检索结果-南通市图书馆

Interlayer and doping engineering in partially graphitic hollow carbon nanospheres for fast sodium and potassium storage

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第2期34卷 582-587页

作者： Dongfei Sun Sen Lin Dandan Yu Zijuan Wang Fangfang Deng Xiaozhong Zhou Guofu Ma Ziqiang Lei key laboratory of Eco-functional polymer materials of the ministry of education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China

Constructing anodes with fast ions/electrons transfer paths is an effective strategy to achieve high-performance sodium ion batteries(SIBs)/potassium ion batteries(PIBs). Amorphous carbon is a promising candidate anode for SIBs/PIBs owing to its disordered carbon layers, abundant defects/pores, and lowcost resources. However, the larger radius of Na^(+)/K^(+) leading to depressed kinetics and poor cycling performance, impeding their further applications. Herein, we propose an efficient strategy to construct of nitrogen, sulfur co-doped hollow carbon nanospheres(NS-HCS) involving an in situ growth of polydopamine on nano-Ni(OH)2template with subsequent sulfur doping process. During the formation process, the produced Ni nanospheres play as the hard template and catalyst for the formation of hollow carbon nanosphere with partially graphite microcrystalline structure, while the sulfur doping process can enlarge the interlayer space and create more defects on the surface of carbon nanospheres, thus synchronous improve the Na^(+)/K^(+) insertion and adsorption ability in NS-HCS. With the synergistic control of the enlarged interlayer spacing, high content of pyridinic N/pyrrolic N and graphitization, a hybrid storage mechanism facilitates the transport kinetics and endows the NS-HCS electrode with high capacities and good cycling stability in SIBs and PIB. Benefit from the multiple effects, NS-HCS exhibits the improved capacity of 274.8 m Ah/g at 0.1 A/g and excellent cycling stability of 149.5 m Ah/g after 5000 cycles at2.5A/g in SIBs, as well as good potassium ion storage behavior with a high capacity retention of 76.5%after 700 cycles at 1.0 A/g, demonstrating the potential applications of NS-HCS for high-performance SIBs and PIBs.

关键词： Heteroatom doping Hollow carbon nanosphere Long cycle life Hybrid storage mechanism Sodium ion batteries Potassium ion batteries

Chirality and chiral functional composites of bicontinuous cubic nanostructured cubosomes

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2022年第3期33卷 1488-1492页

作者： Deyin Wang Hongkai Liu Wei Wang Center for Synthetic Soft materials Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

Molecular self-assembly is the most important strategy for the development of chiral aggregates and chiral functional materials. In this study, we rationally designed and synthesized chiral fluorescent heteroclusters that were self-assembled into microscale cubosomes with a three-dimensional(3D) bicontinuous cubic phase nanostructure. The cubosomes exhibited chirality, indicating that chirality is transferred from the molecules to the 3D nanostructure. Therefore, we confirmed the formation of a chiral bicontinuous cubic phase nanostructure for the first time. We also showed that this chirality originates from the continuous change in the saddle-splay distortion of the molecules within the curved bilayer. At the same time, transparent films of chiral composites were prepared by mixing the chiral cubosomes with an epoxy resin and then curing the mixture. Therefore, we demonstrated an effective method for preparing chiral composites.

关键词： Chirality Self-assembly Nanostructure Composite

Scattering Function and Spinodal Transition of Linear and Nonlinear Block Copolymers Based on a Unified Molecular Model

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of polymer Science 2021年第6期39卷 779-788,I0009页

作者： Weichao Shi Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

This work uses a block copolymer architecture[(A′B)nA2]m to unify the scattering function and spinodal transition of typical AB-type block copolymers.The key roles of block number,junction points and asymmetry ratios of block length are(1)to determine the form factor of each block copolymer at the molecular scale;(2)to affect the entropy loss across the spinodal transition and may result in deflection of spinodal curves.The common features are validated in typical linear and nonlinear block copolymers,including AB diblock,asymmetric A′BA triblock,miktoarm stars of ABn,AnBn,(AB)n,(A′B)nA,A′BAm,and multi-graft combs of(BnA2)m and[(A′B)nA2]m.The explicit scattering functions and form factors of various block copolymers can be directly applied in radiation experiments(i.***.neutron or X-ray scattering)to unravel the effect of molecular architecture in solution and microphase separation in disordered melt.The molecular model used in this study is also helpful to guide the chemical synthesis to explore more potentially interesting block copolymers.

