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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong Liu College of Chemistry and materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

High-selectivity electroreduction of low-concentration CO2 with large concentration fluctuation

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Science China Chemistry 2025年

作者： Mengyu Qi Yanbin Ma Chao Zhang Bingwei Li Xueqing Yang Zhaolin Shi Simeng Liu Changhua An Jiqing Jiao Tongbu Lu MOE International Joint Laboratory of materials Microstructure Analysis and Testing CenterInstitute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of Technology Key Laboratory of Advanced Energy materials Chemistry (Ministry of Education) Nankai University

Electrochemical CO2reduction reaction（CO2RR） has been regarded as one of the most promising solutions to achieving “zero carbon emission”. In most of the CO2RR-related studies, high-purity CO2has been employed as the feed gas; however, in practice, CO2is generally emitted in low concentrations, so it is of great significance to realize high-selectivity electroreduction of low-concentration CO2with large concentration fluctuation. In this work, we constructed a dual-active-site catalyst and successfully achieved CO2local enrichment and conversion for low-concentration CO2. Operando experiments reveal that the catalyst has one type of site for activating CO2and one type of site for binding the reaction intermediates. The dual-active-site catalyst displays a selectivity for formic acid consistently above 97% over a broad potential window（from-0.9 to-1.6 V ***）. Even when fed with a low-concentration CO2stream（volume ratio from 50% down to 10%）, the dual-active-site catalyst could display high activity and selectivity（>91%）. In particular, the selectivity is still above 85% when the CO2volume ratio is as low as 5%. This work offers a feasible route for converting low-concentration CO2via a synergistic effect for dual-active-site catalysts.

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Spin-modulated near-infrared-Ⅰ emission in a xanthene-decorated Fe(Ⅱ) spin-crossover complex

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Science China Chemistry 2025年

作者： Cheng Yi Duyong Chen Shihui Zhang Rui Cai Chunying Duan Yinshan Meng Tao Liu State Key Laboratory of Fine Chemicals Frontier Science Center for Smart Materials and Chemical Engineering School of Chemical Engineering Dalian University of Technology Instrumental analysis center Dalian University of Technology School of Chemistry Dalian University of Technology Liaoning Binhai Laboratory

Molecular materials showing synergetic coupling of near-infrared （NIR） fluorescence and spin-crossover （SCO） are promisingly applicable in in-vivo bioimaging,temperature sensing,and spintronic *** the related study faces formidable *** this work we graft the NIR fluorophore xanthene onto the dipyridyl substituted triazole ligand and construct a new Febased SCO material,{FeⅡ（ddxc-abpt）2[N（CN）2]2}(1,ddxc-abpt:（E）-4-(((3,5-di（pyridin-2-yl）-4H-1,2,4-triazol-4-yl)imino)methyl)-N,N-diethyl-2,3-dihydro-1H-xanthen-6-amine).Magnetic studies indicate that compound 1 exhibits thermally induced SCO property in both the solid and solution ***-temperature fluorescence emission spectra reveal a remarkable 7-fold increase in photoluminescence intensity upon the transition from the low-spin state at 110 K to the high-spin state at 280 K,which is the record of all reported coupled fluorescence-SCO ***-temperature ultraviolet-visible （UV-Vis）absorption spectra show a significant change in absorption intensity within the fluorescence emission window,consistent with the F?rster resonance energy transfer （FRET） ***-dependent density functional theory （TD-DFT） calculations demonstrate that the strong coupling is attributed to disrupted energy transfer between the xanthene fluorophore and high-spin *** work provides a feasible approach for expanding the synergetic SCO-fluorescence materials to the NIR-Iwavelength region,and hopefully contributes to the applications of tunable NIR-SCO molecule-based sensors and devices.

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Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao Hang Ma Conghui Zhang Yongxin Yang Shuyuan Yu Haiye Zhu Yongjiang Sun Hong Guo School of materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

维普期刊数据库

Simulation and analysis of the long-term impacts of 1.5°C global climate pledges on China's land systems

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Science China Earth Sciences 2025年

作者： Jiaying LV Changqing SONG Yifan GAO Sijing YE Peichao GAO State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University center for GeoData and analysis Beijing Normal University

Global warming has become a shared issue for humanity. At the 26th Conference of the Parties to the United Nations Framework Convention on Climate Change in 2021, participating countries reached climate pledges aimed at making more proactive contributions to limit the global average temperature rise within 1.5°C by 2100. Land system changes are significant responses of land to climate change. As one of the contracting parties, China has proposed climate targets such as carbon peaking and carbon neutrality goals in recent years to support the global pledges of limiting global warming to1.5°C, which will profoundly impact China's future land system changes. This study focuses on China as the study area,produces data with a thematic resolution of 27 types of land systems, integrates the output of various land types by the Global Change Assessment Model(GCAM) into four categories of land service demand, and combines these with the improved CLUMondo model to simulate China's land system changes in 2100 under a 1.5°C global warming scenario and a reference scenario without updated emission reduction measures. The conclusions of this study are as follows:(1) The method of integrating the GCAM and improved CLUMondo model demonstrates high validation accuracy in simulating China's land system changes, effectively predicting the changes.(2) Under the 1.5°C global warming scenario, the quality of ecosystems related to mountains, water, forests, farmland, lakes, and grasslands in China improved. The areas of shrubland, wetland, and forest are projected to increase by 185%, 79%, and 33%, respectively, with low-density shrubland, high-density wetland, and high-density forest showing the most significant increases.(3) Compared with the reference scenario, the 1.5°C climate pledges drive greater changes in future land systems, with wetland and forest area growth levels exceeding those of the reference scenario by 20% and 10%, respectively. Notably, the changes in cropland, grasslan

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Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 20-38页

作者： Qinjin Dai Xuefeng Liu Xin Ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation center for materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

维普期刊数据库

Weak KAM theory for two classes of almost periodic Hamiltonian systems

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Science China Mathematics 2025年

作者： Xun Niu Kaizhi Wang Yong Li School of Mathematics and Statistics Center for Mathematics and Interdisciplinary SciencesNortheast Normal University School of Mathematical Sciences Shanghai Frontier Science Center of Modern Analysis (CMA-Shanghai)Shanghai Jiao Tong University Institute of Mathematics Jilin University

The purpose of this paper is to investigate the dynamics of Bohr almost periodic and Levitan almost periodic Hamiltonian systems via the weak KAM theory. We obtain minimal measures and weak KAM solutions in both cases. The weak KAM solution is a weak solution to the Hamilton-Jacobi equation, which formally transforms the original Hamiltonian systems into an integrable one. Consequently, we get the existence of an invariant torus in the aforementioned weak sense.

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Encapsulating perovskite quantum dots into 3D COF for visible light-driven CO2 reduction

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Science China Chemistry 2025年

作者： Xinxin Wang Yucheng Jin Xiya Yang Qingyu Luan Tianyu Wang Dongdong Qi Kang Wang Jianzhuang Jiang College of Chemistry and materials Science Anhui Normal University Beijing Advanced Innovation center for materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of Chemistry and Chemical Engineering School of Chemistry and Biological EngineeringUniversity of Science and Technology Beijing

Lead halide perovskite quantum dots（LHP QDs） have been revealed to possess great potential in photocatalytic applications including CO2reduction, which however suffer from poor stability. Herein, a high crystalline hydrazine-linked three-dimensional（3D） covalent organic framework, USTB-17, was fabricated from the reaction between 12-connected building block and 4-connected 3,5,7-tetrakis（4-aldophenyl）-adamantane. Post-modification with Ni2+affords the metallic framework USTB-17（Ni）followed by sequential deposition of the CH3NH2PbI3（MAPbI3） perovskite QDs into its pores, generating the USTB-17（Ni）@MAPbI3composite. Powder X-ray diffraction analysis together with theoretical simulations and transmission electron microscopy discloses the crystalline nature of USTB-17, USTB-17（Ni）, and USTB-17（Ni）@MAPbI3with an unprecedented noninterpenetrated hpt topology. The close contact of QDs inside the COF pores with the Ni catalytic site locating at the pore surface of COF allows a rapid transfer of the photogenerated electrons in QDs to the Ni catalytic sites, enhancing the photocatalytic activity for CO2reduction. This endows USTB-17（Ni）@MAPbI3with efficient photocatalysis performance for photocatalytic CO2reduction with CO generation rate of 365 μmol g-1h-1and CO selectivity up to 96% under visible-light irradiation, 7 times higher than that of USTB-17（Ni）. After four cycles of reactions, the photocatalytic CO generation rate remains almost unchanged, demonstrating its excellent cycle stability.

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Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng Zheng Wang Zhou Ying Mo Biao Zheng Miaomiao Han Qin Zhong Wenwen Yang Peng Gao Lezhi Yang Jilei Liu College of materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy