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Science China chemistry 2010年第2期53卷 297-309页

作者： gao Fang LIANG WanZhen ZHAO Yi Hefei National Laboratory for physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China state key Laboratory of {2. chemistry of solid surfaces and Department of chemistry Xiamen UniversityXiamen 361005China

Absorption and photoluminescence spectroscopies are useful tools to study the photo-physical properties of materials. The theoretical methods for calculation of the spectra of molecules/supermolecules and aggregates, whose structures can differ significantly, are reviewed from the viewpoint of computational efficiency. Several model compounds/multimers are taken as examples for the spectral calculations. The numerical results achieve a satisfactory agreement between the theory and experiment.

关键词： vibrationally resolved absorption and photoluminescence spectroscopies single chromophore multichromophoric oligomers aggregates time-dependent density functional theory(TD-DFT)

EPR and DFT Study of the Polycyclic Aromatic Radical Cations from Friedel-Crafts Alkylation Reactions

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Chinese Journal of Chemical Physics 2009年第1期22卷 51-56页

作者： Tao Wang An-an Wu Li-guo gao Han-qing Wang Department of chemistry and Chemical Engineering Heze University Heze 274015 China state key Laboratory of {2. chemistry of solid surfaces School of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China College of chemistry and Chemical Engineering Yulin College Yulin 719000 China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Electron paramagnetic resonance and electron-nuclear double resonance methods were used to study the polycyclic aromatic radical cations produced in a Friedel-Crafts alkylating sys- tem, with m-xylene, or p-xylene and alkyl chloride. The results indicate that the observed electron paramagnetic resonance spectra are due to polycyclic aromatic radicals formed from the parent hydrocarbons. It is suggested that benzyl halides produced in the Friedel-Crafts alkylation reactions undergo Scholl self-condensation to give polycyclic aromatic hydrocar- bons, which are converted into corresponding polycyclic aromatic radical cations in the presence of AlCl3. The identification of observed two radicals 2.6-dimethylanthracene and 1,4,5,8-tetramethylanthraeene were supported by density functional theory calculations using the B3LYP/6-31G（d,p）//B3LYP/6-31G（d） approach. The theoretical coupling constants support the experimental assignment of the observed radicals.

关键词： Electron paramagnetic resonance Eelectron-nuclear double resonance Density functional theory Polycyclic aromatic radical cation

Ion-vacancy coupled charge transfer model for ion transport in concentrated solutions

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Science China chemistry 2019年第4期62卷 515-520页

作者： Yu gao Jun Huang Yuwen Liu Jawei Yan Bingwei Mao Shengli Chen Hubei key Laboratory of Electrochemical Power Sources Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) Department of Chemistry Wuhan University Hunan Provincial key Laboratory of Chemical Power Sources College of Chemistry and Chemical Engineering Central South University state key Laboratory of {2. chemistry of solid surfaces Department of Chemistry Xiamen University

We present a conceptual framework for understanding and formulating ion transport in concentrated solutions, which pictures the ion transport as an ion-vacancy coupled charge transfer reaction. A key element in this picture is that the transport of an ion from an occupied to unoccupied site involves a transition state which exerts double volume exclusion. An ab initio random walk model is proposed to describe this process. Subsequent coarse-graining results in a continuum formula as a function of chemical potentials of the constituents, which are further derived from a lattice-gas model. The subtlety here is that what has been taken to be the chemical potential of the ion in the past is actually that of the ion-vacancy couple. By aid of this new concept, the driving force of ion transport is essentially the chemical affinity of the ion-vacancy coupled charge transfer reaction, which is a useful concept to unify transport and reaction, two fundamental processes in electro{2.. This phenomenological model is parameterized for a specific material by the aid of first-principles calculations. Moreover, its extension to multiple-component systems is discussed.

