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Magnetic Resonance Letters 2024年第2期4卷 46-53页

作者： Xiaoli Xia Lei Zhu Weiping Tang luming peng Junchao Chen School of Chemistry and Chemical Engineering Shanghai Jiao Tong University800 Dongchuan RoadShanghai200240China Key Laboratory of Mesoscopic Chemistry of Ministry of Education and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing University163 Xianlin RoadNanjing210023China State Key Laboratory of Space Power-Sources Technology Shanghai Institute of Space Power-SourcesShanghai200245China

Recent advances in utilizing ^(17)O isotopic labeling methods for solid-state nuclear magnetic resonance(NMR)investigations of metal oxides for lithium-ion batteries have yielded extensive insights into their structural and dynamic details.Herein,we commence with a brief introduction to recent research on lithium-ion battery oxide materials studied using ^(17)O solid-state NMR spectroscopy.Then we delve into a review of ^(17)O isotopic labeling methods for tagging oxygen sites in both the bulk and surfaces of metal oxides.At last,the unresolved problems and the future research directions for advancing the ^(17)O labeling technique are discussed.

关键词： ^(17)O solid-state NMR ^(17)O isotopic labeling methods Bulk and surfaces of metal oxides DFT calculation

A green route for the preparation of layered double hydroxides from basic magnesium carbonate

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Magnetic Resonance Letters 2022年第3期2卷 177-185页

作者： Li Jin Xiaoyuan Zhou Juan Wen luming peng Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China Jiangsu Key Laboratory of Vehicle Emissions Control Nanjing UniversityNanjing210093China Frontiers Science Center for Critical Earth Material Cycling(FSC-CEMaC) Nanjing UniversityNanjing210023China

Layered double hydroxides(LDHs)have received extensive attention in many fields such as catalysis,environmental management and medical applications.Typically,expensive soluble metal salts are commonly used as the starting materials for the synthesis of LDHs.Here,we report a novel synthesis route for Mg/Al-LDH by using inexpensive basic magnesium carbonate as the starting material.X-ray diffraction(XRD)and solid-state nuclear magnetic resonance(ssNMR)data show that LDHs with rich defects are formed rapidly at room temperature and good crystallinity can be obtained after further hydrothermal treatment.These results provide a simple,rapid and green preparation method for LDHs.

关键词： Layered double hydroxides Green synthesis Basic magnesium carbonate Solid-state NMR

Nest-type NCM ■ Pt/C with oxygen capture character as advanced electrocatalyst for oxygen reduction reaction

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Journal of Energy Chemistry 2022年第8期31卷 304-312,I0009页

作者： Teng Chen Yida Xu Deming Meng Xuefeng Guo Yan Zhu luming peng Jianqiang Hu Weiping Ding Key Lab of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023JiangsuChina Department of Aviation Oil and Material Air Force Logistics AcademyXuzhou 221000Jiangsu.China

A unique nest-type catalyst has been designed with a nest of oxygen capture surrounding catalytic Pt centers, which shows much promoted performance, on the base of Pt/C catalyst, for oxygen reduction reaction(ORR). The nest is constructed with nitrogen-doped carbon matrix(NCM), derived from the controlled carbonization of PANI precursor, to cover Pt/C catalyst. The unique structure of the catalyst(denoted as NCM■ Pt/C) has many merits. Firstly, it can capture oxygen both in air and in acidic electrolyte. Compared with naked Pt/C, it is found that, in air, the oxygen concentration within the porous nest of NCM surrounding Pt/C particles is ~13 times higher than atmospheric oxygen concentration and, in acidic electrolyte, the concentration of activated oxygen over the catalyst NCM■ Pt/C rise to~1.9 times. Secondly, the NCM nest offers a special electronic modulation on Pt centers toward modified ORR kinetics and then catalytic performances. With these merits, compared with Pt/C, the NCM■ Pt/C catalyst shows 3.2 times higher turnover frequency value and 2.9 times enhanced specific activity for ORR with half-wave potential at 0.894 V. After 50,000 sweeping cycles, the NCM■ Pt/C catalyst retains~66% mass activity and still has advantages over the fresh Pt/C catalyst. We envision that the nest-type catalyst provides a new idea for progress of practical Pt/C ORR catalyst.

