检索结果-内蒙古大学图书馆

Directional transport for efficient catalysis

学校读者我要写书评

暂无评论

Matter 2023年第3期6卷 674-676页

作者： Jie Ying Mark D. Symes Xiao-Yu Yang School of Chemical Engineering and Technology Sun Yat-sen University Zhuhai 519082 China WestCHEM School of Chemistry University of Glasgow University Avenue Glasgow G12 8QQ UK State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Joint Laboratory for Marine Advanced Materials in National Laboratory for Marine Science and Technology (Qingdao) Wuhan University of Technology Wuhan 430070 China School of Engineering and Applied Sciences Harvard University Cambridge MA 02138 USA

Directional transport is a common phenomenon in nature that underpins the efficient completion of a number of complex and elaborate processes. However, its application to the design of catalysts is challenging as a result of a lack of understanding of the basic design principles in operation. To this end, it has now been demonstrated that a porous covalent organic framework material with a mesoporous aperture substantially promotes the transport ability of oxygen and consequently increases the catalytic activity of commercial Pt/C catalysts in a fuel cell.

关键词：

The Effects of Diatom Frustules Shapes and Purity on the Performance of Diatom-Based Lithium Ion Silicon Carbon Anode materials

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Liu, Yuhang Ren, Zijie Zhou, Liang Jiang, Yuqian Gao, Huimin An, Qinyou Xu, Longhua School of Resources and Environmental Engineering Wuhan University of Technology Hubei Wuhan430070 China Key Laboratory of Hubei Province for Mineral Resources Processing Environment Wuhan430070 China State Key Laboratory of Environment-friendly Energy Materials Sichuan Mianyang621010 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Southwest University of Science and Technology China

Diatomite has been widely studied as a silicon source. Three kinds of diatomite with different diatom frustules or different purities were reduced to porous silicon. The porous silicon coated carbon was prepared into positive electrode materials for battery cycle performance test. The test results showed that the Si/C composites anode material obtained by the reduction of diatomite with high purity of SiO2 has a high initial capacity, 2491mAhg-1, while that with low SiO2 purity is only 1412mAhg-1. The capacity retention rate of Si/C material prepared by columnar diatomite structure is higher than that of discoid diatomite. The battery made of high purity diatomite with discoid diatom has serious attenuation after 40 cycles. It could only retain 1/10 of the initial capacity, while the attenuation of the battery prepared by cylindrical diatomite is much better. The reason was that the specific surface area of macro porous silicon was much smaller than that of mesoporous silicon and less lithium ions were consumed in the irreversible process of forming solid electrolyte membrane for the first time. It could also be known that an appropriate amount of impurities in porous silicon can effectively reduce the volume expansion of silicon during the battery charge and discharge. The main reason was that the impurities occupied the internal space to alleviate the volume expansion of silicon or the excess carbon was coated on the impurities. © 2022, The Authors. All rights reserved.

关键词： Lithium-ion batteries

Highly Deformable Ag2te1-Xsex-Based Thermoelectric Compounds

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Feng, Liping Guo, Anan Liu, Keke Bai, Hui Zhang, Qingjie Wu, Jinsong Su, Xianli Tang, Xinfeng Uher, Ctirad Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration Zone Xiangyang441000 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Nanostructure Research Center Wuhan University of Technology Wuhan430070 China Department of Physics University of Michigan Ann ArborMI48109 United States