关键词： concentrated solutions ion dynamics ion volume effect chemical affinity ion-vacancy couple

In situ Raman spectroscopy reveals the mechanism of titanium substitution in P2.Na_(2.3)Ni_(1/3)Mn_(2.3)O_(2.: Cathode materials for sodium batteries

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Journal of Energy chemistry 2021年第2期30卷 323-328,I0011页

作者： Xiao-Bin Zhong Chao He Fan gao Zhong-Qun Tian Jian-Feng Li School of Mechanical and Power Engineering North University of ChinaTaiyuan 030051ShanxiChina state key Laboratory of {2. chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Layered P2.Na_(2.3)Ni_(1/3)Mn_(2.3)O_2.is a promising cathode material. It exhibits a high capacity and suitable operating voltage and undergoes a phase transition from P2.to O2.during charge/*** have used Ti substitution to improve the cathode, yet the chemical principles that underpin elemental substitution and functional improvement remain unclear. To clarify these principles, we used in situ Raman spectroscopy to monitor chemical changes in P2.Na2.3 Ni1/3 Mn1/3 Ti1/3 O2.and P2.Na_(2.3)Ni_(1/3)Mn_(2.3)O_2.during charge/discharge. Based on the change in the A_(1g) and E_g peaks during charge/discharge, we concluded that Ti substitution compressed the transition metal layer and expanded the planar oxygen layer in the unit cell. Titanium stabilized the P2.phase structure, which improved the cycling stability of P2.NaNMT. Our results provide clear theoretical support for future research on modifying electrodes by elemental substitution.

关键词： In situ Raman spectroscopy P2.Na_(2.3)Ni_(1/3)Mn_(2.3)O_(2. Titanium substitution

Catalysis under shell： Improved CO oxidation reaction confined in Pt@h-BN core-shell nanoreactors

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Nano Research 2017年第4期10卷 1403-1412页

作者： Mengmeng Sun Qiang Fu Lijun gao Yanping Zheng Yangyang Li Mingshu Chen Xinhe Bao state key Laboratory of Catalysis iChEM Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Department of Chemical Physics University of Science and Technology of China Hefei230026 China state key Laboratory of {2. chemistry of solid surfaces Department of Chemistry Xiamen University Xiamen 361005 China

Core-shell nanostructures consisting of active metal cores and protective shells often exhibit enhanced catalytic performance, in which reactants can access a small part of the core surfaces through the pores in the shells. In this study, we show that Pt nanoparticles （NPs） can be embedded into few-layer hexagonal boron nitride （h-BN） overlayers, forming Pt@h-BN core-shell nanocatalysts. The h-BN shells not only protect the Pt NPs under harsh conditions but also allow gaseous molecules such as CO and 02.to access a large part of the Pt surfaces through a facile intercalation process. As a result, the Pt@h-BN nanostructures act as nanoreactors, and CO oxidation reactions with improved activity, selectivity, and stability occur at the core-shell interfaces. The confinement effect exerted by the h-BN shells promotes the Pt-catalyzed reactions. Our work suggests that two-dimensional shells can function as robust but flexible covers on nanocatalyst surfaces and tune the surface reactivity.

关键词： core-shell CO oxidation Pt hexagonal boron nitride nanoreactor

三合一设计策略促进超细PtNiW@WOx核壳纳米线氢氧化电催化剂的CO耐受性

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Science China Materials 2024年第6期67卷 1866-1875页

作者：刘巍杨馥榕孙土来黄晨明赖文川杜佳峰叶进裕曾昱嘉高磊黄宏文 College of Materials Science and Engineering Hunan UniversityChangsha 410082China Center for Electron Microscopy State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China College of chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China state key Laboratory for {2. chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Research Institute of Hunan University Shenzhen 518055China

铂(Pt)是质子交换膜燃料电池(PEMFCs)阳极氢氧化反应(HOR)中最先进的电催化剂.然而,Pt催化剂对CO(工业低成本氢燃料中的杂质)极度敏感从而中毒,这会引起器件性能的急剧衰退,导致器件运行成本高.因此,提高Pt催化剂的CO耐受性对PEMFCs的... 详细信息