关键词： Oxygen reduction reaction Surrounding environment Nest-type catalyst Oxygen capture Electronic modulation

Rational design of 3D porous niobium carbide MXene/rGO hybrid aerogels as promising anode for potassium-ion batteries with ultrahigh rate capability

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Nano Research 2023年第2期16卷 2463-2473页

作者： Cong Liu Zhitang Fang Xiaoge Li Jinhua Zhou Gang Yang luming peng Xuefeng Guo Weiping Ding Wenhua Hou Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China Suzhou Key Laboratory of Functional Ceramic Materials Changshu Institute of TechnologyChangshu 215500China

An effective method is designed to construct three-dimensional(3D)Nb_(2)C/reduced graphene oxide(rGO)hybrid aerogels through a low-temperature graphene oxide(GO)-assisted hydrothermal self-assembly followed by freeze-drying and annealing.The intimately coupled Nb_(2)C/rGO hybrid aerogel combines the advantages of large specific surface area and rich 3D interconnected porous structure of aerogel as well as high conductivity and low potassium diffusion energy barrier of Nb_(2)C,which not only effectively prevents the self-restacking of Nb2C nanosheets to allow more active sites exposed and accommodate the volume change during the charge/discharge process,but also increases the accessibility of electrolyte and promotes the rapid transfer of ions/electrons.As a result,Nb_(2)C/rGO-2 as the anode of potassium ion batteries(KIBs)delivers a large reversible specific capacity(301.7 mAh·g^(−1)after 500 cycles at 2.0 A·g^(−1)),an ultrahigh rate capability(155.5 mAh·g^(−1)at 20 A·g^(−1)),and an excellent long-term large-current cycle stability(198.8 mAh·g^(−1)after 1,000 cycles at 10 A·g^(−1),with a retention of 83.3%).Such a high-level electrochemical performance,especially the ultrahigh rate capability,is the best among transition metal carbides and nitride(MXene)-based materials reported so far for KIBs.The diffusion kinetics of K+is investigated thoroughly,and the synergetic charge–discharge mechanism and the structure–performance relationship of Nb_(2)C/rGO are revealed explicitly.The present work provides a good strategy to solve the self-restacking problem of two-dimensional materials and also enlarges the potential applications of MXenes.

关键词： niobium-based transition metal carbides(Nb_(2)C MXene) reduced graphene oxide(rGO) hybrid aerogel potassium ion batteries ultrahigh rate capability

Ultrahigh rate capability of 1D/2D polyaniline/titanium carbide(MXene)nanohybrid for advanced asymmetric supercapacitors

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Nano Research 2022年第1期15卷 285-295页

作者： Jinhua Zhou Qi Kang Shuchi Xu Xiaoge Li Cong Liu Lu Ni Ningna Chen Chunliang Lu Xizhang Wang luming peng Xuefeng Guo Weiping Ding Wenhua Hou Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Department of Polymer Science and Engineering Shanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China Analytical Testing Center Yangzhou UniversityYangzhou 225009China

High energy density and enhanced rate capability are highly sought-after for supercapacitors in today's mobile world.In this work,polyaniline/titanium carbide(MXene)(PANI/Ti3C2Tx)nanohybrid is synthesized through a facile and cost-effective self-assembly of.one-dimensional(10)PANI nanofibers and two-dimensional(20)Ti3C2Tx nanosheets.PANl!Ti3C2Tx delivers greatly improved specific capacitance,ultrahigh rate capability(67%capacitance retention from 1 to 100 A·g^(-1))as well as good cycle stability.Electrochemical kinetic analysis reveals that PANI/Ti3C2Tx is featured with surface capacitance-dominated process and has a quasi-reversible kinetics at high scan rates,giving rise to an ultrahigh rate capability.By using PANl!Ti3C2Tx as positive electrode,an 1.8 V aqueous asymmetric supercapacitor(ASC)is successfully assembled,showing a maximum energy density of 50.8 Wh·kg^(-1)·(at 0.9 kW-kg-1)and a power density of 18 kW·kg^(-1)(at 26 Wh·kg^(-1)).Moreover,an 3.0 V organic ASC is also elaborately fabricated,·by using PANI/Ti3C2Tx,achieving an ultrahigh energy density of 67.2 Wh·kg^(-1)(at 1.5 kW·kg^(-1))and a power density of 30 kW·kg^(-1)·(at 26.8 Wh·kg^(-1)).The present work not only improves fundamental understanding of the structure-property relationship towards ultrahigh rate capability electrode materials,but also provides valuable guideline for the rational design of high-performance:energy storage devices with both high energy and power densities.

