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Decoding the mechanism of P450-catalyzed aromatic hydroxylation:Uncovering the arene oxide pathway and insights into the regioselectivity 被引量:2
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作者 Qun Huang Xuan Zhang +8 位作者 Guangwu Sun Rui-ying Qiu Lan Luo Cuizhen Wang Longwei Gao Bing Gao Bo Chen Binju Wang Jian-bo Wang 《Chinese Journal of Catalysis》 2025年第3期420-430,共11页
P450 enzymes-catalyzed aromatic hydroxylation plays an important role in detoxification,biosynthesis,and potential carcinogenic effect of aromatic compounds.Though it has been explored for decades,the actual process o... P450 enzymes-catalyzed aromatic hydroxylation plays an important role in detoxification,biosynthesis,and potential carcinogenic effect of aromatic compounds.Though it has been explored for decades,the actual process of aromatic hydroxylation and mechanism of regioselectivity catalyzed by cytochrome P450 monooxygenases remained ambiguous.Here,we have resolved these issues.With a stable chiral organofluorine probe,and especially with X-ray data of two isolated arene oxides derivatives,we demonstrate that an arene oxide pathway is definitely involved in P450-catalyzed aromatic hydroxylation.By the capture,isolation,identification and reactivity exploration of the arene 1,2-oxide and arene 2,3-oxide intermediates,together with advanced QM calculations,the mechanism of how two intermediates go to the same product has been elucidated.In addition to the model substrate,we also confirmed that an arene oxide intermediate is involved in the P450-catalyzed hydroxylation pathway of a natural product derivative methyl cinnamate,which indicates that this intermediate appears to be universal in P450-catalyzed aromatic hydroxylation.Our work not only provides the most direct evidence for the arene oxide pathway and new insights into the regioselectivity involved in P450-catalyzed aromatic hydroxylation,but also supplies a new synthetic approach to achieve the dearomatization of aromatic compounds. 展开更多
关键词 Aromatic hydroxylation Cytochrome P450 Arene oxide Regioselectivity DEAROMATIZATION
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Silica coating of quantum dots and their applications in optoelectronic fields 被引量:1
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作者 Siting Cai Xiang Chen +3 位作者 Shuli Wang Xinqin Liao Zhong Chen Yue Lin 《Chinese Chemical Letters》 2025年第6期96-107,共12页
Quantum dots(QDs),a type of nanoscale semiconductor material with unique optical and electrical properties like adjustable emission and high photoluminescence quantum yields,are suitable for applications in optoelectr... Quantum dots(QDs),a type of nanoscale semiconductor material with unique optical and electrical properties like adjustable emission and high photoluminescence quantum yields,are suitable for applications in optoelectronics.However,QDs are typically degraded under humid and high-temperature circumstances,greatly limiting their practical value.Coating the QD surface with an inorganic silica layer is a feasible method for improving stability and endurance in a variety of applications.This paper comprehensively reviews silica coating methodologies on QD surfaces and explores their applications in optoelectronic domains.Firstly,the paper provides mainstream silica coating approaches,which can be divided into two categories:in-situ hydrolysis of silylating reagents on QD surfaces and template techniques for encapsulation QDs.Subsequently,the recent applications of the silica-coated QDs on optoelectronic fields including light-emitting diodes,solar cells,photodetectors were discussed.Finally,it reviews recent advances in silica-coated QD technology and prospects for future applications. 展开更多
关键词 Silica-coating Quantum dots Light-emitting diodes Solar cells PHOTODETECTOR
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Selective hydrogenation of 5-hydroxymethylfurfural triggered by a high Lewis acidic Ni-based transition metal carbide catalyst 被引量:1
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作者 Rulu Huang Jianchun Jiang +4 位作者 Jie Liang Shanyong Wang Yuwei Chen Xianhai Zeng Kui Wang 《Green Energy & Environment》 2025年第3期573-584,共12页
