检索结果-内蒙古大学图书馆

Enhanced N_(2)electroreduction activity of single-atom catalysts:Modulating the linear scaling relationship by coordination engineering and dual-site strategies

引用

Nano Research 2025年第3期18卷 696-709页

作者： Renyi Li Caimu Wang Jiao Zhang Wei Guo Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of TechnologyBeijing 100081China Frontiers Science Center for High Energy Material(MOE) Beijing Institute of TechnologyBeijing 100081China

The volcano plot is widely used to elucidate the activity trends among different catalysts,thereby effectively screening and guiding catalyst ***,the inherent linear scaling relationship(LSR)constrains the breakthrough in the activity of catalysts,and the understanding of the activity limit in volcano plot is still *** this work,by employing first-principles calculations and microkinetic modeling,we proposed coordination engineering(CE)and dual-site(DS)strategies to surpass the Sabatier’s limitation of WS_(2)-supported TM(TM@WS_(2))single-atom catalysts(SACs)for electrocatalytic nitrogen reduction reaction(eNRR).We found that the LSR betweenΔG(^(*)N_(2)→^(*)N_(2)H)andΔG(^(*)NH_(2)→^(*)NH_(3))was optimized to be closer to the ideal space of eNRR activity after modulating TM@WS_(2)SACs by these two design *** combining the reaction selectivity trend plot,we picked out N-Os@WS_(2),C-Ir@WS_(2),Fe_(2)@WS_(2),and Ru_(2)@WS_(2)as optimal eNRR catalysts with low limiting potential(UL),and N-Os@WS_(2)SAC(UL:-0.28 V)outperforms the best eNRR catalyst among TM@WS_(2)*** constructing explicit solvent models,we conducted a detailed study on the reaction kinetics of proton transfer over these four *** propose that the activity enhancement in TM@WS_(2)SACs for eNRR can be attributed to the ligand effect and geometric effect brought about by CE and DS strategies,improving the donation-backdonation process of electron transfer between N_(2)and the active *** designed catalyst has certain resistance to demetallization and agglomeration under simulated solvent *** work provides a feasible design strategy for the activity enhancement of SACs and brings a new perspective to deeply understanding the volcano plot in heterogeneous catalysis.

关键词： linear scaling relationship volcano plot single-atom catalysts density functional theory(DFT) electrochemical nitrogen reduction

来源：评论

学校读者我要写书评

暂无评论

Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

引用

Rare Metals 2024年第4期43卷 1635-1646页

作者： Yong-Nian Ma Ling-Chen Kong Shao-Shan Chen Yong Wang Li-Dong Sun Cong Peng Meng-Meng Qin Yu Li Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300072China Institute of Advanced Technology and Equipment Beijing University of Chemical TechnologyBeijing100029China

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active ***,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage ***,the continuous capacity decay during cycles has hindered the widespread application of these cathode *** fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(Li_(1.6)Mn_(1.6)O_(3.7)F_(0.3,)LMOF1.6)was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical *** inorganic fluorinated layer,mainly containing LiF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation *** LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mAh·g^(-1)at 50 mA·g^(-1)and an enhanced capacity retention of 29.6%after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9%capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability

来源：评论

学校读者我要写书评

暂无评论

Recent progress in single-atom nanozymes research

引用

Nano Research 2023年第2期16卷 1878-1889页

作者： Bing Jiang Zhanjun Guo Minmin Liang Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China

Single-atom nanozyme(SAzyme)is the hot topic of the current nanozyme *** intrinsic properties,such as high activity,stability,and low cost,present great substitutes to natural ***,its fundamental characteristics,i.e.,maximized atom utilizations and well-defined geometric and electronic structures,lead to higher catalytic activities and specificity than traditional *** have been applied in many biomedical areas,such as anti-tumor therapy,biosensing,antibiosis,and anti-oxidation ***,we will discuss a series of representative examples of SAzymes categorized by their biomedical applications in this *** the end,we will address the future opportunities and challenges SAzymes facing in their designs and applications.