关键词： MXene polyaniline nanohybrid asymmetric supercapacitor rate capability

Recent progress in investigations of surface structure and properties of solid oxide materials with nuclear magnetic resonance spectroscopy

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Chinese Chemical Letters 2018年第6期29卷 747-751页

作者： Jia-Huan Du luming peng Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical Engineering Nanjing University

Solid oxide materials have widespread applications which are often associated with their surface structure and properties. Solid-state nuclear magnetic resonance（NMR） spectroscopy is one of the most powerful methods that give detailed local structural information of solid materials. Recent developments in dynamic nuclear polarization（DNP） NMR spectroscopy and17 O surface-selective isotopic labeling provide more opportunities in investigations of surface structure and properties of oxide materials. We describe in this review some of the latest progress in this field. DNP NMR can enhance the sensitivity of surface sites on the oxides by one to two order of magnitude, making very low concentrated species on the surface of oxides visible in NMR spectroscopy. On the basis of surface-selective17 O isotopic labeling,17 O NMR spectroscopy is now able to distinguish surface oxygen species on the different facets or different surface layers in oxide nanostructures. The nature of these facets can also be probed with help of31 P NMR spectroscopy along with phosphorous-containing probe molecules.

关键词： NMR Oxide Surface ^17O DNP

Adjacent acid sites cooperatively catalyze fructose to 5-hydroxymethylfurfural in a new, facile pathway

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Journal of Energy Chemistry 2020年第8期29卷 112-117,I0004页

作者： Xia Yu Yueying Chu Lei Zhang Hui Shi Mingjiang Xie luming peng Xuefeng Guo Wei Li Nianhua Xue Weiping Ding Key Lab of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093JiangsuChina State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Center for Magnetic ResonanceWuhan Institute of Physics and Mathematicsthe Chinese Academy of SciencesWuhan 430071HubeiChina Institute of Theoretical and Computational Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093JiangsuChina Department of Chemistry and Catalysis Research Center Technische Universitat MiinchenLichtenbergstr.4.85747 GarchingGermany

To study the effect of adjacent hydroxyl to the active sites, several acid catalysts, i.e. substituted benzoic acids with adjacent carboxyl are employed in the fructose dehydration to 5-hydroxymethylfurfural(HMF).Experimental results reveal that Br?nsted acid sites with adjacent carboxyl present higher catalytic ability than isolated ones. Computational results suggest that the adjacent sites lead to co-interaction on fructose, corresponding more stable transition state and faster HMF formation rate. Based on the enhancement from the adjacent sites, a novel ordered mesoporous carbon(OMC) full of carboxyls in surface is prepared and turns out to be an effective solid catalyst for HMF production from fructose derived from biomass.

关键词： Fructose dehydration Adjacent sites Cooperative catalysis 5-Hydroxymethylfurfural

Carbon nitride with encapsulated nickel for semi-hydrogenation of acetylene: pyridinic nitrogen is responsible for hydrogen dissociative adsorption

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Science China Chemistry 2018年第8期61卷 1014-1019页

作者： Teng Fu Tao Wang Hongfang Sun Yida Xu Zhen Dong Xiangke Guo luming peng Yan Zhu Zhaoxu Chen Weiping Ding Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical Engineering Nanjing University

A new mechanism of catalyst has been demonstrated in this article. With the interaction between carbon nitride(CN) and encapsulated nickel, the CN in the catalyst has been endowed with new active sites for the adsorption and activation of hydrogen while nickel itself is physically isolated from the contact with reactive molecules. For the selective hydrogenation of acetylene in large amount of ethylene, the catalyst shows excellent ethylene selectivity than the nickel catalyst itself, which is almost totally unselective. Meanwhile, the CN itself is inactive for the reaction. The results of characterization demonstrate that pyridinic nitrogen doped in the carbon matrix should be the active sites for hydrogen dissociative adsorption. The theoretical calculations further confirm the results and provide with the detail in the electron transfer between nickel and CN in the catalyst. The current results supply a new concept for design of high performance catalyst.

关键词：镍催化剂碳氮化物选择加氢吸附乙炔分离高效催化剂相互作用

Schiff-base silver nanocomplexes formation on natural biopolymer coated mesoporous silica contributed to the improved curative effect on infectious microbes

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Nano Research 2021年第8期14卷 2735-2748页