The high-efficiency conversion of biomass resources to biofuels has attracted widespread attention, and the active sites and synergistic effect of catalysts significantly impact their surface arrangement and electroni... The high-efficiency conversion of biomass resources to biofuels has attracted widespread attention, and the active sites and synergistic effect of catalysts significantly impact their surface arrangement and electronic structure. Here, a nickel-based transition metal carbide catalyst(Ni/TMC) with high Lewis acidity was prepared by self-assembly of transition metal carbide(TMC) and nickel, which exhibited excellent performance on synergistic hydrogenation and hydrogenolysis of 5-hydroxymethylfurfural(HMF) into liquid biofuel 2,5-dimethylfuran(DMF).Notably, Ni/WC with the highest Lewis acidity(4728.3 μmol g^(-1)) can achieve 100% conversion of HMF to 97.6% yield of DMF, with a turnover frequency of up to 46.5 h^(-1). The characterization results demonstrate that the rich Lewis acid sites yielded by the synergistic effect between Ni species and TMC are beneficial for the C=O hydrogenation and C–O cleavage, thereby accelerating the process of hydrodeoxygenation(HDO). Besides, a kinetic model for the HDO of HMF to DMF process has been established based on the experimental results, which elucidated a significant correlation between the measured and the predicted data(R^(2)> 0.97). Corresponding to the adsorption configuration of Ni/WC and substrate determined by in-situ FTIR characterization, this study provides a novel insight into the selective conversion of HMF process for functional biofuel and bio-chemicals. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL Lewis acid Synergistic effect HYDRODEOXYGENATION 2 5-Dimethylfuran
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Crevice corrosion of reinforcing steel in carbonated simulated concrete pore solutions contaminated by chloride 被引量:1
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作者 Peng-peng Wu Yuan-pei Gong +3 位作者 Shao-hua Zhang Yue-zhong Zhang Bao-sheng Liu Guang-ling Song 《Journal of Iron and Steel Research International》 2025年第1期293-311,共19页
The crevice corrosion of the reinforcing steel in the carbonated simulated concrete pore solutions(SCPSs)containing 0.04 mol/L chloride was investigated.In comparison,the steel without crevice covered on its surface w... The crevice corrosion of the reinforcing steel in the carbonated simulated concrete pore solutions(SCPSs)containing 0.04 mol/L chloride was investigated.In comparison,the steel without crevice covered on its surface was also studied.Results showed that the crevice corrosion in the uncarbonated SCPS was not triggered and the steel remained passivity by suppressing the anodic dissolution in the crevice interior.As SCPS was carbonated to have pH values of 10.5 and 11.5,the crevice corrosion was easier to be activated than the widely reported pitting corrosion owing to the rapid oxygen depletion within the crevice,but the crevice corrosion damage might be alleviated to a certain extent due to the relative compact surface film formed inside the crevice.The further carbonation led to the activation dissolution of both the crevice interior and exterior,causing the more serious corrosion damage.Corrosion process of the crevice corrosion was systematically analyzed by combining the electrochemical measurement results and Evens polarization diagram. 展开更多
关键词 Crevice corrosion Reinforcing steel CARBONATION Electrochemical test RUST Evens polarization diagram
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Recent advances of photolithography patterning of quantum dots for micro-display applications 被引量:1
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作者 Xuemin Kong Xiaotong Fan +6 位作者 Yuhui Wang Yunshu Luo Yihang Chen Tingzhu Wu Zhong Chen Yue Lin Shuli Wang 《Nano Materials Science》 2025年第1期49-64,共16页
The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and... The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and mixed reality applications.Alongside the controlled synthesis of high-performance QDs,a reliable QD patterning technology is crucial in overcoming this challenge.Among the various methods available,photolithography-based patterning technologies show great potentials in producing ultra-fine QD patterns at micron scale.This review article presents the recent advancements in the field of QD patterning using photolithography techniques and explores their applications in micro-display technology.Firstly,we discuss QD patterning through photolithography techniques employing photoresist(PR),which falls into two categories:PRassisted photolithography and photolithography of QDPR.Subsequently,direct photolithography techniques based on photo-induced crosslinking of photosensitive groups and photo-induced ligand cleavage mechanisms are thoroughly reviewed.Meanwhile,we assess the performance of QD arrays fabricated using these photolithography techniques and their integration into QD light emitting diode display devices as well as color conversionbased micro light emitting diode display devices.Lastly,we summarize the most recent developments in this field and outline future prospects. 展开更多
关键词 Quantum dot PHOTOLITHOGRAPHY Patterning technology Micro-display
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Surface defect engineering of ZnCoS in ZnCdS with twin crystal structure for visible-light-driven H_(2) production coupled with benzyl alcohol oxidation 被引量:1
