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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi Yi wan Yongqiang zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Recent Advances in Mechanistic Understanding of Metal-Free Carbon Thermocatalysis and Electrocatalysis with Model Molecules

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Nano-Micro Letters 2024年第7期16卷 74-97页

作者： Wei Guo Linhui Yu Ling Tang Yan wan Yangming Lin CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021People’s Republic of China

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and *** the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction ***,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental *** this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon *** both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically *** with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular ***,the outlook of model carbon catalysis has also been proposed in this work.

关键词： Metal-free carbon catalysts Model catalyst Electrocatalysis Active site Reaction mechanisms

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Identification of the optimal doping position of hetero-atoms in chalcogen-doped Fe-N-C catalysts for oxygen reduction reaction

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Particuology 2024年第6期89卷 99-108页

作者： Weihao Liu Huanhuan He Qingtao Liu Xin wan Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing100191China School of Space and Environment Beihang UniversityBeijing102206China Tianmushan Laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,S,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)Se_(1)/NC and Fe–N_(3)Se_(1)/NC demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-C catalysts Hetero-atom doping Doping position Enhancement mechanism

Substrate screening for superclean graphene growth using firstprinciples calculations

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Nano Research 2024年第4期17卷 2216-2222页

作者： zhihao Li Xiucai Sun Xiaoli Sun wan-Jian Yin zhongfan Liu College of Energy Soochow Institute for Energy and Materials InnovationS(SIEMIS)and Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Graphene Basic Science Research Center Beijing Graphene Institute(BGI)Beijing 100095China Center for Nanochemistry Beijing Science and Engineering Center for NanocarbonsBeijing National Laboratory for Molecular ScienceCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Suppressing the formation of amorphous surface carbon and contaminants during the preparation of graphene by chemical vapor deposition remains an ongoing ***,we analyzed how substrate characteristics affect graphene quality by simulating margin extension,the nucleation process,and defect pegging configurations on mono-crystalline oriented metal substrates with the aim of enhancing graphene *** formation energy and nucleation potential,which are indirect substrate–graphene interaction features,were found to appropriately evaluate graphene *** crystallographic orientation of the metal substrate was discovered to be critical for producing superclean graphene.A low graphene defect density and high nucleation rate on the Cu(100)facet guarantee growth of high-quality graphene,especially in terms of suppressing the formation of amorphous *** addition,rapid kink growth and self-healing on the Cu(100)facet facilitate rapid graphene synthesis,which is also promoted by rapid kink splicing and margin self-repair on this *** study provides theoretical insight useful for the synthesis of superclean graphene.

关键词： superclean graphene defects nucleation metal substrates density functional theory calculations

Highly efficient recovery of waste LiNi_(x)Co_(y)Mn_(z)O_(2) cathode materials using a process involving pyrometallurgy and hydrometallurgy

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 149-160页

作者： Tianwei zhang Juanye Dao Jinsong wang Yuzhong Guo Rundong wan Chengping Li Xian zhou zhengfu zhang Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Substantial environmental and economic benefits can be achieved by recycling used lithium-ion batteries. Hydrometallurgy is often employed to recover waste LiNi_(x)Co_(y)Mn_(z)O_(2) cathode materials. As Ni, Co and Mn are transition metals, they exhibit similar properties;therefore, separating them is difficult. Thus, most researchers have focused on leaching processes, while minimal attention has been devoted to the separation of valuable metals from waste LiNi_(x)Co_(y)Mn_(z)O_(2) cathode materials. Herein, we propose an environment-friendly, gentle process involving the usage of pyrometallurgy and hydrometallurgy to gradually leach valuable metals and effectively separate them. Interestingly, Li is recovered through a reduction roasting and water leaching process using natural graphite powder, Ni and Co are recovered through ammonia leaching and extraction processes and Mn is recovered through acid leaching and evaporation–crystallization processes. Results show that ~87% Li, 97.01% Co, 97.08% Ni and 99% Mn can be leached using water, ammonia and acid leaching processes. The result obtained using the response surface methodology shows that the concentration of (NH4)2SO3 is a notable factor affecting the leaching of transition metals. Under optimal conditions, ~97.01% Co, 97.08% Ni and 0.64% Mn can be leached out. The decomposition of LiNi_(x)Co_(y)Mn_(z)O_(2) is a two-step process. This study provides valuable insights to develop an environment-friendly, gentle leaching process for efficiently recycling valuable metals, which is vital for the lithium-ion battery recycling industry.

