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Ultrastrong room-temperature phosphorescence in cucurbit[8]uril-mediated crystalline supramolecules for ratiometric detection of phenethylamine

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Science China Chemistry 2025年

作者： Qingyu Niu Yingxiang Ye Lingna Su Xu He Zhiqiang Li Yu Liu School of Chemical Engineering and Technology Hebei University of Technology Fujian Provincial key laboratory of Polymer materials College of Chemistry and Materials Science Fujian Normal University key laboratory of Advanced Energy materials Chemistry (Ministry of Education) Nankai University College of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University

It is a great challenge to modulate purely organic fluorescence-phosphorescence dual emission in aqueous solution because the excited singlet and triplet states are in competition with each other. Herein, we report a crystalline 1:2 host-guest formed by selfassembly of 4-(4-bromophenyl)-pyridinium derivatives and cucurbit[8]uril, in which a rigid environment rich in weak interactions is directly demonstrated. Due to the inhibition of non-radiative transition and stabilization of triplet exciton in the crystalline environment, the crystalline inclusion complex exhibits ultralong room-temperature phosphorescence lifetime of 3.21 ms with an room-temperature phosphorescence(RTP) quantum yield up to 16.29%. Interestingly, the crystalline 1:2 hostguest complex demonstrates the ability of rapid identification and sensitive fluorescence-phosphorescence ratiometric detection behavior toward phenethylamine, a drug analogue, with a limit of detection as low as 27.5 nM. We believe that this study will undoubtedly broaden the utilizing scopes of RTP and offer a novel avenue for psychoactive substances monitoring.

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Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li Shen Du Ming Gao Yanbin Yin Jiongming Zhang state key laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

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Ca2+ cation-mediated microenvironment for electrochemical hydrodimerization of furfural

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Science China Chemistry 2025年

作者： Wei Du Shuangshuang Cha Can Lei Mengxin Qu Zhongqiang Deng Ming Gong Xinhe Bao Department of Chemistry and Shanghai key laboratory of Molecular Catalysis and Innovative materials Fudan University state key laboratory of Catalysis National Laboratory for Clean Energy Collaborative Innovation Center of Chemistry for Energy Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences

Furfural is one of the most important biomass-based platform molecules as sustainable precursors for chemicals and fuels. The electrochemical hydrodimerization of furfural can generate hydrofuroin, which is a promising precursor for gasoline or jet ***, steering the selectivity toward hydrodimerization under near-neutral conditions that suppress polymerization and disproportionation of furfural remains challenging. Herein, we discovered that tuning the electrolyte cations could be an effective and alternative strategy for modulating furfural reduction to the traditional electrocatalyst design. Under the optimal Ca2+cations,hydrofuroin yield could be much improved from other cations with hydrofuroin selectivity of 95.5%. The systematic characterization of the ion-centered double layer reflected the suitable sizes and charges of hydrated Ca2+for suppressing the hydrogen evolution reaction from activation of surrounding water molecules as well as encouraging furfural accumulation via non-covalent interaction for directing the electron transfer to furfurals. Ions with smaller or larger sizes can either activate local water molecules or form a crowded ionic interface that casts an adverse effect on furfural enrichment. This work not only presents an effective strategy for facilitating biomass valorization via hydrodimerization but also emphasizes the essential role of the ion-centered microenvironment for steering the electrocatalytic pathways.

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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han Jia Tuo Liu Yuzhen Yang Jun Yang key laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences state key laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Controlled cationic ring-opening polymerization of L-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期 394-402页

作者： Zhiqiang Ding Mingqian Wang Zijing Zhou Bin Wang Yuesheng Li Tianjin key laboratory of Composite & Functional materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

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Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen Yu Han Jun Wang Shibo Xi Yu Zhou state key laboratory of materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

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Journal of Energy Chemistry 2025年第1期100卷 612-620页

作者： Weiwei Yu Xinbao Zhang Hongyu Chen Yanan Wang Shaoguo Li Fucun Chen Zhenni Liu Xiujie Li Xiangxue Zhu state key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=***,a novel Al2O3/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol Cross-linking Carbon supported Al 2 O 3 MPV route

Polybenzimidazolium-reinforced polyimide separators to inhibit dendrites for high-security lithium-ion batteries

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Science China Chemistry 2025年

作者： Guohua Sun Jiaqi Cui Qingsong Zhang Yisong Zhou Xinluo Li Yingying Zhang Zhanao Zhang Xin Zhang Jiantao Fan Pengpeng Li Lianlong Hou Nanjun Chen Hebei key laboratory of Flexible Functional materials School of Materials Science and Engineering Hebei University of Science and Technology state key laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology state key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University

Lithium dendrite formation poses a significant safety hazard in lithium-ion batteries（LIBs）, severely impeding their widespread adoption and further technological advancements. Here, we present a novel quaternized polybenzimidazolium（q-PBI） to armor polyimide（PI） nanofiber separator（q-PBI@PI）, in which the q-PBI containing lithiophilicity and anionphilicity sites serves as the multifunctional nano-layers to suppress the Li dendrite and reinforce the mechanical properties of PI nanofiber ***, the q-PBI@PI separator displays an unprecedented mechanical strength of 82.8 MPa, significantly outperforming previously reported PI nanofiber membranes（typically below 50.0 MPa）. Besides, we demonstrate that the q-PBI@PI separator simultaneously possesses low nucleation overpotential（59 mV） and exceptional average coulombic efficiency due to the suppression of Li dendrite. Importantly, q-PBI@PI-based Li||Li battery enables a stable Li plating-stripping at 1.0 m A cm-2for600 h. Attributing to these exceptional merits, the armored PI separator-based LIBs display remarkable specific capability and capacity retention. The density function theory calculations reveal that q-PBI is conducive to the desolvation of Li+and can immobilize Li+and PF6-ions near affinity sites of PI nanofibers for inhibiting the formation of Li dendrites. Our work paves a new avenue for the design of next-generation high-performing separators in LIBs.

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Flexible molecules dedicate to release strain of inverted inorganic perovskite solar cell

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Journal of Energy Chemistry 2025年第1期100卷 87-93页

作者： Hongrui Sun Sanlong Wang Pengyang Wang Yali Liu Shanshan Qi Biao Shi Ying Zhao Xiaodan Zhang Institute of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage Center State Key Laboratory of Photovoltaic Materials and CellsNankai University key laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Haihe laboratory of Sustainable Chemical Transformations Engineering Research Center of Thin Film Photoelectronic Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells （IPSCs）,which reduces the defect formation ***,a flexible molecule 5-maleimidovaleric acid （5-MVA） was introduced as a strain buffer to release the residual strain of *** anhydride and carboxyl groups in 5-MVA interact strongly with the uncoordinated Pb2+through Lewis acid-base reaction,thus tightly“pull”the perovskite *** in-between soft carbon chain increased the structural flexibility of CsPbI2.85Br0.15perovskite materials,which effectively relieved the intrinsic internal strain of CsPbI2.85Br0.15,resisted the corrosion of external strain,and also reduced the formation of defects such as VIand *** addition,the introduction of 5-MVA improved crystal quality,passivated residual defects,and narrowed energy level ***,power conversion efficiency （PCE） of NiOxbased inverted IPSCs increased from 19.25% to 20.82% with the open-circuit voltage enhanced from 1.164 V to 1.230 *** release of strain also improved the stability of CsPbI2.85Br0.15perovskite films and devices.

关键词： Perovskite solar cells