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作者 Tan Ji Siang Peipei Zhang +1 位作者 Binghui Chen Wee-Jun Ong 《Chinese Journal of Catalysis》 2025年第2期84-98,共15页
Photoredox dual reaction of organic synthesis and H2 evolution opens up a novel pathway for collaboratively generating clean fuels and high-quality chemicals,providing a more effective approach of solar energy convers... Photoredox dual reaction of organic synthesis and H2 evolution opens up a novel pathway for collaboratively generating clean fuels and high-quality chemicals,providing a more effective approach of solar energy conversion.Herein,a surface defect-engineered ZnCoS/ZnCdS heterostructure with zinc blende(ZB)/wurtzite(WZ)phase junctions is synthesized for photocatalytic cooperative coupling of benzaldehyde(BAD)and H_(2) production.This surface defect-engineered ZnCoS/ZnCdS heterostructure elaborately integrates the mixed phase junction advantage of ZnCdS semiconductor and the cocatalytic function of ZnCoS possessing Zn(VZn-ZnCoS/ZnCdS)or S vacancies(VS-ZnCoS/ZnCdS).The optimum VS-ZnCoS/ZnCdS simultaneously exhibits a superior H2 production rate of 14.23 mmol h^(-1) g^(-1) accompanied with BAD formation rate of 12.29 mmol h^(-1) g^(-1) under visible-light irradiation,which is approximately two-fold greater than that of pristine ZnCdS.Under simulated sunlight irradiation(AM 1.5),VS-ZnCoS/ZnCdS achieves H2 evolution(27.43 mmol gcat^(-1) h^(-1))with 0.52%of STH efficiency,accompany with 26.31 mmol gcat^(-1) h^(-1) of BAD formation rate.The underlying solar-driven mechanism is elucidated by a series of in-situ characterization and control experiments,which reveals the synergistic effect of interfacial ZB/WZ phase junctions in ZnCdS and S vacancies of ZnCoS on enhancement of the photoredox dual reaction.The VS-ZnCoS/ZnCdS follows a predominant oxygen-centered radical integrating with carbon-centered radical pathways for BAD formation and a simultaneous electron-driven proton reduction for H_(2) production.Interestingly,the nature of surface vacancies not only facilitates the separation of photoinduced charge carriers but also able to selectively adjust the mechanism pathway for BAD production via tuning the oxygen-centered radical and carbon-centered radical formation. 展开更多
关键词 Photoredoxdual reaction Aromatic alcohol conversion Surface vacancy Organic synthesis H_(2)production
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Advances in component and operation optimization of solid oxide electrolysis cell 被引量:4
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作者 Xiaoxin Zhang Bo Liu +5 位作者 Yanling Yang Jianhui Li Jian Li Yingru Zhao Lichao Jia Yifei Sun 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第5期155-164,共10页
Considering the earth powered by intermittent renewable energy in the coming future,solid oxide electrolysis cell(SOEC)will play an indispensable role in efficient energy conversion and storage on demand.The thermolyt... Considering the earth powered by intermittent renewable energy in the coming future,solid oxide electrolysis cell(SOEC)will play an indispensable role in efficient energy conversion and storage on demand.The thermolytic and kinetic merits grant SOEC a bright potential to be directly integrated with electrical grid and downstream chemical synthesis process.Meanwhile,the scientific community are still endeavoring to pursue the SOEC assembled with better materials and operated at a more energy-efficient way.In this review article,at cell level,we focus on the recent development of electrolyte,cathode,anode and buffer layer materials for both steam and CO_(2)electrolysis.On the other hand,we also discuss the next generation SOEC operated with the assistant of other fuels to further reduce the energy consumption and enhance the productivity of the electrolyzer.And stack level,the sealant,interconnect and stack operation strategies are collectively covered.Finally,the challenges and future research direction in SOECs are included. 展开更多
关键词 Solid oxide electrolysis cell Fuel assistant STACK Operation condition ANODE CATHODE
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A state-of-the-art review on passivation and biofouling of Ti and its alloys in marine environments 被引量:21
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作者 Shaokun Yan Guang-Ling Song +6 位作者 Zhengxian Li Haonan Wang Dajiang Zheng Fuyong Cao Miroslava Horynova Matthew S.Dargusch Lian Z-hou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第3期421-435,共15页