铂(Pt)是质子交换膜燃料电池(PEMFCs)阳极氢氧化反应(HOR)中最先进的电催化剂.然而,Pt催化剂对CO(工业低成本氢燃料中的杂质)极度敏感从而中毒,这会引起器件性能的急剧衰退,导致器件运行成本高.因此,提高Pt催化剂的CO耐受性对PEMFCs的商业化推广至关重要.在此,我们设计合成了一种独特的PtNiW@WO_(x)核壳纳米线来提高Pt基催化剂对CO的耐受能力.机理研究表明,表面无定形的WO_(x)壳层可以作为分子围栏,在动力学上阻碍CO扩散到达Pt位点.在热力学上,Ni和W元素合金化产生的电子效应可以使Pt的d带中心降低,减弱CO在Pt位点上的化学吸附.此外,亲氧W元素可以加速水的解离,提供更多OH活性物种,促进CO的氧化脱附.因此,在1000ppm CO/H_(2.条件下,所设计的PtNiW@WO_(x)核壳纳米线催化剂表现出优异的HOR抗CO中毒性能,在4000 s后仍能保持超过90%的HOR电流密度,超过了原始的PtNi纳米线和目前报道的绝大多数Pt基催化剂.

关键词： hydrogen oxidation reaction Pt-based electrocatalyst CO tolerant fuel cell catalyst design

In situ Raman,FTIR,and XRD spectroscopic studies in fuel cells and rechargeable batteries

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Nano Research 2023年第4期16卷 4855-4866页

作者： Fan gao Xiang-Dong Tian Jia-Sheng Lin Jin-Chao Dong Xiu-Mei Lin Jian-Feng Li Xiamen Cardiovascular Hospital State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringCollege of EnergyXiamen UniversityXiamen 361005China Department of chemistry and Environment Science Fujian Province University Key Laboratory of Analytical ScienceMinnan Normal UniversityZhangzhou 363000China

As state-of-the-art electrochemical energy conversion and storage(EECS)techniques,fuel cells and rechargeable batteries have achieved great success in the past ***,modern societies’ever-growing demand in energy calls for EECS devices with high efficiency and enhanced performance,which mainly rely on the rational design of catalysts,electrode materials,and electrode/electrolyte interfaces in EESC,based on in-deep and comprehensive mechanistic understanding of the relevant electrochemical redox *** an understanding can be realized by monitoring the dynamic redox reaction processes under realistic operation conditions using in situ techniques,such as in situ Raman,Fourier transform infrared(FTIR),and X-ray diffraction(XRD)*** techniques can provide characteristic spectroscopic information of molecules and/or crystals,which are sensitive to structure/phase changes resulted from different electrochemical working conditions,hence allowing for intermediates identification and mechanisms *** review described and summarized recent progress in the in situ studies of fuel cells and rechargeable batteries via Raman,FTIR,and XRD *** applications of these in situ techniques on typical electrocatalytic electrooxidation reaction and oxygen reduction reaction(ORR)in fuel cells,on representative high capacity and/or resource abundance cathodes and anodes,and on the solid electrolyte interface(SEI)in rechargeable batteries are *** discuss how these techniques promote the development of novel EECS systems and highlight their critical importance in future EECS research.

关键词： in situ spectroscopy Raman Fourier transform infrared spectroscopy(FTIR) X-ray diffraction(XRD) fuel cells rechargeable batteries

Integrated identification of growth pattern and taxon of bacterium in gut microbiota via confocal fluorescence imaging‐oriented single‐cell sequencing

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mLife 2022年第3期1卷 350-358页

作者： Juan gao Di Sun Bei Li Chaoyong Yang Wei Wang Shanghai key Laboratory for Nucleic Acid chemistry and Nanomedicine Institute of Molecular MedicineRenji HospitalShanghai Jiao Tong University School of MedicineShanghaiChina state key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchunChina The MOE key Laboratory of Spectrochemical Analysis and Instrumentation Key Laboratory for Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid SurfacesDepartment of Chemical BiologyXiamen UniversityCollege of Chemistry and Chemical EngineeringXiamenChina

