higher responsivity and the On/Off ratio is enlarged one order of magnitude compared with the pristine MoS2 bilayers‐based photodetectors. Remarkably, by using Pt‐ or Au‐decorated CIS NCs, the photocurrent enhancement of MoS2 photodetectors can be tuned between blue (405 nm) to green (532 nm). The strategy described here acts as a perspective to significantly improve the performance of MoS2‐based photodetectors with the controllable absorption wavelengths in the visible light range, showing the feasibility of the possible color detection. 相似文献
954.
Hyungkyu Han Frantisek Karlicky Sudhagar Pitchaimuthu Sun Hae Ra Shin Aiping Chen 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(40)
In spite of having several advantages such as low cost, high chemical stability, and environmentally safe and benign synthetic as well as operational procedures, the full potential of carbon dots (CDs) is yet to be explored as photosensitizers due to the challenges associated with the fabrication of well‐arrayed CDs with many other photocatalytic heterostructures. In the present study, a unique combination of metal–organic framework (MOF)‐decorated zinc oxide (ZnO) 1D nanostructures as host and CDs as guest species are explored on account of their potential application in photoelectrochemical (PEC) water splitting performance. The synthetic strategy to incorporate well‐defined nitrogen‐doped carbon dots (N‐CDs) arrays onto a zeolitic imidazolate framework‐8 (ZIF‐8) anchored on ZnO 1D nanostructures allows a facile unification of different components which subsequently plays a decisive role in improving the material's PEC water splitting performance. Simple extension of such strategies is expected to offer significant advantages for the preparation of CD‐based heterostructures for photo(electro)catalytics and other related applications. 相似文献
955.
Scalable Synthesis of Triple‐Core–Shell Nanostructures of TiO2@MnO2@C for High Performance Supercapacitors Using Structure‐Guided Combustion Waves 下载免费PDF全文
Dongjoon Shin Jungho Shin Taehan Yeo Hayoung Hwang Seonghyun Park Wonjoon Choi 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(11)
Core–shell nanostructures of metal oxides and carbon‐based materials have emerged as outstanding electrode materials for supercapacitors and batteries. However, their synthesis requires complex procedures that incur high costs and long processing times. Herein, a new route is proposed for synthesizing triple‐core–shell nanoparticles of TiO2@MnO2@C using structure‐guided combustion waves (SGCWs), which originate from incomplete combustion inside chemical‐fuel‐wrapped nanostructures, and their application in supercapacitor electrodes. SGCWs transform TiO2 to TiO2@C and TiO2@MnO2 to TiO2@MnO2@C via the incompletely combusted carbonaceous fuels under an open‐air atmosphere, in seconds. The synthesized carbon layers act as templates for MnO2 shells in TiO2@C and organic shells of TiO2@MnO2@C. The TiO2@MnO2@C‐based electrodes exhibit a greater specific capacitance (488 F g?1 at 5 mV s?1) and capacitance retention (97.4% after 10 000 cycles at 1.0 V s?1), while the absence of MnO2 and carbon shells reveals a severe degradation in the specific capacitance and capacitance retention. Because the core‐TiO2 nanoparticles and carbon shell prevent the deformation of the inner and outer sides of the MnO2 shell, the nanostructures of the TiO2@MnO2@C are preserved despite the long‐term cycling, giving the superior performance. This SGCW‐driven fabrication enables the scalable synthesis of multiple‐core–shell structures applicable to diverse electrochemical applications. 相似文献
956.
Lee Jin Hee Lee Hack-Keun Chun Dong Hyun Choi Hyunkyung Rhim Geun Bae Youn Min Hye Jeong Heondo Kang Shin Wook Yang Jung-Il Jung Heon Kim Chul Sung Park Ji Chan 《Nano Research》2019,12(10):2568-2575
Nano Research - Iron-based nanoparticles with uniform and high particle dispersion, which are supported on carbon structures, have been used for various applications. However, their preparation... 相似文献
957.
Jun-Young Cho Tae-Ho An Soo Young Shin Hwang Sun Kim Young Seok Kim Hyunick Shin Sung-Hwan Bae Miyoung Kim Seong-Hyeon Hong Chan Park 《Bulletin of Materials Science》2018,41(6):157
The effects of sintering conditions on the microstructure and mechanical properties of the sintered SiC prepared using the SiC powder recovered from the kerf loss sludge were investigated. The recovered SiC powders were consolidated by spark plasma sintering (SPS) and conventional sintering methods. The effects of sintering temperature, time and methods (SPS and conventional sintering) on the phase, grain size and density of SiC were systematically studied. The Vickers hardness of spark plasma-sintered (SPSed) samples was higher than that of conventional sintered samples due to small grain size. When holding time was increased from 10 to 30 min, the grain size and relative density of SPSed samples were also increased, which lead to the almost constant Vickers hardness by competing effects of grain size and relative density. When holding time was over 30 min, no appreciable change of the relative density and grain size were observed, which can lead to similar values of Vickers hardness. SPS process can be used to make SiC with high density and hardness at relatively low temperature compared with the conventional sintering process. 相似文献
958.
959.
Aya Shin Marc Chevalier Eleanor Laney Jonathan Pearson 《Materials at High Temperatures》2018,35(1-3):30-38
AbstractEDF Energy operates 14 advanced gas cooled reactors (AGRs) in the UK to generate electricity. CO2 gas is used as the primary coolant in the AGRs, and a range of steels are used as for the structural components: e.g. 9Cr-1Mo ferritic steels and stainless steels. These steels are susceptible to both oxidation and carburisation in CO2 dominated primary coolant gas under high pressure between 300 and 650 °C. Material degradation is a key concern for lifetime extension of the power stations, and EDF Energy and its predecessors have carried out a series of research programmes to better understand steel oxidation behaviour in AGRs and to develop more realistic lifetime prediction methodologies. These are used to secure safe and reliable operation of the AGRs. In this paper, an overview of oxidation behaviour of steels used in AGRs and some examples from the above programmes are described. 相似文献
960.
On the treatments of heterogeneities and periodic boundary conditions for isogeometric homogenization analysis 下载免费PDF全文
Seishiro Matsubara Shin‐Nosuke Nishi Kenjiro Terada 《International journal for numerical methods in engineering》2017,109(11):1523-1548
The treatments of heterogeneities and periodic boundary conditions are explored to properly perform isogeometric analysis (IGA) based on NURBS basis functions in solving homogenization problems for heterogeneous media with omni‐directional periodicity and composite plates with in‐plane periodicity. Because the treatment of the combination of different materials in IGA models is not trivial especially for periodicity constraints, the first priority is to clearly specify points at issue in the numerical modeling, or equivalently mesh generation, for IG homogenization analysis (IGHA). The most awkward, but important issue is how to generate patches for NURBS representation of the geometry of a rectangular parallelepiped unit cell to realize appropriate deformations in consideration of the convex‐hull property of IGA. The issue arises from the introduction of overlapped control points located at angular points in the heterogeneous unit cell, which must satisfy multiple point constraint (MPC) conditions associated with periodic boundary conditions (PBCs). Although two measures may be conceivable, we suggest the use of multiple patches along with double MPC that imposes PBCs and the continuity conditions between different patches simultaneously. Several numerical examples of numerical material and plate tests are presented to demonstrate the validity of the proposed strategy of IG modeling for IGHA. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献