High strength-to-weight ratio, commendable biocompatibility and excellent corrosion resistance make Ti alloys widely applicable in aerospace, medical and marine industries. However, these alloys suffer from serious bi... High strength-to-weight ratio, commendable biocompatibility and excellent corrosion resistance make Ti alloys widely applicable in aerospace, medical and marine industries. However, these alloys suffer from serious biofouling, and may become vulnerable to corrosion attack under some extreme marine conditions. The passivating and biofouling performance of Ti alloys can be attributed to their compact, stable and protective films. This paper comprehensively reviews the passivating and biofouling behavior, as well as their mechanisms, for typical Ti alloys in various marine environments. This review aims to help extend applications of Ti alloys in extremely harsh marine conditions. 展开更多
关键词 Ti alloy Passivity Biofouling
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Correlating the electronic structure of perovskite La_(1-x)SrxCoO_(3) with activity for the oxygen evolution reaction:The critical role of Co 3d hole state 被引量:2
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作者 Zechao Shen Mei Qu +8 位作者 Jueli Shi Freddy E.Oropeza Victor A.de la Peña O’Shea Giulio Gorni C.M.Tian Jan P.Hofmann Jun Cheng Jun Li Kelvin H.L.Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第2期637-645,共9页
Perovskite LaCoO_(3) is being increasingly explored as an effective low-cost electrocatalyst for the oxygen evolution reaction(OER).Sr doping in LaCoO_(3)(La1-xSrxCoO_(3))has been found to substantially increase its c... Perovskite LaCoO_(3) is being increasingly explored as an effective low-cost electrocatalyst for the oxygen evolution reaction(OER).Sr doping in LaCoO_(3)(La1-xSrxCoO_(3))has been found to substantially increase its catalytic activity.In this work,we report a detailed study on the evolution of the electronic structure of La1-xSrxCoO_(3) with 0≤x≤1 and its correlation with electrocatalytic activity for the OER.A combination of X-ray photoemission spectroscopy(XPS)and X-ray absorption spectroscopy(XAS)was used to unravel the electronic density of states(DOS)near the Fermi level(EF),which provide insights into the key electronic structure features for the enhanced OER catalytic activity.Detailed analysis on the Co L-edge XAS suggest that LaCoO_(3) has a low spin state with t_(2g)^(6) e_(g)^(0) configuration at room temperature.This implies that the high OER catalytic activity of LaCoO_(3) should not be rationalized by the occupancy of eg=1 descriptor.Substituting Sr^(2+) for La^(3+) in LaCoO_(3) induces Co4+oxidation states and effectively dopes hole states into the top of valence band.A semiconductor-to-metal transition is observed for x>0.2,due to the holeinduced electronic DOS at the EF and increased hybridization between Co 3 d and O 2 p.Such an electronic modulation enhances the surface adsorption of the*OH intermediate and reduces the energy barrier for interfacial charge transfer,thus improving the OER catalytic activity in La_(1-x)Sr_(x)CoO_(3).In addition,we found that the La_(1-x)Sr_(x)CoO_(3) surface undergoes amorphization after certain period of OER measurement,leading to a partial deactivation of the electrocatalyst.High Sr doping levels accelerated the amorphization process. 展开更多
关键词 Perovskite oxide Oxygen evolution COBALT Electronic structure
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Solid and Solution Structural Studies of Dimeric and Tetrameric Molybdenum(VI) Malate Complexes 被引量:1
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作者 张荣华 周朝晖 万惠霖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第8期919-926,共8页
Reactions of potassium molybdate with racemic malic acid (H3mal = C4H6O5) result in the isolation of two mesomeric molybdenum malate complexes K8[(MoO2)2O(R-mal)2][(MoO2)2O(Smal)2]-4H2O 1 and (Him)2K6[(M... Reactions of potassium molybdate with racemic malic acid (H3mal = C4H6O5) result in the isolation of two mesomeric molybdenum malate complexes K8[(MoO2)2O(R-mal)2][(MoO2)2O(Smal)2]-4H2O 1 and (Him)2K6[(MoO2)4O3(R-mal)2][(MoOE)4O3(S-mal)2]-8H2O 2. Complex 1 belongs to the monoclinic system, space group C2/c with a = 14.8637(3), b = 6.9544(1), c = 19.6783(5)A, β = 100.081(2)°, V = 2002.70(7) A^3, Mr = 1452.88, Z = 2, F(000) = 1416, T = 173 K, Dc = 2.409 g/cm3, fl(MoKa') = 2.167, R = 0.0283 and wR = 0.0733.2 is of triclinic system, space group P1^- with a = 8.7707(2), b = 9.3310(3), c = 17.9093(7)A, α= 83.781(3), β = 85.626(2), y= 84.822(2)°, V = 1447.84(8)A^3, Mr = 2160.68, Z = 1, F(000) = 1048, T = 173 K, Dc = 2.478 g/cm^3,μ(MoKα) = 2.230, R = 0.0234 and wR = 0.0584.1 is the first isolated dinuclear molybdenum(VI) malato complex in 1:1 molar ratio. The molybdenum atoms in the two complexes are six-coordinated in an approximately octahedral geometry. Two malates coordinate tridentately with the Mo atom via their α-alkoxy, α-carboxy and α-carboxy groups in 1 and 2. β-Carboxy group in 2 further links with the other two Mo atoms to give a tetrameric unit. The solution ^1H and ^13C NMR spectra indicate that dimeric malate molybdenum in 1 dissociates partly in solution and exists in an equilibrium with tetrameric species, while 2 is stable and retains its tetrameric structure without any dissociation. 展开更多
