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A planar pentacoordinate oxygen in the experimentally observed [Be5O6]2− dianion

chemical science 2025年 2025 May 16页

作者： Sun, Rui Yang, Yang Wu, Xin Zhai, Hua-Jin Yuan, Caixia Wu, Yan-Bo Key Laboratory of Chemical Biology and Molecular Engineering Ministry of Education Key Laboratory of Materials for Energy Storage and Conversion of Shanxi Province Institute of Molecular Science Shanxi University 92 Wucheng Road Shanxi Taiyuan030006 China Basic Sciences Department Shanxi Agricultural University 1 South Mingxian Road Shanxi Taigu030801 China

Small multiply charged anions (SMCAs) are exceptionally challenging to generate in gas-phase experiments due to the spontaneous detachment of excess electrons. The [Be5O6]2− dianion, first produced in 2006 via electrospray ionization and initially proposed by a concurrent computational study to adopt a linear O-Be-alternating structure, stands as a rare experimentally observed SMCA. In this study, by applying our recently developed electron-compensation strategy, we designed a starlike D5h [O©Be5O5]2− cluster featuring a planar pentacoordinate oxygen (ppO), which intriguingly shares the molecular formula [Be5O6]2−. Remarkably, this ppO isomer is not only 55.8 kcal mol−1 more stable than the previously reported linear isomer but also represents the global energy minimum on the [Be5O6]2− potential energy surface. By adhering to the principles of the electron-compensation strategy, all Be atoms in the ppO isomer are electronically compensated and geometrically shielded by peripheral O atoms, resulting in a well-defined electronic structure. This is evidenced by a positive first vertical detachment energy of 2.44 eV, which effectively prevents the spontaneous loss of excess electrons. Thus, our work serendipitously uncovered and elaborately rationalized an experimentally unprecedented ppO within the previously generated SMCA [Be5O6]2−, marking a significant milestone in the field. © 2025 The Royal Society of Chemistry.

关键词： Isomers

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Co/N-doped carbon nanotube arrays grown on 2D MOFs-derived matrix for boosting the oxygen reduction reaction in alkaline and acidic media

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Chinese chemical Letters 2021年第2期32卷 816-821页

作者： Shuao Wan Jiadong Wu Depeng Wang Huiling Liu Zhicheng Zhang Jianmin Ma Cheng Wang Institute for New Energy Materials and Low-Carbon Technologies School of Materials Science and EngineeringTianjin Key Laboratory of Advanced Functional Porous Materials.Tianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of SciencesTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin 300072China School of Physics and Electronics Hunan UniversityChangsha 410082China Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002China

The development of high-performance and cost-effective electrocatalysts towards oxygen reduction reaction(ORR) is of significant importance,but still challenging for the practical applications in related energy *** process typically suffers from sluggish kinetics,the exploration of ORR electrocatalyst thus requires elaborate ***,an effective strategy is developed for growing Co/N-doped carbon nanotube arrays on 2D MOFs-derived matrix via the pyrolysis of Co/Zn metalorganic-framework(MOF) *** Co/Zn-MOF nanosheets serve as both the self-template for the 2D carbonized framework morphology and C/N source for the in-situ growth of 1D N-doped carbon *** constructed hie rarchical architecture effectively integrates the OD/1D Co nanoparticle/Ndoped carbon nanotube interface and 1D(nanotubes)/2D(nanosheets) junction into frameworks with highly exposed active surface,enhanced mass-transport kinetics and electrical *** a result,the designed composite exhibits superior ORR activity and durability in alkaline media as compared to commercial Pt/***,it shows promising ORR performance with a half-wave potential of 0.78 V versus reversible hydrogen electrode and negligible activity attenuation after 5000 potential cycles in acidic *** designed strategy can be extended to construct other MOFs-derived carbon matrixes with diverse hierarchical structures and provide an efficient avenue for searching highperformance electrocatalysts.