Thermoelectric semiconductors are crucial for many critical applications, but are also universally fragile, which greatly limits the development of room temperature flexible thermoelectric devices. Herein, an extraordinary deformability at room temperature and high thermoelectric performance are simultaneously realized in wide composition of Ag2Te1-xSex (x = 0-0.2) compounds with monoclinic structure. An average compressive strain rate of 24% at room temperature is attained for the pristine Ag2Te compound. Moreover, a tensile strain rate of 43% is measured at room temperature using the in-situ transmission electron microscopy. First Principles calculations and in-situ transmission electron microscope tensile test results indicate that the Ag2Te compound is inclined to slip along the (-102) [010] plane under external forces due to a larger ratio between the cleavage energy (Ec) and the slip energy barrier. The slipping process generates high concentrations of dislocations, deformations, and amorphous structures, which together dissipate the externally applied load energy, yielding superior deformability. Meanwhile, the maximum dimensionless figure of merit ZT of 0.61 is obtained at 380 K. This study demonstrates that Ag2Te-based compounds are promising for the fabrication of flexible thermoelectric devices in applications, such as wearable, room temperature electronic gadgets. © 2023, The Authors. All rights reserved.

关键词： High resolution transmission electron microscopy

Bifunctional Electrocatalyst Junction Engineering: Cop Nanoparticles In-Situ Anchored on Co3(Si2o5)2(Oh)2 Nanosheets for Highly Efficient Water Splitting

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Mu, Yang Dong, Xueying Jing, Xuyang Pei, Xiaoyu Zhao, Yunfeng Kou, Zongkui Meng, Changgong Zhang, Yifu State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology Dalian116024 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China College of Environmental and Chemical Engineering Dalian University Dalian116622 China

The development of promising bifunctional water splitting electrocatalysts through precise design of composition and structure is a challenging topic. In this work, a novel junction is developed consisting of pure-phase CoP nanoparticles in-situ grown on Co3(Si2O5)2(OH)4 nanosheets, denoted as CoP/CSNSs. Rely on the small adding Co2+ in complex precursor, controllable synthesis of pure-phase CoP without impure phases is achieved, and the perfect nanosheet structure from support can be inherited, the CoP/CSNSs therefore shows the highest electrocatalytic performance for both HER and OER in 1.0 M KOH. Besides, the overall water splitting voltage of CoP/CSNSs(+/-) delivers 1.50 V at 10 mA cm-2, which outperforms that of the commercial Pt/C||RuO2 system. The preferable bifunctional electrocatalytic performance benefits from the optimized electron state of the adjacent dual-active centers, such that surficial CoP contributes to the dissociation of H-OH bonds boosting the Volmer step of HER, and Co3(Si2O5)2(OH)4 support contributes to OH- adsorption facilitating the kinetics of OER. Meanwhile, the advanced nanosheet structure provides more accessible active centers and more efficient charge/mass transport highway. In this work, bifunctional metal silicate electrocatalyst for water dissociation is designed and fabricated for the first time. The simple and effective phase-modulation and structure-control is a promising strategy for continually exploitation of multifunctional metal silicate electrocatalysts. Such low-cost and highly efficient electrocatalysts may create new opportunities for future development of renewable energy conversion technologies. © 2022, The Authors. All rights reserved.

关键词： Nanoparticles

Facile one-step vulcanization of copper foil towards stable Li metal anode

学校读者我要写书评

暂无评论

Science China materials 2020年第9期63卷 1663-1671页

作者： Danqi He Yaqi Liao Zexiao Cheng Xiahan Sang Lixia Yuan Zhen Li Yunhui Huang State Key Laboratory of Material Processing and Die and Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Lithium metal has been regarded as the ultimate anode for next-generation rechargeable batteries with high energy ***,its high reactivity and dendrite growth seriously limit its commercial application,which can be well addressed by realizing uniform Li ***,we report a facile and scalable one-step vulcanization method to modify commercial Cu foil with lithophilic *** in situ formed Cu2S layer can not only promote the homogeneous deposition of Li via its lithophilic nature,but also benefit the formation of a stable solid-electrolyte interphase during initial *** Cu2S-modified Cu current collector realizes dendrite-free Li plating/stripping and thus exhibits stable cycling performance with a high Coulombic efficiency,even with a large capacity of 4 mA h cm^-2.A full-cell consisting of a Cu2S/Cu-Li anode and a LiFePO4 cathode exhibits greatly improved cycling stability and enhanced Coulombic efficiency,demonstrating the effectiveness and practicability of the proposed Cu2S/Cu foil in the field of rechargeable Li metal batteries.