关键词： Scattering function Form factor Spinodal transition Molecular structure Block copolymer

PREPARATION OF SINGLE-HOLE HOLLOW polymer NANOSPHERES BY RASPBERRY-LIKE TEMPLATE METHOD

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of polymer Science 2013年第2期31卷 294-301页

作者： Yong Zhang Jia-jia Chen Geng-hui Zhang Bai-zhu Chen 阎虎生 key laboratory of functional polymer materials (ministry of education) Institute of Polymer Chemistry Nankai University

Single-hole hollow polymer nanospheres were fabricated by raspberry-like template method using ＂graft-from＂ strategy through atom transfer radical polymerization （ATRP）. Nanometer-sized silica spheres were covalently attached onto the surfaces of micrometer-sized silica spheres. Crosslinked polymer shells on the nano-sized spheres outside the attached area were formed by ＂graft-from＂ strategy through ATRP. After removal of the silica cores, single-hole hollow crosslinked polymer nanospheres were obtained. In this strategy, most of ATRP monomers may be used and thus many functional groups can be easily incorporated into the single-hole hollow crosslinked polymer nanospheres.

关键词： Single-hole Hollow polymeric nanoparticles ATRP.

Heteroatom-doped porous carbon-supported single-atom catalysts for electrocatalytic energy conversion

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第12期30卷 54-73,I0002页

作者： Yue Shao Zhengtai Zha Hong Wang key laboratory of functional polymer materials Ministry of EducationInstitute of Polymer ChemistryCollege of ChemisttyNankai University.Tianjin 300071China

Electrocatalysts play a crucial role in the development of renewable energy conversion and storage nanotechnologies.The unique advantages of heteroatom-doped porous carbon-supported single-atom electrocatalysts(SAC-HDPCs)are clear.These SAC-HDPCs exhibit outstanding activity,selectivity and stability due to their distinct electronic structure,satisfactory conductivity,controllable porosity and heteroatomdoping effect.Rapid and significant developments involving the synthesis,characterization,and structure-property-function relationship of SAC-HDPCs have been made in recent years.In this review,we describe recent research efforts involving advanced(in situ)characterization techniques,innovative synthetic strategies,and electrochemical energy conversion examples of SAC-HDPCs.The electrocatalytic performance of SAC-HDPCs is further considered at an atomic level,and the mechanisms underlying this performance are also discussed in detail.We expect that these analyses and deductions will be useful for the design of new materials and may help to establish a foundation for the design of future SAC-HDPCs.

关键词： Carbon material Heteroatom doping Single-atom electrocatalyst Electrocatalytic energy conversion

Surfactant Mediated Microphase Separation in Miscible Block Copolymer of Poly(4-vinyl pyridine-b-hydroxybutylacrylate)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of polymer Science 2023年第6期41卷 897-904,I0007页

作者： Xiang-Yun Xu Yu-Tong Gao Ying-Ying Wang You-Shuang Zhou Bi-Jin Xiong Jin-Tao Zhu key laboratory of materials Chemistry for Energy Conversion and Storage(HUST)of ministry of education School of Chemistry and Chemical Engineering.Huazhong University of Science and Technology(HUST)Wuhan 430074China key laboratory of Optoelectronic Chemical materials and Devices(ministry of education) Jianghan UniversityWuhan 430056China key laboratory of Green Preparation and Application of functional materials(ministry of education) Hubei Key Laboratory of Polymer MaterialsFaculty of Materials Science and EngineeringHubei UniversityWuhan 430062China

Miscible disordered block copolymers(BCPs)are rarely studied due to the limits in self-assembly into ordered microstructures.Herein,we proposed a facile method for the transformation of disordered miscible BCPs to comb-like BCPs with well-ordered microphase separation structures via blending with amphiphilic surfactants.In this work,poly(4-vinyl pyridine-b-hydroxybutylacrylate)(P4VP-b-P4HBA)was applied as a model of miscible disordered BCPs and the microphase separation was induced via blending with surfactants of dodecylbenzene sulfonic acid(DBSA)and 3-pentadecylphenol(PDP).The ordered microstructures including spherical and cylindrical morphologies were confirmed by transmission electron microscopy(TEM)and small angle X-ray scattering(SAXS)investigation.These ordered microstructures thermal sensitive,in which ordered and disordered transformation(ODT)was observed in the blend of P4VP-b-P4HBA and PDP whereas it disappeared in the blend of P4VP-b-P4HBA and DBSA.The results show that the thermal stability of the ordered microstructures are strongly depends on the interactions between the miscible BCPs and surfactants,which investigated by in situ SAXS and Fourier transform infrared spectrometer(FTIR).The combination of miscible BCPs and surfactant creates a feasible strategy to fabricate ordered nanostructures,which could be employed to develop complicated nanomaterials.

