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Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek Jr. Yang Yu Center for Supramolecular chemistry&Catalysis and department of chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and department of chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

p-d Orbital Hybridization Engineered Single-Atom Catalyst for Electrocatalytic Ammonia Synthesis

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Energy & Environmental Materials 2024年第2期7卷 119-125页

作者： Jingkun Yu Xue Yong Siyu Lu green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China department of chemistry University of SheffieldSheffieldS37HFUK

The rational design of metal single-atom catalysts(SACs)for electrochemical nitrogen reduction reaction(NRR)is ***-dimensional metal-organic frameworks(2DMOFs)is a unique class of promising *** to now,the roles of individual metals,coordination atoms,and their synergy effect on the electroanalytic performance remain ***,in this work,a series of 2DMOFs with different metals and coordinating atoms are systematically investigated as electrocatalysts for ammonia synthesis using density functional theory *** a specific metal,a proper metal-intermediate atoms p-d orbital hybridization interaction strength is found to be a key indicator for their NRR catalytic *** hybridization interaction strength can be quantitatively described with the p-/d-band center energy difference(Δd-p),which is found to be a sufficient descriptor for both the p-d hybridization strength and the NRR *** maximum free energy change(Δg_(max))andΔd-p have a volcanic relationship with OsC_(4)(Se)_(4)located at the apex of the volcanic curve,showing the best NRR *** asymmetrical coordination environment could regulate the band structure subtly in terms of band overlap and *** work may shed new light on the application of orbital engineering in electrocatalytic NRR activity and especially promotes the rational design for SACs.

关键词： first-principle calculations Nitrogen reduction p-d orbital hybridization single-atom catalysts

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu Min-Rui gao Division of Nanomaterials&chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

photochemical reactions as synthetic tool for pharmaceutical industries

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Chinese Chemical Letters 2024年第9期35卷 9-31页

作者： Shehla Khalid Muhammad Bilal Nasir Rasool Muhammad Imran department of chemistry Government College UniversityFaisalabad 38000Pakistan School of chemistry and Chemical Engineering Shandong UniversityJi’nan 250100China department of chemistry Faculty of ScienceKing Khalid UniversityAbha 61413Saudi Arabia

In the quest for new agrochemicals and pharmaceuticals,chemists seek access to reliable and mild synthetic techniques to allow for the systematic modification of chemical structures,exploration of unexplored chemical space,and facilitation of practical synthesis in their search for novel agrochemicals and *** this regard,photocatalytic reactions enabled the synthesis of intricate and more functionalized *** review overviews the developed synthetic methodologies and their utility in the chemical synthesis of *** review also offers in-depth insights into contemporary photoredox reactions such as allylic additions,cyclization,reductive cross-coupling,C–H activation,ring opening,oxidative cross-coupling,dehydrogenation,desulphonation,and *** provides a positive outlook for the promising future of this field.

关键词： photocatalyst photochemical reactions Drugs Natural products Late-stage functionalization

Molecular solid solution of lanthanide-titanium-oxo clusters with enhanced photocatalytic hydrogen evolution

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Science China chemistry 2024年第2期67卷 529-535页

作者： Rong Chen Chao-Long Chen Hui Zhang Zi-Han Wang Fu-Li Sun Ming-Hao Du gui-Lin Zhuang Cheng Wang La-Sheng Long Lan-Sun Zheng Xiang-Jian Kong Collaborative Innovation Centre of chemistry for Energy Materials State Key Laboratory of physical chemistry of Solid Surfaces and department of chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China College of Chemical Engineering Zhejiang University of TechnologyHangzhou310032China