关键词： single-atom nanozymes natural enzymes enzyme-like activity biomedical applications

来源：评论

学校读者我要写书评

暂无评论

FedDAA:a robust federated learning framework to protect privacy and defend against adversarial attack

引用

Frontiers of Computer science 2024年第2期18卷 107-122页

作者： Shiwei LU Ruihu LI Wenbin LIU Fundamentals Department Air Force Engineering UniversityXi’an 710051China Institute of Advanced Computational Science and Technology Guangzhou UniversityGuangzhou 510006China

Federated learning(FL)has emerged to break data-silo and protect clients’privacy in the field of artificial ***,deep leakage from gradient(DLG)attack can fully reconstruct clients’data from the submitted gradient,which threatens the fundamental privacy of *** cryptology and differential privacy prevent privacy leakage from gradient,they bring negative effect on communication overhead or model ***,the original distribution of local gradient has been changed in these schemes,which makes it difficult to defend against adversarial *** this paper,we propose a novel federated learning framework with model decomposition,aggregation and assembling(FedDAA),along with a training algorithm,to train federated model,where local gradient is decomposed into multiple blocks and sent to different proxy servers to complete *** bring better privacy protection performance to FedDAA,an indicator is designed based on image structural similarity to measure privacy leakage under DLG attack and an optimization method is given to protect privacy with the least proxy *** addition,we give defense schemes against adversarial attack in FedDAA and design an algorithm to verify the correctness of aggregated *** results demonstrate that FedDAA can reduce the structural similarity between the reconstructed image and the original image to 0.014 and remain model convergence accuracy as 0.952,thus having the best privacy protection performance and model training *** importantly,defense schemes against adversarial attack are compatible with privacy protection in FedDAA and the defense effects are not weaker than those in the traditional ***,verification algorithm of aggregation results brings about negligible overhead to FedDAA.

关键词： federated learning privacy protection adversarial attacks aggregated rule correctness verification

来源：评论

学校读者我要写书评

暂无评论

Superior QLC Retention (10 years, 85°C) and Record Memory Window (12.2 V) by Gate Stack Engineering in Ferroelectric FET: from "MIFIS" to "MIKFIS"

Superior QLC Retention (10 years, 85°C) and Record Memory W...

引用

2024 IEEE International Electron Devices Meeting, IEDM 2024

作者： Kuk, Song-Hyeon Kim, Bong Ho Park, Youngkeun Ko, Kyul Hwang, Hyeon-Seong Lee, Dahye Cho, Byung Jin Han, Jae-Hoon Kim, Sang-Hyeon School of Electrical Engineering Korea Advanced Institute of Science and Technology Daejeon Korea Republic of Graduate School of Semiconductor Technology Korea Advanced Institute of Science and Technology Daejeon Korea Republic of Korea Institute of Science and Technology Seoul Korea Republic of

ISBN: (纸本)9798350365429

As stacking hundreds of layers, 3D NAND faces new challenges and needs for further scaling. Ferroelectric field-effect-transistor (FEFET) is a potential solution, with advancements in gate stack engineering, specifically the metal-insulator-ferroelectric-insulator-semiconductor (MIFIS) stack, achieving a memory window (MW) over 10 V. However, the gate stack with a feasible MW is still thicker (>18 nm) than that of charge-trap-flash (CTF) NAND, degrading bit density. Additional MW expansion methods using bandgap engineering (BE) with an oxide-nitride-oxide (ONO) layer were also proposed, but further increased the gate stack thickness. Moreover, the previous approaches have critical drawbacks such as monoclinic-(m-) phases in thick FE-HfO2 films, unstable retention, degraded write voltage and speed, and higher equivalent oxide thickness (EOT). To address the issues, we propose a novel gate stack, metal-insulator-high k-ferroelectric-insulator-semiconductor (MIKFIS). The main idea is that the FE-HfO2 thickness can be scaled down by partially replacing it with paraelectric (PE) HfO2, without increasing the gate stack thickness. In addition, fabricated MIKFIS FEFETs show a record MW of 12.2 V with the Si channel, highly reliable 10-year retention with quad-level-cell (QLC) operations at 24ºC and 85ºC for the first time. The origin of the stable retention is revealed by accurately measuring absolute polarization (P) directly from the FEFETs. The superiority of the MIKFIS FEFET indicates that a MIKFIS stack is a strong candidate for the gate stack in 3D FE NAND. © 2024 IEEE.