关键词： Carbon nanotube arrays Metal-organic-frameworks derived materials Metal/nitrogen-doped carbon electrocatalysts Oxygen reduction reaction Alkaline and acidic media

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Late-Model N, B, and P-Co-Doped Carbon Dots as Additives for Friction-Reduction and Anti-Wear

SSRN

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SSRN 2023年

作者： Zhu, Wei Tan, Yuhui Tang, Weiwei Li, Yufeng Tang, Yunzhi Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry Department of Materials Metallurgy and Chemistry Jiangxi University of Science and Technology Ganzhou341000 China School of Biological and Chemical Engineering Panzhihua University Panzhihua617000 China

Carbon dots (CDs), a kind of burgeoning carbon-based nanomaterial, were widely used as high-efficiency lubricant additives for promoting the friction-reduction and anti-wear behaviors of green PEG-based lubricating oils. Undoubtedly, advances in CDs-based lubricant additives play a crucial role in enhancing their application prospect and utility value. Therefore, the state-of-the-art N, B, and P-co-doped CDs (N,B,P-CDs) with a diameter of approximately 3.8 nm and composed of amorphous structures were first synthesized by conveniently "one-step" pyrolyzing the corresponding carbon sources and dopants. Noticeably, the synthetic procedures of N,B,P-CDs were uninvolved in any pre-processing and post-processing techniques, showing favorable large-scale preparation potential. Adding suitable concentrations of N,B,P-CDs, the friction-reduction, anti-wear, and load-supporting functions of PEG200 base oil can be maximally increased by 38.1%, 86.2%, and 66.7%, respectively, showing outstanding tribological performances. In addition, the tribological behaviors of N,B,P-CDs are evidently better than that of N,B-CDs and P-CDs under identical test conditions, exhibiting a multiatomic synergistic lubrication effect. According to the wear track surface analysis results and previous reports, the excellent tribological performance of N,B,P-CDs attributes to their favorable film-forming ability (physical adsorption films and tribo-films) and nano-lubrication effect in the different friction stages. © 2023, The Authors. All rights reserved.

关键词： Surface analysis

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Green Monomer of CO_(2) and Alkyne-based Four-component Tandem Polymerization toward Regio-and Stereoregular Poly(aminoacrylate)s

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Chinese Journal of Polymer science 2021年第1期39卷 51-59,I0006页

作者： Bo Song An-Jun Qin Ben Zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesCenter for Aggregation-Induced EmissionSouth China University of TechnologyGuangzhou 510640China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration and ReconstructionInstitute for Advanced StudyDepartment of Chemical and Biological EngineeringThe Hong Kong University of Science&TechnologyHong KongChina

Green monomers, such as carbon dioxide(CO_(2)), are closely related to our daily life and highly desirable to be transferred to functional polymers with diverse structures and versatile properties because they are abundant, cheap, nontoxic, renewable, and sustainable. However, the polymerizations based on these green monomers are to be further developed. In this work, a facile CO_(2) and alkyne-based one-pot, two-step, fourcomponent tandem polymerization was successfully established. The polymerization of CO_(2), diynes, alkyl dihalides, and primary/secondary amines can proceed under mild reaction conditions and regio-and stereoregular poly(aminoacrylate)s with good solubility and thermal stability were obtained in high yields(up to 95%). Notably, distinctly different stereoregularity of resultant poly(aminoacrylate)s was realized via using primary or secondary amines. Using the former would readily generate polymers with 100% Z-isomers, whereas the latter furnished products with over 95% E-isomers. Through different monomer combination, the polymers with tunable structures and properties were ***, the tetraphenylethene units containing poly(aminoacrylate)s, showing the unique aggregation-induced emission characteristics,could function as a fluorescent probe for sensitive explosive detection. Thus, this work not only develops a facile CO_(2) and alkyne-based multicomponent tandem polymerization but also provides a valuable strategy to fine-tune the polymer structures and properties, which could be potentially applied in diverse areas.

关键词： Carbon dioxide Multicomponent tandem polymerization Aggregation-induced emission Green monomer

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Surface engineering Towards Boosted Dielectric Properties for High-Temperature Polymers Under Electrical Extremes

Surface Engineering Towards Boosted Dielectric Properties fo...

