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Journal of Environmental Sciences 2019年第1期31卷 388-395页

作者： Zhenli Sun Fengkui Duan Kebin He Jingjing Du liu Yang Hui li Tao Ma Shuo Yang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Fine particles associated with haze pollution threaten the health of more than 400 million people in china. It is therefore of great importance to thoroughly investigate and understand their composition. To determine the physicochemical properties in atmospheric fine particles at the micrometer level, we described a sensitive and feasible surface-enhanced Raman scattering(SERS) method using Ag foil as a substrate. This novel method enhanced the Raman signal intensities up to 10,000 a.u. for ν(NO_3^-) in fine *** SERS effect of Ag foil was further studied experimentally and theoretically and found to have an enhancement factor of the order of ～10~4. Size-fractionated real particle samples with aerodynamic diameters of 0.4–2.5 μm were successfully collected on a heavy haze day,allowing ready observation of morphology and identification of chemical components, such as soot, nitrates, and sulfates. These results suggest that the Ag-foil-based SERS technique can be effectively used to determine the microscopic characteristics of individual fine particles, which will help to understand haze formation mechanisms and formulate governance policies.

关键词： SERS PM2.5 Individual particle Atmospheric

Electrochemical process of sulfur in carbon materials from electrode thickness to interlayer

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Journal of Energy chemistry 2019年第4期28卷 119-124页

作者： Xiaonan Tang Zhenhua Sun Huicong Yang Haitao Fang Fei Wei Hui-Ming Cheng Shuping Zhuo Feng li school of chemical engineering Shandong University of Technology Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences school of Materials Science and engineering University of Science and Technology of China school of Materials Science and engineering Harbin Institute of Technology Department of chemical engineering Tsinghua University Tsinghua-Berkeley Shenzhen Institute Tsinghua University

Lots of efforts have been done on different porous carbon materials as cathode for lithium–sulfur(li–S)battery. However, seldom researches have been done on the relationship between cathode thickness and electrochemical performance. Our work investigates the relation between electrochemical performance and cathode thickness with typical porous carbon materials. We explain the phenomenon that only a modest cathode thickness can have the most adequate electrochemical reaction trend through the aspect of thermodynamics(chemical potential) so that the best electrochemical performance can be ***, interlayer can remit the shuttle effect but hinder the lithium ion diffusion process simultaneously. And we verify the effect of interlayer thickness on the shuttle effect and lithium ion diffusion process.

关键词： lithium-sulfur battery Electrochemical reaction Cathode thickness chemical potential Ion diffusion

Shape-dependence in seeded-growth of Pd-Cu solid solution from Pd nanostructure towards methanol oxidation electrocatalyst

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Nano Research 2023年第7期16卷 9116-9124页

作者： lianxi Si Hui li Yu Zhang Donghao Zhang Xiaowei An Mengmeng Yao Yuanyuan Shao Jesse Zhu Shi Hu school of chemical engineering and Technology Tianjin UniversityTianjin 300072China Department of chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China College of Environmental Science and engineering Taiyuan University of TechnologyTaiyuan 030024China

Ultrathin Pd nanosheets(NSs)have great advantages in catalysis due to their large specific surface area and high percentage of under-coordinated ***,the electrochemical performance still can be improved via composition-controllable growth of their solid ***,seeded alloying strategy was proposed to synthesize Pd-Cu solid solution from Pd NSs and Pd-Cu nanostructures with tunable molar ratios obtained by changing the amount of Cu *** compared to the pristine Pd NSs,the Pd-Cu solid solution shows significantly enhanced methanol oxidation reaction(MOR)performance over those of Pd NSs and homemade Pd/C as the incorporation of Cu weakens the adsorption of CO intermediate on Pd in the MOR *** choice of template is pivotal to the growth,as a shape-dependent behavior could be identified in the alloying of Cu with Pd nanosheets enclosed by{111}and{100}facets,Pd nanocubes enclosed by{100}facet,and Pd nano-tetrahedrons enclosed by{111}*** Pd-Cu solid solution with tunable composition can only be obtained from Pd NSs and the shape-dependent alloying process is mainly determined by the diffusion barrier and the minimum diffusion depth of the different facets.