关键词 molybdate(VI) MALATE NITROGENASE crystal structure NMR
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Promote the conductivity of solid polymer electrolyte at room temperature by constructing a dual range ionic conduction path 被引量:1
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作者 Ruiyang Li Haiming Hua +4 位作者 Yuejing Zeng Jin Yang Zhiqiang Chen Peng Zhang Jinbao Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期395-403,I0011,共10页
Poly(ethylene oxide)(PEO)is a classic matrix model for solid polymer electrolyte which can not only dissociate lithium-ions(Li^(+)),but also can conduct Li^(+) through segmental motion in long-range.However,the crysta... Poly(ethylene oxide)(PEO)is a classic matrix model for solid polymer electrolyte which can not only dissociate lithium-ions(Li^(+)),but also can conduct Li^(+) through segmental motion in long-range.However,the crystal aggregation state of PEO restricts the conduction of Li^(+) especially at room temperature.In this work,an amorphous polymer electrolyte with ethylene oxide(EO)and propylene oxide(PO)block structure(B-PEG@DMC)synthesized by the transesterification is firstly obtained,showing an ionic conductivity value of 1.1×10^(5) S/cm at room temperature(25℃).According to the molecular dynamics(MD)simulation,the PO segments would lead to an inconsecutive and hampered conduction of Li^(+),which is not beneficial to the short range conduction of Li^(+).Thus the effect of transformation of aggregation state on the improveme nt of ionic conductivity is not eno ugh,it is n ecessary to further consider the differe nt coupled behaviours of EO and PO segments with Li^(+).In this way,we blend this amorphous polymer(B-PEG@DMC)with PEO to obtain a dual range ionic conductive solid polymer electrolyte(D-SPE)with further improved ionic conductivity promoted by constructing a dual range fast ionic conduction,which eventually shows a further improved ionic conductivity value of 2.3×10^(5) S/cm at room temperature. 展开更多
关键词 Solid polymer electrolyte Amorphous polymer Ionic conductivity Room temperature Arrhenius equation
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Development Trends and Priority Research Fields of Electrochemical Discipline in the 15th Five Year Plan Period
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作者 Lin Zhuang Wen-Bin Cai +36 位作者 Heng-Xing Ji Qing Li Gong-Wei Wang Sen Xin Qing Zhao Fang-Yi Cheng Yu-Guo Guo Lan-Qun Mao Yang Tian Fei Wu Li-Min Zhang Yan Xiang Jin-Song Hu Rui Cao Li Xiao Hua-Bing Tao Wei Xing Dong-Ping Zhan Hong-Gang Liao Mei-Ling Xiao Bin Ren Zhang-Quan Peng Rui Wen Xiang Wang Yue-Feng Song Hou-Fu Lv Bao-Yu Xia Guo-Xiong Wang Jun Cheng Zhi-Pan Liu Min Zhou Bing Huang Cun-Pu Li Yu-Qin Zou Shuang-Yin Wang Hai-Bo Lin Zi-Dong Wei 《电化学(中英文)》 北大核心 2025年第10期84-115,共32页
In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteent... In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteenth FiveYear (20262030) Development Plan for Electrochemistry held in Xiamen on 29 August, 2025-the culminating year of the Fourteenth Five-Year (2021-2025) Development Plan. More than forty leading experts in the field of electrochemistry participated with spanning nine thematic fronts: Interfacial Electrocatalysis, Interfacial Electrochemistry for Energy Storage, Bioelectrochemistry, Electrochemistry of Hydrogen Energy, Electrochemical Micro-/Nano-Manufacturing, Operando Electrochemical Characterization, Electro-Thermal Coupling Catalysis, Theoretical and Computational Electrochemistry,and Electrochemical Synthesis. The forum assembled China's foremost electrochemical expertise to blueprint high-quality disciplinary growth for the coming five-year period, thereby serving overarching national strategic needs and sharpening the international competitiveness of Chinese electrochemistry.This paper is presented to highlight the strategic needs and priority areas for the next five years (2026-2030) based on this symposium. The development status of basic research and applied basic research in China's electrochemistry field is systematically reviewed. The in-depth analyses of the existing problems and key challenges in the research and development of electrochemistry related fields are outlined, and the frontier research areas and development trends in the next 5-10 years by integrating national major strategic needs are discussed, which will further promote the academic community to reach a clearer consensus. The proposed strategic roadmap is intended to accelerate a sharpened community consensus, propel the discipline toward high-quality advancement, and furnish a critical reference for building China into a world-leading science and technology power. 展开更多