关键词： Metal insulator boundaries

来源：评论

学校读者我要写书评

暂无评论

Overcoming side reaction effects in the colloidal synthesis of ZnSe/ZnS core/shell quantum dots with an etching strategy

引用

Nano Research 2024年第8期17卷 7020-7026页

作者： Jinhua He Chenhui Wang Mingrui Liu Muhammad Ramzan Zhiwei Long Xian-gang Wu Yu Chen Haizheng Zhong MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Engineering Research Center for Mixed Reality and Advanced Display Technology School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China

The potential use of large-size ZnSe quantum dots as blue emitters for display applications has greatly inspired the colloidal ***,we report the negative effects of side reactions of large-size ZnSe quantum *** side reactions between oleic acid and oleylamine generated amidation products and H_(2)O,which led to the hydrolysis of Zn(OA)2 to Zn(OH)2 and the subsequent formation of zinc oxide(ZnO)and zinc bis[diphenylphosphinate](Zn(DPPA)2)*** side reactions resulted in the formation of a defective surface including a Se-rich surface and oxygen-related *** negative effects can be overcome by adopting an etching strategy using potassium fluoride and myristic acid in *** overcoating a ZnS shell,blue emissive ZnSe/ZnS quantum dots with a maximum photoluminescence quantum yield of up to 91%were *** further fabricated ZnSe quantum dots-based blue light-emitting diodes with an emission peak at 456 *** device showed a turn-on voltage of 2.7 V with a maximum external quantum efficiency of 4.2%and a maximum luminance of 1223 cd·m^(−2).

关键词： quantum dots ZnSe side reactions surface etching light-emitting diodes

来源：评论

学校读者我要写书评

暂无评论

Realizing n-type CdSb with promising thermoelectric performance

引用

Journal of Materials science & technology 2023年第13期144卷 54-61页

作者： Peng Zhao Honghao Yao Shizhen Zhi Xiaojing Ma Zuoxu Wu Yijie Liu Xinyu Wang Li Yin Zongwei Zhang Shuaihang Hou Xiaodong Wang Siliang Chen Chen Chen Xi Lin Haoliang Liu Xingjun Liu Feng Cao Qian Zhang Jun Mao School of Materials Science and Engineering and Institute of Materials Genome&Big DataHarbin Institute of Technology(Shenzhen)Shenzhen 518055China School of Science Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Realizing high performance in both n-type and p-type materials is essential for designing efficient ther-moelectric ***,the doping bottleneck is often encountered,i.e.,only one type of conduction can be *** one example,p-type CdSb with high thermoelectric performance has been discovered for several decades,while its n-type counterpart has rarely been *** this work,the calculated band structure of CdSb demonstrates that the valley degeneracy is as large as ten for the conduction band,and it is only two for the valence ***,the n-type CdSb can potentially realize an ex-ceptional thermoelectric ***,the n-type conduction has been successfully real-ized by tuning the stoichiometry of *** further doping indium at the Cd site,an improved room-temperature electron concentration has been *** modeling predicts an optimal electron con-centration of∼2.0×1019 cm−3,which is higher than the current experimental ***,future optimization of the n-type CdSb should mainly focus on identifying practical approaches to optimize the electron concentration.

关键词： Thermoelectric materials n-type CdSb Indium doping Band degeneracy

来源：评论

学校读者我要写书评

暂无评论

Latest advances in ionic liquids promoted synthesis and application of advanced biomass materials

引用

Frontiers of Chemical science and Engineering 2023年第7期17卷 798-816页

作者： Ting He Jipeng Yan Wenzhe Xiao Jian Sun Key Laboratory of Molecular Medicine and Biotherapy in the Ministry of Industry and Information Technology School of Life ScienceBeijing Institute of TechnologyBeijing 100081China Beijing Engineering Research Center of Cellulose and Its Derivatives Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing 100081China

The utilization of sustainable resources provides a path to relieving the problem of dependence on fossil resources. In this context, biomass materials have become a feasible substitute for petroleum-based materials. The development of biomass materials is booming and advanced biomass materials with various functional properties are used in many fields including medicine, electrochemistry, and environmental science. In recent years, ionic liquids have been widely used in biomass pretreatments and processing owing to their “green” characteristics and adjustable physicochemical properties. Thus, the effects of ionic liquids in biomass materials generation require further study. This review summarizes the multiple roles of ionic liquids in promoting the synthesis and application of advanced biomass materials as solvents, structural components, and modifiers. Finally, a prospective approach is proposed for producing additional higher-quality possibilities between ionic liquids and advanced biomass materials.