关键词： lithium metal anode current collector lithophilic layer copper sulfide electrochemical performance

Nanomultilayer Gradation Strategy to Improve Mechanical Properties of Tisin/Alcrn Hard Coatings

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Li, Qizhong Liu, Fazhen Yang, Mai Gao, Tenghua Ji, Baifeng Zhang, Song Tu, Rong Zhang, Lianmeng Chaozhou Branch of Chemistry and Chemical Engineering Guangdong Laboratory Chaozhou521000 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology 122 Luoshi Road Wuhan430070 China Wuhan University of Technology Advanced Engineering Technology Research Institute of Zhongshan City Xiangxing Road 6 Guangdong Zhongshan528400 China Hubei Technology Innovation Center for Advanced Composites Wuhan University of Technology 122 Luoshi Road Wuhan430070 China School of Civil Engineering and Architecture Wuhan University of Technology 122 Luoshi Road Wuhan430070 China Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of Technology Wuhan430070 China

The structures design and optimization of multilayer coatings, which are utilized to surmount the trade-off between hardness and toughness, has been a current hot topic in the field of hard ceramic coatings. Herein, multi-layered TiSiN/AlCrN coatings with a constant and gradient sublayer thickness (Λ, modulation periods) ranging from 20 to 3.8 nm were prepared by the Cathodic Arc Ion plating. The microstructure, mechanical properties, residual stress and fracture toughness of four gradient structures were investigated systematically. All coatings exhibit a typical FCC crystal structure. In the coating with a monotonous decrease of modulation period (G2 gradient structure), the interface between the TiSiN layer and the AlCrN layer transformed from a partially semi-coherent interface at the bottom layers of Λ = 20 nm, to a fully coherent interface at the top layers of Λ = 3.8 nm, showing the higher mechanical properties than those of G2 (reverse structure of G1). The coating with dual-gradient V2 structure (G1+G2) demonstrated the highest hardness (37.6 ± 1.0 GPa), H/E and H3/E2 ratios (0.095 and 0.34 GPa), and bonding strength (75.3 N), as well as lowest friction coefficient (0.34) and wear rate (6.7×10-6 mm3/Nm). The remarkable resistance to damage and toughness displayed by the V2 structure could be ascribed to its intrinsic capacity for effectively alleviating stress concentration and accommodating incompatibilities during the plastic deformation process. This work offers insights into employing gradient architecture design to enhance the strength and toughness of coatings. © 2024, The Authors. All rights reserved.

关键词： Silicon compounds

Study of the Effect of Impregnation on Continuous Carbon Fibers Reinforced Sic Ceramic Composites Prepared Via Material Extrusion and Reactive Melting Infiltration

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Liu, Kai Qiu, Lei Zhang, Yuzhen Du, Yanying Sun, Ce Lu, Chao Zhang, Song Tu, Rong Wu, Yanjiao Sun, Huajun Shi, Yusheng State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan430070 China School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China School of Logistics Engineering Wuhan University of Technology Wuhan430070 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Ningbo volken Technology Co. Ltd Ningbo315000 China State Key Laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology Wuhan430074 China

This paper presents a new method for the efficient preparation of continuous carbon fibers reinforced SiC ceramic (Cf/SiC) composites using material extrusion (MEX) and reactive melting infiltration (RMI). A slurry with the ability to produce stable filaments with good surface quality has been obtained by comparing the rheological behavior. The resin impregnation-carbonization and RMI processes were used for densification to obtain Cf/SiC composites. The effect of the number of impregnation-carbonization on the properties and microstructure of the sintered bodies has been studied. When the impregnation-carbonization was used for 1 time, the specific strength of the sintered body reached the highest value of 4.5 [[EQUATION]] 10 4 N·m/kg and the bending strength reached 93.1±4.3 MPa. In addition, Cf/SiC with complex structures were prepared using this method. This new approach reveals significant potential for MEX printing technology to prepare Cf/SiC composites with complex and lightweight structures. © 2022, The Authors. All rights reserved.