作者： Ling Cai Yanqiang Huang Yuanyuan Duan Qiao Liu Qilan Xu Jia Jia Jianming Wang Qian Tong Peipei Luo Yujie Wen luming peng Qian Wu Xudong Hang Huijun Jiang Ping Zhu Yanmei Yang Boshen Zhou Liping Zeng Hongkai Bi Jin Chen Center for Global Health The Key Laboratory of Modern ToxicologyMinistry of EducationSchool of Public HealthNanjing Medical UniversityNanjing 211166China Department of Pathogen Biology Jiangsu Key Laboratory of Pathogen BiologyNanjing Medical UniversityNanjing 211166China Research Center for the Prevention and Treatment of Drug Resistant Microbial Infecting Youjiang Medical University for Nationalities Baise 533000China The Laboratory Center for Basic Medical Sciences Nanjing Medical UniversityNanjing 211166China Key Laboratory of Mesoscopic Chemistry of MOE and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China School of Pharmacy Nanjing Medical UniversityNanjing 211166China Department of Gastroenterology Sir Run Run HospitalNanjing Medical UniversityNanjing 211166China Key Laboratory of Antibody Technique of National Health Commission Nanjing Medical UniversityNanjing 211166China

Infectious microbes that spread easily in healthcare facilities remain as the severe threat for the public health,especially among immunocompromised populations.Given the intricate problem of dramatic increase in resistance to common biocides,the development of safe and efficient biocide formulated agents to alleviate drug resistance is highly demanding.In this study,Schiff-base ligands were successfully formed on natural biopolymer of epsilon-poly-L-lysine(ε-PL)decorated aldehyde functionalized mesoporous silica SBA-15(CHO-SBA-15)for the selective coordination of silver ions,which was affirmed by various physicochemical methods.Besides the identified broad-spectrum antibacterial activities,the as-prepared Schiff-base silver nanocomplex(CHO-SBA-15/ε-PL/Ag,CLA-1)exhibited an improved inhibitory effect on infectious pathogen growth typified by Escherichia coli and Staphylococcus aureus in comparison with two control silver complexes without Schiff-base conjugates,SBA-15/ε-PL/Ag and CHO-SBA-15/Ag,respectively.In addition,CLA-1 remarkably inhibited the growth of Mycobacterium tuberculosis due to the excellent antimicrobial activity of silver species.Significantly,CLA-1 kills Candida albicans cells,inhibits biofilm formation,and eliminates preformed biofilms,with no development of resistance during continuous serial passaging.The antifungal activity is connected to disruption of bacterial cell membranes and increased levels of intracellular reactive oxygen species.In mouse models of multidrug-resistant C.albicans infection,CLA-1 exhibited efficient in vivo fungicidal efficacy superior to two antifungal drugs,amphotericin B and fluconazole.Moreover,CLA-1 treatment induces negligible toxicity against normal tissues with safety.Therefore,this study reveals the pivotal role of the molecular design of Schiff-base silver nanocomplex formation on biopolymer surface-functionalized silica mesopores as a green and efficient nanoplatform to tackle infectious microbes.

关键词： biopolymer drug delivery mesoporous silica silver nanoparticles antimicrobial drug resistance

Synergistic effects of Nb and Mo on hydrogen-induced cracking of pipeline steels:A combined experimental and numerical study

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Journal of Materials Science & Technology 2023年第27期158卷 156-170页

作者： Shiqi Zhang luming Qi Shilong Liu Zhixian peng Y.Frank Cheng Feng Huang Jing Liu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering University of CalgaryCalgaryAB T2N 1N4Canada Hubei Engineering Technology Research Centre of Marine Materials and Service Safety Wuhan University of Science and TechnologyWuhan 430081China

The synergistic effects of Nb and Mo on hydrogen-induced cracking(HIC)of pipeline steels were studied experimentally and numerically.The results showed that Mo was primarily segregated at grain-boundaries(GBs)or solid-dissolved in the matrix,while most Nb and a small amount of Mo formed dis-persed(Nb,Mo)C nano-precipitates and refined the microstructure.Compared with Nb alloying,the multi-ple additions of Nb-Mo played dual roles in affecting H diffusion:primarily,the H-traps densities such as GBs,precipitates,and solute Mo atoms increased,providing an advantage;however,Mo slightly reduced the H-trapping capacity of precipitates,playing an adverse role.Nonetheless,the beneficial effects far outweighed the adverse effects,thereby reducing H diffusivity and inhibiting crack initiation.Addition-ally,Nb and Mo hindered crack propagation synergistically as follows:(i)Mo enhanced GB cohesion by repelling H,impeding intergranular cracking and hydrogen-enhanced decohesion(HEDE);(ii)Nb reduced the proportion of3/high-angle grain boundaries,increasing cracking resistance;(iii)(Nb,Mo)C precip-itates impeded H-dislocation interactions,reducing the hydrogen-enhanced localized plasticity(HELP).

关键词： Hydrogen-induced cracking Nb-Mo microalloying Hydrogen permeation Precipitate Pipeline steel