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Conference on Electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： Jierui Zhou Marina Dabaghian Anna Marie LaChance Jing Hao Wesley Zhong Luyi Sun Yang Cao Department of Electrical and Computer Engineering University of Connecticut Storrs CT USA Electrical Insulation Research Center Institute of Materials Science University of Connecticut Storrs CT USA Department of Chemical and Biomolecular Engineering University of Connecticut Storrs CT USA Polymer Program Institute of Materials Science University of Connecticut Storrs CT USA

Polymer-thin films are critical dielectric materials for capacitive energy storage in power and electronic systems. The rapid development of wide bandgap semiconductors urgently calls for polymers that can attain high energy density and high charge-discharge efficiency at elevated temperatures. However, high-temperature polymers usually suffer from compromised dielectric breakdown strength and soaring conduction loss due to the intrinsic constraint between their bandgaps and thermal stability. In this work, we propose a facile and high throughput interface engineering technique utilizing nanocoatings formed by montmorillonite (MMT) nanoclays, which can serve as an out-of-the-box solution to bypass this constraint. The highly ordered MMT-based nanocoatings with layered structure can significantly block the excessive charge injection at high electric fields and dissipate the charge carriers along the in-plane direction. The MMT-coated PI films exhibit improved breakdown strength, suppressed conduction loss, and boosted charging-discharging efficiency. This work holds the promise of improving the dielectric properties of polymers through surface engineering, enabling their application at concurrent electrical and thermal extremes.

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In vivo degradation and endothelialization of an iron bioresorbable scaffold

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Bioactive materials 2021年第4期6卷 1028-1039页

作者： Wenjiao Lin Hongjie Zhang Wanqian Zhang Haiping Qi Gui Zhang Jie Qian Xin Li Li Qin Haifeng Li Xiang Wang Hong Qiu Xiaoli Shi Wei Zheng Deyuan Zhang Runlin Gao Jiandong Ding College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China Biotyx Medical(Shenzhen)Co. LtdShenzhen 518109China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China Shenzhen Advanced Medical Services Co. LtdShenzhen518000GuangdongChina Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Key Laboratory of Advanced Technology for Materials of Education Ministry School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Detection of in vivo biodegradation is critical for development of next-generation medical devices such as bioresorbable stents or scaffolds(BRSs).In particular,it is urgent to establish a nondestructive approach to examine in vivo degradation of a new-generation coronary stent for interventional treatment based on mammal experiments;otherwise it is not available to semi-quantitatively monitor biodegradation in any clinical ***,we put forward a semi-quantitative approach to measure degradation of a sirolimus-eluting iron bioresorbable scaffold(IBS)based on optical coherence tomography(OCT)images;this approach was confirmed to be consistent with the present weight-loss measurements,which is,however,a destructive *** IBS was fabricated by a metal-polymer composite technique with a polylactide coating on an iron *** efficacy as a coronary stent of this new bioresorbable scaffold was compared with that of a permanent metal stent with the name of trade mark Xience,which has been widely used in *** endothelial coverage on IBS was found to be greater than on Xience after implantation in a rabbit model;and our well-designed ultrathin stent exhibited less individual *** further examined degradation of the IBSs in both minipig coronary artery and rabbit abdominal aorta *** present result indicated much faster iron degradation of IBS in the rabbit model than in the porcine *** semi-quantitative approach to detect biodegradation of IBS and the finding of the species difference might be stimulating for fundamental investigation of biodegradable implants and clinical translation of the next-generation coronary stents.

关键词： Iron bioresorbable scaffold Species difference Endothelialization In vivo biodegradation Optical coherence tomography

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Fabrication and bioactivity studies of wollastonite/polycaprolactone composites

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International Journal of Nano and Biomaterials 2023年第2期10卷 86-99页

作者： Lakshmi, R. Choudhary, Rajan Senatov, Fedor Kaloshkin, Sergey Kothandam, Shobana Ponnamma, Deepalekshmi Sadasivuni, Kishor Kumar Swamiappan, Sasikumar Department of Chemistry Auxilium College Tamil Nadu Vellore632006 India Faculty of Materials Science and Applied Chemistry Rudolfs Cimdins Riga Biomaterials Innovations and Development Centre of RTU Institute of General Chemical Engineering Riga Technical University Pulka St 3 RigaLV-1007 Latvia Baltic Biomaterials Centre of Excellence Headquarters at Riga Technical University Kipsala Street 6A RigaLV-1048 Latvia National University of Science and Technology "MISiS" Moscow119049 Russia Department of Chemistry School of Advanced Sciences Vellore Institute of Technology Tamil Nadu Vellore632014 India Materials Science and Technology Program Department of Mathematics Statistics and Physics College of Arts and Sciences Qatar University P.O. Box 2713 Doha Qatar Center for Advanced Materials Qatar University P.O. Box 2713 Doha Qatar Department of Chemistry School of Advanced Sciences Vellore Institute of Technology Tamil Nadu Vellore632014 India