关键词 energy storage ELECTROCHEMISTRY strategic symposium chemical sciences interfacial electrocatalysis hydrogen energy BIOELECTROCHEMISTRY electrochemical micro nano manufacturing
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A new horizontal in C1 chemistry: Highly selective conversion of syngas to light olefins by a novel OX-ZEO process 被引量:1
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作者 Ye Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第2期167-168,共2页
The most challenging goal of C1 chemistry is the control of C–C coupling to produce chemicals or fuels from C1 feedstocks,in particular syngas(H2/CO),which can be derived from various carbon resources such as coal,... The most challenging goal of C1 chemistry is the control of C–C coupling to produce chemicals or fuels from C1 feedstocks,in particular syngas(H2/CO),which can be derived from various carbon resources such as coal,natural gas or shale gas,and biomass. 展开更多
关键词 challenging propylene chemicals shale Highly biomass selectivity hydrocarbons currently naphtha
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Photocontrolled Solution[2+2]Polymerization of p-Phenylenediacrylate and Depolymerization
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作者 Miao-Yan Yi Yu Jiang Sai-Hu Liao 《Chinese Journal of Polymer Science》 2025年第11期1973-1980,I0007,共9页
The[2+2]photopolymerization of bisolefinic monomers is an important method for the synthesis of polymeric materials.However,these processes are usually carried out in solid states under the irradiation of high-energy ... The[2+2]photopolymerization of bisolefinic monomers is an important method for the synthesis of polymeric materials.However,these processes are usually carried out in solid states under the irradiation of high-energy UV light,while the corresponding[2+2]polymerization in solution has proved to be inefficient due to the lack of preassembly of the monomers.Herein,we demonstrate that the[2+2]polymerization of p-phenylenediacrylate monomers can be achieved in solution under visible light by employing energy transfer catalysis with 2,2'-methoxythioxanthone as a photocatalyst.Because no preassembly is required,this solution polymerization is applicable to p-phenylenediacrylate monomers with different ester groups,affording a series of cyclobutane-imbedded full-carbon chain polymers with high thermal stability,good solubility,and processibility.In addition,by virtue of the reversibility of the photo[2+2]cycloaddition,this[2+2]photopolymerization product can also undergo depolymerization to lower molecular weight polymers,suggesting the potential of this class of photopolymerization in the development of closed-loop chemical recyclable polymers. 展开更多
关键词 [2+2]Polymerization PHOTOPOLYMERIZATION p-Phenylenediacrylates ORGANOCATALYSIS DEPOLYMERIZATION
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An Efficient Deep Learning Framework for Revealing the Evolution of Characterization Methods in Nanoscience
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作者 Hui‑Cong Duan Long‑Xing Lin +6 位作者 Ji‑Chun Wang Tong‑Ruo Diao Sheng‑Jie Qiu Bi‑Jun Geng Jia Shi Shu Hu Yang Yang 《Nano-Micro Letters》 2025年第11期755-768,共14页
Text mining has emerged as a powerful strategy for extracting domain knowledge structure from large amounts of text data.To date,most text mining methods are restricted to specific literature information,resulting in ... Text mining has emerged as a powerful strategy for extracting domain knowledge structure from large amounts of text data.To date,most text mining methods are restricted to specific literature information,resulting in incomplete knowledge graphs.Here,we report a method that combines citation analysis with topic modeling to describe the hidden development patterns in the history of science.Leveraging this method,we construct a knowledge graph in the field of Raman spectroscopy.The traditional Latent DirichletAllocation model is chosen as the baseline model for comparison to validate the performance of our model.Our method improves the topic coherence with a minimum growth rate of 100%compared to the traditional text mining method.It outperforms the traditional text mining method on the diversity,and its growth rate ranges from 0 to 126%.The results show the effectiveness of rule-based tokenizer we designed in solving the word tokenizer problem caused by entity naming rules in the field of chemistry.It is versatile in revealing the distribution of topics,establishing the similarity and inheritance relationships,and identifying the important moments in the history of Raman spectroscopy.Our work provides a comprehensive tool for the science of science research and promises to offer new insights into the historical survey and development forecast of a research field. 展开更多
关键词 NANOSTRUCTURE Deep learning DATA-DRIVEN RAMAN Nanoscience
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Spontaneous increasing of sensitivity and resolution in parahydrogen-induced hyperpolarization by RASER
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作者 Zeyu Zheng Qiwei Peng +2 位作者 Huijun Sun Xinchang Wang Zhong Chen 《Magnetic Resonance Letters》 2025年第1期1-11,共11页
Enhancing the sensitivity of nuclear magnetic resonance(NMR)technology has been the focus of NMR research for decades,which offers the potential to significantly expand its applications in chemistry,biology,and medica... Enhancing the sensitivity of nuclear magnetic resonance(NMR)technology has been the focus of NMR research for decades,which offers the potential to significantly expand its applications in chemistry,biology,and medical imaging.Parahydrogen-induced polarization(PHIP)emerges as a cost-effective approach to substantially enhance the sensitivity of NMR.Nevertheless,the amplification of the ^(1)H signal in PHIP is susceptible to interference from the thermal polarization state ^(1)H NMR signal.Employing RASER(radiofrequency amplification by stimulated emission of radiation)proves effective in mitigating such interference,which can reduce the linewidth and increase the sensitivity at the same time.In this work,we utilized PHIP and RASER to enhance the signal-to-noise ratio(SNR)of a series of biocompatible alkynyl organic acid molecules.The alkynyl acid with the highest enhancement factor was first identified through PASADENA(parahydrogen and synthesis allow dramatically enhanced nuclear alignment)experiments.Subsequently,RASER experiments were carried out through hyperpolarization of 5-hexynoic acid,exploring its signal characteristics under varying flow rates and pressures.The SNR of proton signals of 5-hexynoic acid surpassed 150,000,an 18.62-fold improvement compared with traditional hyperpolarized signals in PASADENA,and a markedly narrowed linewidth of 0.06 Hz. 展开更多
关键词 Nuclear magnetic resonance Parahydrogen-induced polarization PASADENA RASER Alkynyl acid
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Enhancing long-term cycling stability of spinel LiNi_(0.5)Mn_(1.5)O_(4)cathode via ultrathin ZrO_(2)coating layer
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作者 Jie MEI Qi-xiang XU +5 位作者 Yuan-zhi CHEN Gui-yang GAO Wan-jie XU Qing-shui XIE Lai-seng WANG Dong-liang PENG 《Transactions of Nonferrous Metals Society of China》 2025年第12期4217-4229,共13页
Spinel LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)cathode draws significant attention in the field of energy storage due to its unique voltage plateau.To further enhance the long-term electrochemical stability of LNMO,the LNMO cath... Spinel LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)cathode draws significant attention in the field of energy storage due to its unique voltage plateau.To further enhance the long-term electrochemical stability of LNMO,the LNMO cathode covered with an ultrathin ZrO_(2)layer was prepared through atomic layer deposition(ALD).It is found that the LNMO cathode deposited with 20 layers of ZrO_(2)(LNMOZ20)exhibits the best electrochemical performance,achieving a high discharge capacity of 117.1 mA·h/g,with a capacity retention of 87.4%after 600 cycles at a current density of 1C.Furthermore,even at higher current densities of 5C and 10C,the LNMOZ20 electrode still demonstrates excellent stability with discharge capacities reaching 111.7 and 103.6 mA·h/g,and capacity retentions maintaining at 81.0%and 101.4%after 2000 cycles,respectively.This study highlights that the incorporation of an ultrathin ZrO_(2)layer by ALD is an effective strategy for enhancing the long-term cycling stability of LNMO cathodes. 展开更多
关键词 spinel LiNi_(0.5)Mn_(1.5)O_(4) ZrO_(2)coating high-voltage cathode atomic layer deposition cathode electrolyte interphase film
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Elevating dual-redox photocatalysis with p-n junction:Hydrangea-like Zn_(3)In_(2)S_(6)nanoflowers coupled hexagonal Co_(3)O_(4)for cooperative hydrogen and benzaldehyde production
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作者 Xin-Quan Tan Grayson Zhi Sheng Ling +3 位作者 Tan Ji Siang Xianhai Zeng Abdul Rahman Mohamed Wee-Jun Ong 《Nano Materials Science》 2025年第2期169-179,共11页