关键词： ordered disordered vinyl

One-pot enantioselective construction of 3,4-dihydro-2H-1,4-oxazines over Ru/Au relay catalysis and its mechanistic serendipity

在线全文

学校读者我要写书评

暂无评论

Organic Chemistry Frontiers 2022年第1期9卷 102-108页

作者： Dongfeng Yang Chengyi Wang Yu Wang Guohua Liu Tanyu Cheng Rui Liu Joint laboratory of International Cooperation of Resource Chemistry of ministry of education Key Laboratory of Resource Chemistry of Ministry of Educationand Shanghai Key Laboratory of Rare Earth Functional MaterialsShanghai Normal UniversityShanghaiChina

The preparation of enantiomerically pure 1,4-oxazines remains a continuous challenge in synthetic chemistry because of their potential application in the total synthesis of morpholines.Herein,a one-pot asymmetric transfer hydrogenation/cyclization enantio-relay process catalyzed by Ru and Au bimetallic catalysts was developed.This enantio-relay process firstly allows the asymmetric transfer hydrogenation of alkynones to form chiral alkynols in the presence of(S,S)-mesityleneRuClTsDPEN(TsDPEN=N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine)and then the chiral alkynols could be converted into 3,4-dihydro-2H-1,4-oxazines in moderate to good yields with excellent enantioselectivity retention accompanied by AuCl(PPh_(3))/AgNTf_(2) and HCOOH.A series of sulfonamide-tethered alkynones were well tolerated in this process.Mechanistic studies indicated that the alkynols formed in the first step were initially transformed into a methylenemorpholine intermediate when AuCl(PPh_(3))/AgNTf_(2) and HCOOH were added,which can be further isomerized into chiral 3,4-dihydro-2H-1,4-oxazines with the addition of a second HCOOH.This protocol offers not only a practical method to access 3,4-dihydro-2H-1,4-oxazines from alkynones in an enantioselective version,but also enriches the arsenal of gold chemistry from a mechanistic point of view.

关键词： process chiral hydrogenation

Oxygen vacancy-rich MoO_(3)nanorods as photocatalysts for photo-assisted Li-O_(2) batteries

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2023年第4期12卷 747-759页

作者： Guiru Sun Daming Yang Zexu Zhang Yan Wang Wei Lu Ming Feng key laboratory of functional materials Physics and Chemistry of the ministry of education Jilin Normal UniversityChangchun 130103China

Photo-assisted lithium-oxygen(Li-O_(2))batteries have been developed as a new system to reduce a large overpotential in the Li-O_(2)batteries.However,constructing an optimized photocatalyst is still a challenge to achieve broad light absorption and a low recombined rate of photoexcited electrons and holes.Herein,oxygen vacancy-rich molybdenum trioxide(MoO_(3-x))nanorods are employed as photocatalysts to accelerate kinetics of cathode reactions in the photo-assisted Li-O_(2)batteries.Oxygen vacancies on the MoO_(3-x)nanorods can not only increase light-harvesting capability but also improve electrochemical activity for the cathode reactions.Under illumination,the photoexcited electrons and holes are effectively separated on the MoO_(3-x)nanorods.During discharging,activated O2 is reduced to Li_(2)O_(2)by the photoexcited electrons from the MoO_(3-x)nanorods.The photoexcited holes can promote the decomposition of Li_(2)O_(2)during subsequent charging.Accordingly,the photo-assisted Li-O_(2)batteries with the MoO_(3-x)nanorods deliver an ultralow overpotential of 0.22 V,considerable rate capability,and good reversibility.We think that this work could give a reference for the exploitation and application of the photocatalysts in the photo-assisted Li-O_(2)batteries.

关键词： molybdenum trioxide(MoO_(3))nanorods oxygen vacancy photocatalyst photo-assistance lithium-oxygen(Li-O_(2))batteries

Self-assembled nanochaperones enable the disaggregation of amyloid insulin fibrils

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2022年第2期65卷 353-362页

作者： Hui Wang Ang Li Menglin Yang Yu Zhao Linqi Shi Rujiang Ma Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China State key laboratory of Medicinal Chemical Biology Nankai UniversityTianjin 300071China

The deposition of highly ordered amyloid fibrils is recognized as a hallmark of amyloidosis diseases such as Alzheimer’s disease and Parkinson’s disease.Disaggregating the amyloid fibrils is considered as one of the effective strategies for the control and treatment of amyloidosis diseases.In this article,by simulating the function of natural molecular chaperones,co-assembled block copolymer micelles with coordination groups of nitrilotriacetic acid(NTA)and hydrophobic microdomains of poly(Nisopropylacrylamide)(PNIPAM)on the surface were used as nanochaperones(n Chaps)to disaggregate amyloid insulin fibrils.Zinc ions chelated by NTA can bind the histidine imidazole residues while the PNIPAM microdomains can interact with the exposed hydrophobic sites on the amyloid insulin fibrils,which synergistically perturb the stability of amyloid insulin fibrils,loosen their structure,and finally promote their disaggregation.A combination of characterizations with fluorescence spectroscopy,transmission electron microscopy(TEM),dynamic hight scattering(DLS),and quartz crystal microbalance(QCM)demonstrated that mature amyloid insulin fibrils were completely disaggregated after incubating with n Chaps for 90 h.This study may provide a promising strategy for the development of n Chaps for the treatment of amyloidosis diseases.

关键词： amyloid fibrils insulin nanochaperones disaggregation