Current work investigates the influence of wollastonite on mechanical stability and biomineralisation ability of wollastonite/ polycaprolactone (PCL) composites (WP composites). The solvent casting particulate leaching method was used to prepare these composites. FT-IR spectra indicated the presence of functional groups associated with PCL and wollastonite. Scanning electron microscopy showed aggregated morphology and wollastonite particles were embedded in the PCL matrix. The incorporation of wollastonite leads to a more than three-fold increase in the compressive strength of the composites. Moreover, the composites containing 50% wollastonite exhibited better compressive strength than 80%. This observation suggested that if the concentration of a filler is exceeded beyond its critical concentration then the mechanical stability of the composite will be compromised. The composites revealed good apatite deposition ability. Thus, the biomineralisation ability and compressive strength of PCL can be improved by preparing its composites with bioceramics. © 2023 Inderscience Enterprises Ltd.

关键词： Bioceramics

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Interplay between Autocatalysis and Liquid-Liquid Phase Separation Produces Hierarchical Microcompartments

SSRN

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SSRN 2023年

作者： Hanopolskyi, Anton I. Paikar, Arpita Nutkovich, Boaz Pinkas, Iddo Smith, Barbara S. Orekhov, Nikita D. Skorb, Ekaterina V. Semenov, Sergey N. Department of Molecular Chemistry and Materials Science Weizmann Institute of Science Rehovot Israel Department of Chemical Research Support Weizmann Institute of Science Rehovot Israel School of Biological and Health Systems Engineering Arizona State University TempeAZ United States

Our ability to synthesize life-inspired systems and materials is intimately connected to our understanding of the interplay between reactions, diffusion, phase separation, and self-assembly. The interaction between non-linear reactions (autocatalysis) and liquid-liquid phase separation is particularly interesting because of the emergence of functional properties and structures through instabilities, which are hard to predict theoretically without the help of experimental model systems. In this work, we studied systems where chemical autocatalysis is coupled to complex coacervation and the formation of oil-in-water droplets. The autocatalysis is driven by a nucleophilic chain reaction and is coupled to complex coacervation through the formation of tri- and tetra-cationic species. Interestingly, we observed the formation of hierarchical colloids when we used reactants that can form oil droplets in addition to coacervate droplets. This work illustrates a mechanism for the formation of complex, hierarchical microstructures by kinetically controlled self-assembly regulated by nonlinear chemical reaction networks. © 2023, The Authors. All rights reserved.

关键词： Phase separation

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Correction to: Parameterization of Biot–Willis Effective‑Stress Coefficient for Deformation and Alteration of Porous Rocks

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Transport in Porous Media 2021年第2期140卷 621-622页

作者： Civan, Faruk Department of Chemical Engineering & Materials Science Petroleum Engineering Program University of Southern California Los Angeles USA

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The Endless and Turbulent Frontier of Academic Entrepreneurship

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ACS NANO 2021年第11期15卷 16947-16952页

作者： Kotov, Nicholas A. Liz-Marzan, Luis M. Nie, Zhihong Thuo, Martin M. Zarzar, Lauren D. Department of Materials Science and Engineering Department of Chemical Engineering Biointerfaces Institute University of Michigan Ann Arbor Michigan 48109 United States CIC biomaGUNE Basque Research and Technology Alliance (BRTA) Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine (CIBER-BBN) 20014 Donostia-San Sebastián Spain IKERBASQUE Basque Foundation for Science 48009 Bilbao Spain State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science Fudan University Shanghai 200433 P.R. China Micro-Electronic Research Center Biopolymer and Biocomposites Research Team Center for Bioplastics and Biocomposites Iowa State University Ames Iowa 50011 United States Department of Chemistry and Department of Materials Science and Engineering The Pennsylvania State University University Park Pennsylvania 16802 United States

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