Despite the fast progress in our understanding of the complex functions of gut microbiota,it is still challenging to directly investigate the in vivo microbial activities and processes on an individual cell *** gain knowledge of the indigenous growth/division patterns of the diverse mouse gut bacteria with a relatively high throughput,here,we propose an integrative strategy,which combines the use of fluorescent probe labeling,confocal imaging with single‐cell sorting,and *** gut bacteria sequentially labeled by two fluorescent D‐amino acid probes in vivo were first imaged by confocal microscopy to visualize their growth patterns,which can be unveiled by the distribution of the two fluorescence signals on each *** cells of interest on the imaging slide were then sorted using a laser ejection equipment,and the collected cells were then sequenced individually to identify their *** strategy allows integrated acquirement of the growth pattern knowledge of a variety of gut bacteria and their genomic information on a single‐cell basis,which should also have great potential in studying many other complex bacterial systems.

关键词： bacterial growth pattern confocal imaging fluorescent D‐amino acid probe in vivo labeling single‐cell sequencing

Asymmetric transfer hydrogenation of ketones catalyzed by nickel complex with new PNO-type ligands

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Chinese Chemical Letters 2012年第5期23卷 533-536页

作者： Zhen Rong Dong Yan Yun Li Shen Luan Yu Guo Song Sun Jing Xing gao state key Laboratory for {2. chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Guangxi Research Institute of Chemical Industry Nanning 530001China

The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl_3,and fully characterized by IR,NMR and EIMS *** ligands were employed with a simple Ni complex Ni（PPh_s）_2.l_2.in situ as catalytic systems for asymmetric transfer hydrogenation of ketones,and the corresponding optical alcohols were obtained with up to 84%ee under mild conditions.

关键词： Nickel complex NPO-type ligand Asymmetric transfer hydrogenation Ketones

Easily Obtaining Excellent Performance High-voltage LiCoO_(2.via Pr_(6)O_(11)Modification

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Energy & Environmental Materials 2023年第2期6卷 34-44页

作者： Yongcong Huang Chenjie Xu Jingguo gao Liao Shen Qian Liu Guiying Zhao Qingshui Xie Yingbin Lin Jiaxin Li Zhigao Huang College of Physics and Energy Fujian Provincial Solar Energy Conversion and Energy Storage Engineering Technology Research CenterFujian Normal UniversityFuzhou 350117China Fujian Provincial key Laboratory of Quantum Manipulation and New Energy Materials Fuzhou 350117China Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering Fuzhou 350117China state key Laboratory for {2. chemistry of solid surfaces Fujian Key Laboratory of Materials GenomeCollaborative Innovation Center of Chemistry for Energy MaterialsCollege of MaterialsXiamen UniversityXiamen 361005China

Developing an effective method to synthesize high-performance high-voltage LiCoO_(2. is essential for its industrialization in lithium batteries(LIBs).This work proposes a simple mass-produced strategy for the first time,that is,negative temperature coefficient thermosensitive Pr_(6)O_(11) nanoparticles are uniformly modified on LiCoO_(2. to prepare LiCoO_(2.@Pr_(6)O_(11)(LCO@PrO)via a liquid-phase mixing combined with annealing *** at 2.4 mA g−1,the modified LCO@PrO electrodes deliver excellent 4.5 V high-voltage cycling performance with capacity retention ratios of 90.8%and 80.5%at 2. and 60℃,being much larger than those of 2..8%and 63.2.for bare LCO *** effective strategies were used to clearly unveil the performance enhancement mechanism induced by Pr_(6)O_(11) *** is discovered that Pr_(6)O_(11) can improve interface compatibility,exhibit improved conductivity at elevated temperature,thus enhance the Li^(+)diffusion kinetics,and suppress the phase transformation of LCO and its resulting mechanical *** 450 mAh LCO@PrO‖graphite pouch cells show excellent LIB performance and improved thermal safety ***,the energy density of such pouch cell was increased even by~42.at 5 *** extremely convenient technology is feasible for producing high-energy density LIBs with negligible cost increase,undoubtedly providing important academic inspiration for industrialization.

关键词： high-voltage LiCoO_(2. pouch cell Pr_(6)O_(11)modification simple massproduction thermal safety