Molecular solid solutions of metal clusters containing different metal centers with well-defined structures can accurately regulate the HOMO-LUMO gap,but are rarely ***,a series of colorless lanthanide-titanium-oxo clusters Ln_(2)Ti_4(μ_(2)-O)_(2)(μ_(3)-O)_4(piv)_(10)(THF)_(2)(Ln_(2)Ti_4,Ln = Eu,gd,Tb,and Ce,Hpiv = pivalic acid) were synthesized by the reaction of pivalic acid with Ln(Ac)_(3) and titanium *** light yellow crystal of cluster solid solutions Eu_(2)Ti_(4-x)Cd_(x),containing a mixture of Eu_(2)Ti_4 and Eu_(2)Ti_(3)Cd,was obtained by in situ doping Cd^(2+) and S^(2–).Eu_(2)Ti_(3.92)Cd_(0.08) displays efficient photocatalytic hydrogen evolution activity without a co-catalyst,which is up to 2.6 times that of Eu_(2)Ti_*** time-resolved transient absorption spectroscopy and spin-polarized density functional calculations showed that the enhanced photocatalytic performance of Eu_(2)Ti_(4-x)Cd_(x) can be attributed to the narrower HOMO-LUMO gap and lower LUMO position than that of Eu_(2)Ti_*** studyprovides an in situ doping method to realize the simple preparation of cluster solid solution.

关键词： molecular solid solution lanthanide-titanium-oxo clusters photocatalytic hydrogen evolution

Americium/lanthanide separation enabled by a distinct polyoxometalate cluster

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Science China chemistry 2024年第1期67卷 312-313页

作者： Hui Yang Xiangke Wang Shengqian Ma College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206P.R.China department of chemistry University of North TexasDentonTexas 76201United States

Nuclear energy is viewed as a low carbon-emission electricity-generating technology with high-energy density,which has attracted extensive attention and shown broad development prospects[1].However,to ensure sustainability and cleanability in the development of nuclear energy,one crucial challenge is to exploit efficient and economical technologies to simultaneously recover fissionable nuclides from nuclear waste and separate long-lived toxic fission products[2].

关键词： lanthanide separation cluster

Afterglow Nanoprobes for In-vitro Background-free Biomarker Analysis

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Chemical Research in Chinese Universities 2024年第2期40卷 213-224页

作者： ZHENg Ting WANg Ying LI Xianming LI Chenghui WU peng Analytical&Testing Centre State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu610064P.R.China School of chemistry and Chemical Engineering Henan Normal UniversityXinxiang453007P.R.China department of Rheumatology and Immunology West China HospitalSichuan UniversityChengdu610064P.R.China

Accurate detection of biomarkers is essential for disease *** the highly sensitive fluorescence probes are feasible for the above goal,it is typically interfered by the auto-fluorescence and light scattering of the biological *** afterglow system(consisting of photosensitizer,afterglow substrate and emitter)based on cascade photochemical reactions exhibits long-lived luminescence(seconds to hours),thus avoiding background *** the assistance of polymers,such as polystyrene microspheres,the photochemical afterglow systems have been transformed into homogeneous and water-soluble nanoparticles,and used for in-vitro biomarker ***,we summarized the principle,preparation and applications of these afterglow nanoparticles,and evaluated their performance in clinical sample testing by comparing with other nanoparticle-based ***,several problems and possible solutions of afterglow nanoparticle-based methods in biomarker determination were also mentioned.

关键词： photochemical afterglow In-vitro analysis Background-free detection Biomarker

Electrochemical Analysis of Single glucose Oxidase with a Nanopipette

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Chemical Research in Chinese Universities 2024年第2期40卷 272-278页

作者： WANg Yongyong MA Hui LONg Yi-Tao YINg Yi-Lun School of chemistry and Chemical Engineering Molecular Sensing and Imaging Center(MSIC)Nanjing UniversityNanjing210023P.R.China

Nanopore-based electrochemical technique is a promising tool for detecting single ***,detecting single proteins using a nanopipette in their native state without labeling is challenging due to the rapid translocation,which results in an inefficient signal *** our study,we finely tuned the driving force equilibrium between electrophoretic force(EpF)and electroosmotic flow(EOF)inside the nanopipette for efficient sensing of single glucose oxidase(gOD)*** duration time of gOD within the nanopipette is extended to about 4 *** strategy provided clear ionic current signals with a signal-to-noise ratio of *** EpF increased in the direction opposite to the motion of gOD,we observed a nonlinear growth in gOD’s duration *** extended the duration to about 4.4 times longer at−1000 mV compared to at−800 ***,nanopore-based electrochemical sensing could be used for single gOD molecule analysis as an ultrasensitive method.

关键词： Nanopore Single-molecule analysis glucose oxidase Electrophoretic force Electroosmotic flow

Single-atom pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.J.Kucernak David Zitoun department of chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael department of chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts