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Ultrafine ordered L1_(2)-Pt-Co-Mn ternary intermetallic nanoparticles as high-performance oxygen-reduction electrocatalysts for practical fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 157-165,I0005页

作者： Enping Wang Liuxuan Luo Yong Feng Aiming Wu Huiyuan Li Xiashuang Luo Yangge Guo Zehao Tan Fengjuan Zhu Xiaohui Yan Qi Kang Zechao Zhuang Daihui Yang Shuiyun Shen junliang zhang China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 201306China Institute of Fuel Cells Key Laboratory for Power Machinery and Engineering of MOESchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Tangfeng Energy Technology Co.Ltd. Shanghai 201306China State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China Department of Chemical Engineering Columbia UniversityNY 10027USA

The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.

关键词： Platinum Cobalt Manganese Oxygen reduction reaction Ordered intermetallic L1_(2)atomic structure Proton-exchange membrane fuel cell

Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 468-476页

作者： zhang Shouchuan LIU Kai MA Yan WANG Luyao SUN junliang Chinese Academy of Geological Sciences Beijing 100037China School of Water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District.

关键词： fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou District

Implementation of integrated nonlocal sensing for object shape and rotational speed

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 6-12页

作者： Zhenyu Guo Yunlong Wang Zehong Chang Jiawei Wang junliang Jia Pei zhang Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic DevicesSchool of PhysicsXi’an Jiaotong UniversityXi’an 710049China

The expeditious acquisition of information pertaining to objects through the utilization of quantum technology has been a perennial issue of concern.So far,the efficient utilization of information from dynamic objects with limited resources remains a significant challenge.Here,we realize a nonlocal integrated sensing of the object's amplitude and phase information by combining digital spiral imaging with the correlated orbital angular momentum states.The amplitude information is utilized for object identification,while the phase information enables us to determine the rotational speed.We demonstrate the nonlocal identification of a rotating object's shape,irrespective of its rotational symmetry,and introduce the concept of the correlated rotational Doppler effect,establishing a fundamental connection between this effect and the classical rotational Doppler effect,i.e.,that both rely on extracting crucial information from the spiral spectrum of objects.The present study highlights a promising pathway towards the realization of quantum remote sensing and imaging.

关键词： digital spiral imaging orbital angular momentum correlated rotational Doppler effect

Organic solar cells with D18 or derivatives offer efficiency over 19%

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Journal of Semiconductors 2024年第5期45卷 1-4页

作者： Erming Feng Chujun zhang Jianhui Chang Hengyue Li Liming Ding junliang Yang Hunan Key Laboratory for Super-microstructure and Ultrafast Process School of PhysicsCentral South UniversityChangsha 410083China Center for Excellence in Nanoscience Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-generation solar technologies[1−5].Thanks to breakthroughs in materials development,the power conversion efficiency(PCE)for single-junction OSCs has already surpassed 19%[6−13].The development of photoactive materials is pivotal in enhancing the PCEs,and several reviews have provided insights into materials design[14−18].Herein,we highlight single-junction OSCs based on D18 and its derivatives[19,20].

关键词： breakthrough insight derivatives

Synthesis of Axially Chiral Anilides Enabled by a Palladium/Ming-Phos-Catalyzed Desymmetric Sonogashira Reaction

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Chinese Journal of Chemistry 2022年第3期40卷 317-322页

作者： Bin Yang Junfeng Yang junliang zhang Deportment of Chemistry Fudon University2005 Songhu RoadShanghai 200438China

Atropisomeric anilides are one of important C-N axially chiral compounds.Compared with the A/-terminal functionalization to prepare such compounds,C-terminal functionalization strategies have been rarely reported.We describe herein an efficient synthesis of axially chiral anilides enabled by Pd-catalyzed desymmetric Sonogashira cross-coupling reactions with the use of a newly identified Ming-Phos.Moderate to high yields with high enantioselectivities(up to 98%ee)were obtained.

关键词： Atropisomerism Axially chiral anilides SadPhos Desymmetrization Sonogashira cross-coupling Kinetic resolution

Geochemical and Isotopic Techniques Constraints on the Origin,Evolution,and Residence Time of Low-enthalpy Geothermal Water in Western Wugongshan,SE China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 801-818页

作者： WANG Luyao LIU Kai MA Yan zhang Yaoyao TONG Jue JIA Wuhui zhang Shouchuan SUN junliang Chinese Academy of Geological Sciences Beijing 100037China School of Water Resources and Environment China University of Geoscience(Beijing)Beijing 100083China The Fourth Geological Brigade of Jiangxi Geological Bureau PingxiangJiangxi 337000China