关键词： Pd-Cu alloy nanosheets tunable composition methanol oxidation reaction optimized electronic structure weakened COadsorption

Na_(3)Zr_(2)Si_(2)PO_(12) solid-state electrolyte with glass-like morphology for enhanced dendrite suppression

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Rare Metals 2022年第12期41卷 4086-4093页

作者： Hang Su Shi-Wei Zhang Yi-Meng liu Chao Yang li-Xiao Zhang Sen Xin Ya You State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China university of Chinese Academy of Sciences International school of Materials Science and engineering Wuhan University of TechnologyWuhan 430070China

Rechargeable batteries based on solid-state electrolytes are of great interest and importance for the next-generation energy storage due to their high energy output and improved *** building the solid-state batteries,Na_(3)Zr_(2)Si_(2)PO_(12)(NZSP)represents a promising candidate as it features high chemical stability against air exposure and a high Na^(+)*** pellets were usually calcined at a high temperature,and the high volatility of Na and P elements easily led to the formation of impurity *** this work,the effects of calcination temperature and stoichiometry on the phase purity and ionic conductivity of the NZSP electrolyte were *** an elevated sintering temperature,the NZSP electrolyte showed a high ionic conductivity owing to decreased porosity,and the highest ionic conductivity at 30℃was observed to be 2.75×10^(-5)S·cm^(-1)with an activation energy of 0.41 *** the stoichiometry,the introduction of 5 mol%excessive P results in formation of more Na_(3)PO_(4) and glass-like phase at the grain boundary,which caused the blurred grain boundary and reduced grain barrier,and effectively suppressed Na dendrite growth,then accounted for improved cycling performance of a Na‖Na symmetric *** work provided insights on reasonable design and preparation of NZSP electrolyte towards practical realization of solid-state Na-metal batteries.

关键词： Na_(3)Zr_(2)Si_(2)PO_(12)(NZSP) Natrium superionic conductor(NASICON)solid-state electrolytes Grain boundary Ionic conductivity Glass-like morphology

Spatial configuration engineering of perylenediimide-based non-fullerene electron transport materials for efficient inverted perovskite solar cells

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Journal of Energy chemistry 2021年第5期30卷 374-382页

作者： Mengmeng Zheng Yawei Miao Ali Asgher Syed Cheng Chen Xichuan Yang liming Ding Huaming li Ming Cheng Institute for Energy Research School of Materials Science&EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina State Key Laboratory of Fine chemicals Institute of Artificial PhotosynthesisDUT−KTH Joint Education and Research Center on Molecular DevicesDalian University of Technology(DUT)Dalian 116024LiaoningChina Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

Due to their excellent photoelectron chemical properties and suitable energy level alignment with perovskite,perylene diimide(PDI)derivatives are competitive non-fullerene electron transport material(ETM)candidates for perovskite solar cells(PSCs).However,the conjugated rigid plane structure of PDI units result in PDI-based ETMs tending to form large aggregates,limiting their application and photovoltaic *** this study,to restrict aggregation and further enhance the photovoltaic performance of PDI-type ETMs,two PDI-based ETMs,termed PDO-PDI2(dimer)and PDO-PDI3(trimer),were constructed by introducing a phenothiazine 5,5-dioxide(PDO)core building *** research manifests that the optoelectronic properties and film formation property of PDO-PDI2 and PDO-PDI3 were deeply affected by the molecular spatial *** in PSCs,PDO-PDI3 with threedimensional spiral molecular structure,exhibits superior electron extraction and transport properties,further achieving the best PCE of 18.72%and maintaining 93%of its initial efficiency after a 720-h aging test under ambient conditions.

关键词： Non-fullerene Electron transport material Perovskite solar cell Inverted structure

Racemic X-ray structure of L-type calcium channel antagonist Calciseptine prepared by total chemical synthesis

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Science china chemistry 2018年第6期61卷 702-707页

作者： Chen-Chen Chen Shuai Gao Hua-Song Ai Qian Qu Chang-lin Tian Yi-Ming li High Magnetic Field Laboratory Chinese Academy of Sciences Hefei 230031 China school of life Sciences University of Science and Technology of China Hefei 230026 China school of Biological and Medical engineering Hefei University of Technology Hefei 230009 China Department of chemistry Tsinghua University Beijing 100084 China

Snake toxin Calciseptine as a natural antagonist of L-type calcium channel has potential drug values, but its structural information remains unknown. Here, we report the total chemical synthesis of Calciseptine by using hydrazide based native chemical ligation. The crystal structure of Calciseptine was determined by racemic protein crystallography technique. Compared to the structure of its homologous family protein, we found that Calciseptine is adopting a typical three-finger structure.