关键词： Waste LiNixCoyMnzO2 cathode materials Leaching Effective separation Series process

Nonlinear optics of two-dimensional heterostructures

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Frontiers of physics 2024年第3期19卷 19-27页

作者： Xiangkun zeng Chenyu wan zhichen zhao Di Huang zhanshan wang Xinbin Cheng Tao Jiang MOE Key Laboratory of Advanced Micro-Structured Materials Shanghai Frontiers Science Center of Digital OpticsInstitute of Precision Optical Engineeringand School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 200092China

Two-dimensional (2D) materials exhibit exceptionally strong nonlinear optical responses, benefiting from their reduced dimensionality, relaxed phase-matching requirements, and enhanced light-matter interaction. With additional degrees of freedom in the modulation of the physical properties by stacking 2D layers together, nonlinear optics of 2D heterostructures becomes increasingly fascinating. In this perspective, we provide a brief overview of recent advances in the field of nonlinear optics of 2D heterostructures, with a particular focus on their remarkable capabilities in characterization and modulation. Given the recent advances and the emergence of novel heterostructures, combined with innovative tuning knobs and advanced nonlinear optical techniques, we anticipate deeper insights into the underlying mechanisms and more associated applications in this rapidly evolving field.

关键词： nonlinear optics 2D heterostructures

Critical role of carbon support in metal nanoaggregate facilitating Fe-N-C catalyst for PEM fuel cell application

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Journal of Energy Chemistry 2024年第10期97卷 669-676页

作者： Liming Guo Xin wan Qingtao Liu Xiaofang Liu Jiaxiang Shang Ronghai Yu Jianglan Shui School of Materials Science and Engineering Beihang University Tianmushan Laboratory

Metal nanoaggregates can simultaneously enhance the activity and stability of Fe-N-C catalysts in proton-exchange-membrane fuel cells（PEMFC）.Previous studies on the relevant mechanism have focused on the direct interaction between FeN4active sites and metal ***,the role of carbon support that hosts metal nanoaggregates and active sites has been ***,a Fe-N-C catalyst encapsulating inactive gold nanoparticles is prepared as a model catalyst to investigate the electronic tuning of Au nanoparticles（NPs） towards the carbon *** NPs donate electrons to carbon support,making it rich in π electrons,which reduces the work function and regulates the electronic configuration of the FeN4sites for an enhanced ORR ***,the electron-rich carbon support can mitigate the electron depletion of FeN4sites caused by carbon support oxidation,thereby preserving its high *** yield and accumulation of H2O2are thus alleviated,which delays the oxidation of the catalyst and benefits the *** to the electron-rich carbon support,the composite catalyst achieves a top-level peak power density of 0.74 W/cm2in a 1.5 bar H2-air PEMFC,as well as the improved *** work elucidates the key role of carbon support in the performance enhancement of the FeN-C/metal nanoaggregate composite catalysts for fuel cell application.

关键词： Carbon support Fe-N-C Fuel cells Hetero-structure catalyst Oxygen reduction reaction

Genetic analysis and fine mapping of a grain size QTL in the smallgrain sterile rice line zhuo201S

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Journal of Integrative Agriculture 2024年第7期23卷 2155-2163页

作者： Bin Lei Jiale Shao Feng zhang Jian wang Yunhua Xiao zhijun Cheng Wenbang Tang Jianmin wan College of Agronomy Hunan Agricultural UniversityChangsha 410128China National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory for Crop Genetics and Germplasm Enhancement/Jiangsu Plant Gene Engineering Research Center Nanjing Agricultural UniversityNanjing 210095China State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research CenterChangsha 410125China