Despite advances in photocatalytic half-reduction reactions,challenges remain in effectively utilizing electron-hole pairs in concurrent redox processes.The present study involved the construction of a p-n junction Co... Despite advances in photocatalytic half-reduction reactions,challenges remain in effectively utilizing electron-hole pairs in concurrent redox processes.The present study involved the construction of a p-n junction Co_(3)O_(4)/Zn_(3)In_(2)S_(6)(CoZ)hybrid with a complementary band edge potential.The photocatalyst formed by the 2D assembled-nanostructure portrayed an optimal yield of 13.8(H_(2))and 13.1(benzaldehyde)mmol g^(-1)h^(-1)when exposed to light(λ>420 nm),surpassing 1%Pt-added ZIS(12.4(H_(2))and 10.71(benzaldehyde)mmol g^(-1)h^(-1)).Around 95%of the electron-hole utilization rate was achieved.The solar-to-hydrogen(STH)and apparent quantum yield(AQY)values of 0.466%and 4.96%(420nm)achieved by this system in the absence of sacrificial agents exceeded those of previous works.The exceptional performance was mostly ascribed to the synergistic development of adjoining p-n heterojunctions and the built-in electric field for effective charge separation.Moreover,scavenger studies elucidated the intricate mechanistic enigma of the dual-redox process,in which benzaldehyde was produced via O-H activation and subsequent C-H cleavage of benzyl alcohol over CoZ hybrids.Furthermore,the widespread use of the optimal 1-CoZ composites was confirmed in multiple photoredox systems.This work presents an innovative perspective on the construction of dual-functioning p-n heterojunctions for practical photoredox applications. 展开更多
关键词 Hexagonal Co_(3)O_(4) Zn_(3)In_(2)S_(6)nanoflowers Dual photoredox reaction Hydrogen evolution Benzyl alcohol oxidation p-n heterojunction
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Enhanced electrochemical performance of lithium-rich layered oxide materials: Exploring advanced coating strategies
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作者 Bing Jiang Gang Zou +8 位作者 Bi Luo Yan Guo Jingru Li Wendi Zhang Qianxiao Fan Lehao Liu Lihua Chu Qiaobao Zhang Meicheng Li 《Chinese Chemical Letters》 2025年第4期479-485,共7页
In the field of lithium-ion battery cathode materials, lithium-rich layered oxide materials have garnered significant attention due to their exceptional discharge specific capacity and high operating voltage. However,... In the field of lithium-ion battery cathode materials, lithium-rich layered oxide materials have garnered significant attention due to their exceptional discharge specific capacity and high operating voltage. However, their limitations in terms of cycling stability and rate capability remain major impediments to their wider application. In this study, an innovative approach was employed by simultaneously utilizing the acidic and oxidative properties of phosphomolybdic acid to generate a spinel structure and in-situ coating of a conductive polymer(polypyrrole) on the surface of lithium-rich layered oxide materials. This strategy aimed to mitigate structural degradation during charge-discharge cycles, enhance the ionic/electronic conductivity, and suppress side reactions. Experimental results demonstrated that after 200 cycles at a current density of 1 C, the modified sample exhibited a discharge specific capacity of 193.4 m Ah/g, with an improved capacity retention rate of 83.3% and a minimal voltage decay of only 0.27 V. These findings provide compelling support for the development and application of next-generation high-performance lithium-ion batteries. 展开更多
关键词 Lithium-ion battery Lithium-rich layered oxide materials Spinel phase Conductive polymer COATING
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Investigation of water structure and proton transfer within confined graphene by ab initio molecule dynamics and multiscale data analysis
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作者 Heng-Su Liu Xi-Ming Zhang +2 位作者 Ge-Hao Liang Shisheng Zheng Jian-Feng Li 《Chinese Journal of Structural Chemistry》 2025年第6期41-49,共9页
The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there r... The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there remains a lack of consensus on fundamental properties such as diffusion behavior and the nature of hydrogen bonding in confined environments.In this work,we investigated the influence of confinement on proton transfer in water confined within graphene sheets at various spacings by ab initio molecule dynamic and multiscale analysis with time evolution of structural properties,graph theory and persistent homology.We found that reducing the graphene interlayer distance while maintaining water density close to that of bulk water leads to a decrease in proton transfer frequency.In contrast,reducing the interlayer distance without maintaining bulk-like water density results in an increase in proton transfer frequency.This difference is mainly due to the confinement conditions:when density is unchanged,the hydrogen bond network remains similar with significant layering,while compressive stress that increases density leads to a more planar hydrogen bond network,promoting faster proton transfer.Our findings elucidate the complex relationship between confinement and proton transfer dynamics,with implications for understanding proton transport in confined environments,relevant to energy storage and material design. 展开更多
关键词 Molecular dynamics GRAPHENE Confined water Graph theory Persistent homology
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