关键词： protein chemical synthesis calciseptine hydrazide based native chemical ligation racemic protein crystallography

Accurate machine learning models based on small dataset of energetic materials through spatial matrix featurization methods

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Journal of Energy chemistry 2021年第12期30卷 364-375,I0009页

作者： Chao Chen Danyang liu Siyan Deng lixiang Zhong Serene Hay Yee Chan Shuzhou li Huey Hoon Hng school of Materials Science and engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

A large database is desired for machine learning(ML) technology to make accurate predictions of materials physicochemical properties based on their molecular *** a large database is not available,the development of proper featurization method based on physicochemical nature of target proprieties can improve the predictive power of ML models with a smaller *** this work,we show that two new featurization methods,volume occupation spatial matrix and heat contribution spatial matrix,can improve the accuracy in predicting energetic materials' crystal density(ρ_(crystal)) and solid phase enthalpy of formation(H_(f,solid)) using a database containing 451 energetic *** mean absolute errors are reduced from 0.048 g/cm~3 and 24.67 kcal/mol to 0.035 g/cm~3 and 9.66 kcal/mol,*** leave-one-out-cross-validation,the newly developed ML models can be used to determine the performance of most kinds of energetic materials except *** ML models are applied to predict ρ_(crystal) and H_(f,solid) of CHON-based molecules of the 150 million sized PubChem database,and screened out 56 candidates with competitive detonation performance and reasonable chemical *** further improvement in future,spatial matrices have the potential of becoming multifunctional ML simulation tools that could provide even better predictions in wider fields of materials science.

关键词： Small database machine learning Energetic materials screening Spatial matrix featurization method Crystal density Formation enthalpy n-Body interactions

li_(7)La_(3)Zr_(2)O_(12)基氧化铝薄膜的制备及对固态电解质应用性能的影响

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化学研究与应用 2024年第5期36卷 1040-1047页

作者：杨彦飞陈志萍张立新杨晓峰刘烨昕中北大学化学与化工学院山西太原030051 中北大学高能电池材料与器件山西省重点实验室山西太原030051

li_(7)La_(3)Zr_(2)O_(12)(LLZO)具有离子电导率高、电化学窗口宽、与锂负极相容性好的特点,在锂离子电池领域成为了传统有机液态电解质的潜在替代品。然而,LLZO极易与空气中的CO_(2)、H_(2)O反应生成副产物li_(2)CO_(3),致使LLZO离子... 详细信息

li_(7)La_(3)Zr_(2)O_(12)(LLZO)具有离子电导率高、电化学窗口宽、与锂负极相容性好的特点,在锂离子电池领域成为了传统有机液态电解质的潜在替代品。然而,LLZO极易与空气中的CO_(2)、H_(2)O反应生成副产物li_(2)CO_(3),致使LLZO离子电导率降低,甚至丧失。针对这一问题,本研究采用先旋涂后烧结的方法在LLZO表面构筑氧化铝薄膜,借助致密氧化铝薄膜阻隔LLZO与空气的直接接触的特性,改善和提高LLZO的空气-水稳定性。结果表明,采用该方法可在LLZO表面构筑厚度约为13.34μm的无定形氧化铝薄膜层。该薄膜层有效提高了LLZO对气体的阻隔性,增大了LLZO表面疏水特性,在一定程度上抑制了li_(2)CO_(3)的生成。同时,由于渗入LLZO中氧化铝对空隙的填充作用,强化了离子传输特性,使负载薄膜后LLZO的离子传导的活化能从0.40 eV降低至0.28eV,离子电导率从4.48×10^(5)S·cm^(-1)提高到5.06×10^(-5)S·cm^(-1),提高了13%。