关键词： biomass materials functional materials ionic liquids synthesis structure-property relationship

来源：评论

学校读者我要写书评

暂无评论

Edge effect during microwave plasma chemical vapor deposition diamond-film:Multiphysics simulation and experimental verification

引用

International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2287-2299页

作者： Zhiliang Yang Kang An Yuchen Liu Zhijian Guo Siwu Shao Jinlong Liu Junjun Wei Liangxian Chen Lishu Wu Chengming Li Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China National Key Laboratory of Solid-State Microwave Devices and Circuits The 55th Research Institute of China Electronics Technology Group CorporationNanjing 210016China

This study focused on the investigation of the edge effect of diamond films deposited by microwave plasma chemical vapor *** bulge height△h is a factor that affects the edge effect,and it was used to simulate plasma and guide the diamond-film deposition ***-element software COMSOL Multiphysics was used to construct a multiphysics(electromagnetic,plasma,and fluid heat transfer fields)coupling model based on electron collision *** spectroscopy and scanning electron microscopy were performed to characterize the experimental growth and validate the *** simulation results reflected the experimental trends *** discharge at the edge of the substrate accelerated due to the increase in△h(△h=0-3 mm),and the values of electron density(n_(c)),molar concentration of H(C_(H)),and molar concentration of CH_(3)(C_(CH_(3)))doubled at the edge(for the special concave sample with△h=−1 mm,the active chemical groups exhibited a decreased molar concentration at the edge of the substrate).At=0-3 mm,a high diamond growth rate and a large diamond grain size were observed at the edge of the substrate,and their values increased *** uniformity of film thickness decreased *** Raman spectra of all samples revealed the first-order characteristic peak of dia-mond near 1332 cm^(−1).When△h=−1 mm,tensile stress occurred in all regions of the ***△h=1-3 mm,all areas in the film ex-hibited compressive stress.

关键词： microwave plasma chemical vapor deposition edge discharge plasma diamond film

来源：评论

学校读者我要写书评

暂无评论

Highly stabilized and selective ammonia electro-oxidation over CuNi metallic glass nanoarray

引用

Carbon Energy 2025年第2期7卷 131-143页

作者： Yunrui Tian Rui Chen Xiaoqing Liu Zixian Mao Haotian Tan De'an Yang Feng Hou Xiaoguang Liu Lichang Yin Xiao Yan Ji Liang Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education School of Materials Science and Engineering Tianjin UniversityTianjinChina Shenzhen Institute of Information Technology ShenzhenGuangdongChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyangLiaoningChina

Electrochemical nitrogen looping represents a promising carbon-free and sustainable solution for the energy transition,in which electrochemical ammonia oxidation stays at the central ***,the various nitrogen-containing intermediates tend to poison and corrode the electrocatalysts,even the state-of-the-art noble-metal ones,which is worsened at a high applied ***,we present an ultrarapid laser quenching strategy for constructing a corrosion-resistant and nanostructured CuNi alloy metallic glass *** this material,single-atom Cu species are firmly bonded with the surrounding Ni atoms,endowing exceptional resistance against ammonia corrosion relative of conventional CuNi ***,a record-high durability for over 300 h is *** quenching also allows a much higher Cu content than typical single-atom alloys,simultaneously yielding a high rate and selectivity for ammonia oxidation reaction(AOR).Consequently,an outstanding ammonia conversion rate of up to 95%is achieved with 91.8%selectivity toward nitrite after 8 *** simulations reveal that the structural amorphization of CuNi alloy could effectively modify the electronic configuration and reaction pathway,generating stable singleatom Cu active sites with low kinetic barriers for *** ultrarapid laser quenching strategy thus provides a new avenue for constructing metallic glasses with well-defined nanostructures,presenting feasible opportunities for performance enhancement for AOR and other electrocatalytic processes.

关键词： ammonia oxidation reaction CuNi laser quenching metallic glasses

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：