The development and application of the small-grain rice sterile line zhuo201S(z201S)has demonstrated its potential for mechanized hybrid rice seed production,leading to significant cost ***,the molecular mechanism responsible for the small-grain size characteristic of z201S remains *** this study,we conducted a genetic analysis using near-isogenic lines constructed from z210S,a small-grain rice sterile line,and R2115,a normal-grain *** results revealed that the small-grain trait in z201S is governed by a single partially dominant gene which also enhances grain *** mapping,we localized the causal gene to the short arm of chromosome 2,within a 113 kb physical region delimited by the molecular markers S2-4-1 and *** analysis and gene expression assays indicated LOC_Os02g14760 as the most likely candidate gene,suggesting that the small-grain size trait of z201S is controlled by a novel locus that has not been previously identified.

关键词： rice grain size map-based cloning

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Wearable pressure sensors based on antibacterial and porous chitosan hydrogels for full-range human motion detection

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Science China Technological Sciences 2024年第8期67卷 2475-2484页

作者： zHANG YingXin LIU HanGuang JIN ShunYu LI YaJuan zHANG wan zHOU Hang NIE zanXiang HUANG Yuan School of Microelectronics Science and Technology Sun Yat-sen University Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Department of Clinical Laboratory the First Affiliated Hospital of Anhui Medical University School of Electronic and Computer Engineering Peking University Shenzhen Graduate School zinergy Shenzhen Ltd.

Wearable pressure sensors made from conductive hydrogels hold significant potential in health monitoring. However, limited pressure range（Pa to hundreds of kPa） and inadequate antibacterial properties restrict their practical applications in diagnostic and health evaluation. Herein, a wearable high-performance pressure sensor was assembled using a facilely prepared porous chitosan-based hydrogel, which was constructed from commercial phenolphthalein particles as a sacrificial template. The relationship between the porosity of hydrogels and sensing performance of sensors was systematically explored. Herein, the wearable pressure sensor, featuring an optimized porosity of hydrogels, exhibits an ultrawide sensing capacity from 4.83 Pa to 250 k Pa（range-to-limit ratio of 51,760） and high sensitivity throughout high pressure ranges(0.7 kPa-1, 120–250 kPa). The presence of chitosan endows these hydrogels with outstanding antibacterial performance against E. coli and S. aureus, making them ideal candidates for use in wearable electronics. These features allow for a practical approach to monitor full-range human motion using a single device with a simple structure.

关键词： porous hydrogels antibacterial performances wearable pressure sensors full-range human motion chitosan

Giant piezotronic effect in ferroelectric field effect transistor

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Nano Research 2024年第9期17卷 8465-8471页

作者： Haiming zhang Mengshuang Chi Shidai Tian Tian Liang Jitao Liu Xiang zhang Lingyu wan zhong Lin wang Junyi zhai Center on Nanoenergy Research School of Physical Science&TechnologyGuangxi UniversityNanning 530004China Beijing Key Laboratory of Micro-Nano Energy and Sensor Center for High-Entropy Energy and SystemsBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of ScienceBeijing 100049China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Georgia Institute of Technology AtlantaGA 30332USA

The piezotronics effect utilizes a piezopotential to modulate and control current in *** materials,as a type of piezoelectric materials,possess piezoelectric coefficients that are significantly larger than those found in conventional piezoelectric ***,we propose a strain modulated ferroelectric field-effect transistor(St-FeFET)utilizing external strain instead of gate voltage to achieve ferroelectric modulation,which eliminates the need for gate *** applying a very small strain(0.01%),the St-FeFET can achieve a maximum on-off current ratio of 1250%and realizes a gauge factor(GF)of 1.19×10^(6),which is much higher than that of conventional strain *** work proposes a new method for realizing highly sensitive strain sensors and presents innovative approaches to the operation methods of ferroelectric field-effect transistors as well as potential applications for coupling of strain sensors and various devices across different fields.

关键词： ferroelectric field-effect transistors piezotronics [Pb(Mg1/3Nb2/3)O3](1-x)-[PbTiO3]x(PMN-PT) strain sensors