关键词： li_(7)La_(3)Zr_(2)O_(12) 固态电解质氧化铝薄膜透气性离子电导率活化能

Facile synthesis of hierarchical flower-like Ag/Cu2O and Au/Cu2O nanostructures and enhanced catalytic performance in electrochemical reduction of CO2

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Frontiers of chemical Science and engineering 2020年第5期14卷 813-823页

作者： Mengyun Wang Shengbo Zhang Mei li Aiguo Han Xinli Zhu Qingfeng Ge Jinyu Han Hua Wang Collaborative Innovation Center of chemical Science and engineering Key Laboratory for Green Chemical TechnologySchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Department of chemistry and Biochemistry Southern Illinois UniversityCarbondaleIL 62901USA

Novel,hierarchical,flower-like Ag/Cu2O and Au/Cu2O nanostructures were successfully fabricated and applied as efficient electrocatalysts for the electrochemical reduction of ***2O nanospheres with a uniform size of^180 nm were initially ***,Cu2O was used as a sacrificial template to prepare a series of Ag/Cu2O composites through galvanic *** varying the Ag/Cu atomic ratio,Ago.12/Cu2O,having a hierarchical,flower-like nanostructure with intersecting Ag nanoflakes encompassing an inner Cu2O sphere,was *** as-prepared Ag/Cu2O samples presented higher Faradaic efficiencies(FE)for CO and relatively suppressed H2 evolution than the parent Cu2O nanospheres due to the combination of Ag with Cu2O in the ***,the highest CO evolution rate was achieved with Ago.12/Cu2O due to the larger electroactive surface area furnished by the hierarchical *** same hier-archical flower-like structure was also obtained for the Auo./Cu2O composite,where the FEco(10%)was even higher than that of Ago.12/***,the results reveal that Ago.12/Cu2O and Auo./Cu2O both exhibit remarkably improved stability relative to *** study presents a facile method of developing hierarchical metal-oxide composites as fficient and stable electrocatalysts for the electrochemical reduction of CO2.

关键词： bimetallic nanostructure hierarchical metal/oxide nanomaterial galvanic replacement electrochemical reduction of CO2

Au(Ⅰ)-BSA nanocomposites with assembling-induced excitation-dependent multicolor emission for dynamic cell imaging

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Science china chemistry 2023年第1期66卷 174-184页

作者： Xuejuan Wang Guofeng liu Kuo Fu Xuping li Mengting Yao Qinghua Lu liangliang Zhu Xiang Ma Shanghai Key Laboratory of chemical Assessment and Sustainability Advanced Research Institute School of Chemical Science and EngineeringTongjiUniversityShanghai200092China Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision chemistry and Molecular engineering Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Scienceand TechnologyShanghai 200237China State Key Laboratory of Molecular engineering of Polymers Department of Macromolecular ScienceFudan University Shanghai 200438China

Excitation wavelength dependent(Ex-De) luminescent materials have attracted intense attention due to their great potential in multicolor bioimaging,dynamic anti-counterfeiting,and light emitting ***,it remains a formidable challenge to construct an Ex-De luminescent biomaterial with green starting materials,excellent biocompatibility,good water solubility,and multiple color emission for dynamic cell *** this work,nanocomposites based on the facile self-assembly strategy of bovine serum albumin(BSA) and Au(Ⅰ)-complex are rationally designed and synthesized to simultaneously present Ex-De fluorescence(429–516 nm) and decent phosphorescence(~615 nm) in a dilute aqueous *** analyses of spectroscopic and microscopic results reveal that the luminescent mechanism of Au(Ⅰ)-BSA nanocomposites is cluster-induced Ex-De fluorescence and metal-to-ligand charge transition(MLCT) based ***,based on the excellent biocompatibility,water-solubility and color-tunable emission over the entire visible region(360–800 nm),the Au(Ⅰ)-BSA nanocomposites are successfully used for cell imaging with multiple and switchable colors on *** is more,the solid tablets of Au(Ⅰ)-BSA nanoparticles showed pressure-responsive luminescence and decent room temperature *** work provides an assembling-induced emission strategy for the design of water-soluble,non-cytotoxic,and color-tunable luminescent biomaterials based on the composite of protein and Au nanoparticles.

关键词： nanocomposites excitation wavelength-dependent emission room temperature phosphorescence assembling-induced emission dynamic cell imaging