关键词： Carbon fibers

In Situ Programming Acid-Base Pair Proton-Conductive Channels of Perfluorosulfonic Acid Membrane for Fuel Cells

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Zhang, Wenxing Zhao, Shengqiu Wang, Rui Zhang, Aojie Huang, Yi Tang, Haolin State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen Valley Foshan528200 China State Key Laboratory of Automotive Safety and Energy School of vehicle and Mobility Tsinghua University Beijing100084 China

The development of rapid and dependable proton transport channels is crucial for proton exchange membrane fuel cells (PEMFCs) operating in low humidity conditions. Herein, an NH-Zr framework rich in basic sites was constructed in situ in a perfluorosulfonic acid solution, and PFSA-NH-Zr hybrid proton exchange membranes were prepared. The introduced NH-Zr framework successfully induced proton conducting groups (-SO3H) reorganization along the NH-Zr framework, resulting in the formation of fast ion transport channels. Meanwhile, under low humidity, the acid-base pairs between N-H (N-H-Zr framework) and -SO3H (PFSA) promoted the protonation/deprotonation and the subsequent proton leap via the Grotthuss processes. Especially, the hybrid membrane PFSA-NH-Zr-1 with suitable NH-Zr content had a promising proton conductivity of 0.031 S/cm at 80°C, 40% RH, and 0.292 S/cm at 80°C, 100% RH, which were approximately 33% and 40% higher than the pristine PFSA membrane (0.023 S/cm and 0.209 S/cm), respectively. In addition, the maximum power density of the hybrid PEM was 0.726 W/cm2, which was nearly 20% higher than the pristine PFSA membrane (0.604 W/cm2) under 80°C, 40% RH. This work established a referable strategy for developing high-performance proton exchange membranes under low RH conditions. © 2022, The Authors. All rights reserved.

关键词： Proton conductivity

Light-driven directional ion transport for enhanced osmotic energy harvesting

学校读者我要写书评

暂无评论

National Science Review 2021年第8期8卷 178-185页

作者： Kai Xiao Paolo Giusto Fengxiang Chen Ruotian Chen Tobias Heil Shaowen Cao Lu Chen Fengtao Fan Lei Jiang Max Planck Institute of Colloids and Interfaces Department of Colloid Chemistry Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang University State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile University State Key Laboratory of Catalysis 2011-iChEMDalian National Laboratory for Clean Energy (DNL)Dalian Institute of Chemical Physics(DICP)Chinese Academy of Sciences State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Light-driven ion（proton） transport is a crucial process both for photosynthesis of green plants and solar energy harvesting of some archaea. Here, we describe use of a TiO2/C3N4semiconductor heterojunction nanotube membrane to realize similar light-driven directional ion transport performance to that of biological systems. This heterojunction system can be fabricated by two simple deposition steps. Under unilateral illumination, the TiO2/C3N4heterojunction nanotube membrane can generate a photocurrent of about 9 μA/cm2, corresponding to a pumping stream of ～5500 ions per second per nanotube. By changing the position of TiO2and C3N4, a reverse equivalent ionic current can also be realized. Directional transport of photogenerated electrons and holes results in a transmembrane potential, which is the basis of the light-driven ion transport phenomenon. As a proof of concept, we also show that this system can be used for enhanced osmotic energy generation. The artificial light-driven ion transport system proposed here offers a further step forward on the roadmap for development of ionic photoelectric conversion and integration into other applications, for example water desalination.

关键词： ion pump ion transport nanofluidic porous membrane carbon nitride