Geothermal resources are increasingly gaining attention as a competitive,clean energy source to address the energy crisis and mitigate climate change.The Wugongshan area,situated in the southeast coast geothermal belt of China,is a typical geothermal anomaly and contains abundant medium-and low-temperature geothermal resources.This study employed hydrogeochemical and isotopic techniques to explore the cyclic evolution of geothermal water in the western Wugongshan region,encompassing the recharge origin,water-rock interaction mechanisms,and residence time.The results show that the geothermal water in the western region of Wugongshan is weakly alkaline,with low enthalpy and mineralization levels.The hydrochemistry of geothermal waters is dominated by Na-HCO_(3)and Na-SO_(4),while the hydrochemistry types of cold springs are all Na-HCO_(3).The hydrochemistry types of surface waters and rain waters are NaHCO_(3)or Ca-HCO_(3).The δD and δ^(18)O values reveal that the geothermal waters are recharged by atmospheric precipitation at an altitude between 550.0 and 1218.6 m.Molar ratios of maj or solutes and isotopic compositions of^(87)Sr/^(86)Sr underscore the significant role of silicate weathering,dissolution,and cation exchange in controlling geothermal water chemistry.Additionally,geothermal waters experienced varying degrees of mixing with cold water during their ascent.Theδ^(13)C values suggest that the primary sources of carbon in the geothermal waters were biogenic and organic.Theδ^(34)S value suggests that the sulfates in geothermal water originate from sulfide minerals in the surrounding rock.Age dating using 3H and^(14)C isotopes suggests that geothermal waters have a residence time exceeding 1 kaBP and undergo a long-distance cycling process.

关键词： geothermal water hydrochemistry isotope residence time Wugongshan area

Enantioselectivity Tunable Gold-Catalyzed Intermolecular[3+2]Cycloaddition of N-Allenamides with Nitrones

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Chinese Journal of Chemistry 2022年第12期40卷 1407-1412,I0002页

作者： Bing Xu Zhan-Ming zhang Jie Han Guangxin Gu junliang zhang Department of Chemistry Fudan University2005 Songhu RoadShanghai 200438China Department of Materials Science Fudan University2005 Songhu RoadShanghai 200438China Zhuhai Fudan Innovation Institute ZhuhaiGuangdong 519000China

A highly enantioselective gold-catalyzed intermolecular[3+2]cycloaddition of N-allenamides with nitrones was realized by the application of Ming-Phos M6 as a chiral ligand.Both enantiomers of the cycloadducts with opposite configuration could be obtained in high yields with high regio-and enantioselectivity by the employment of either diastereomer of the chiral ligand.The acidic N—H bond(hydrogen bonding)of sulfinamide moiety of Ming-Phos and pentaflurophenyl substituent(fluorine effect)may play important roles in enhancement of enantioselectivity,that is,Ming-Phos is a multifunctional ligand in this transformation.

关键词： Gold Asymmetric catalysis Fluorine effect Cycloaddition Multifunctional ligand

Promising approach for preparing metallic single-atom catalysts: electrochemical deposition

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Frontiers in Energy 2022年第4期16卷 537-541页

作者： Shuiyun SHEN Lutian ZHAO junliang zhang Institute of Fuel Cells School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Developing energy conversion technologies via electrochemistry will significantly facilitate the largescale utilization of renewable energy,thus helping address issues regarding energy shortage and environmental deterioration.The application of electrochemical energy conversion reactions such as electricity generation and electrolysis is highly dependent on developing efficient electrocatalysts.Metallic electrocatalysts,including pure metals and alloys,possess superior intrinsic activities compared to other materials for various energy-conversion reactions,ascribed to the active d-electrons[1–3].Traditionally,low-coordinated and unsaturated metal atoms have been the most important active sites for catalysis.Thus,over the past few decades,the most popular strategy to improve catalytic activity has been to reduce the particle size from bulk to nanoscale[4,5]as shown in Fig.1.However,only a few atomic layers at the surface of nanoparticles contribute to these catalytic reactions,leading to lower metal utilization[6,7].In addition,several active sites for side reactions exist,which further impede the improvement of selectivity and activity.

关键词： electrochemical preparing metallic

Block copolymer functionalized quartz fibers/cyanate ester wave-transparent laminated composites

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Journal of Materials Science & Technology 2023年第8期139卷 189-197页

作者： Jiani zhang Zheng Liu Muyi Han junliang zhang Yusheng Tang Junwei Gu Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an 710072China

A block copolymer of PDMS-b-PGMA is synthesized by polymerizing glycidyl methacrylate(GMA)via reversible addition-fragmentation chain transfer(RAFT)polymerization applying a polydimethylsiloxane(PDMS)based macro-RAFT agent,which is then performed to functionalize the quartz fibers(QFs@PDMS-b-PGMA)via a simple coating process.Finally,the QFs@PDMS-b-PGMA/bisphenol A dicyanate ester(BADCy)wave-transparent laminated composites are fabricated by high-temperature molding.Nuclear magnetic resonance(NMR)spectroscopy,Fourier transform infrared(FT-IR)spectroscopy and size ex-clusion chromatography(SEC)demonstrate the successful preparation of PDMS-b-PGMA with expected structure.When the molar mass and coating amount of PDMS-b-PGMA are respectively 8100 g/mol and 2.0 wt.%,QFs@PDMS-b-PGMA/BADCy wave-transparent laminated composites present optimal mechan-ical properties and wave-transparent performance.The interlaminar shear strength(ILSS)and flexural strength are 53.6 and 552.0 MPa,respectively.Meanwhile,the dielectric constant and dielectric loss val-ues are 2.61 and 0.0028 at 1 MHz(wave transmittance of 93.8%),showing good stability at different frequencies(102-106 Hz and 8.4-12.4 GHz)and temperatures(25-250℃).

关键词： Bisphenol A dicyanate ester(BADCy)resins Quartz fibers(QFs) Wave-transparent laminated composites Block copolymer