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Self-assembly Induced by Complexation of Diblock Copolyelectrolytes and Oppositely Charged Homopolymers

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Chinese Journal of Polymer science 2024年第9期42卷 1321-1332,I0006页

作者： Ling Zhao Zhi-Yuan Yin Jia-Di Jiang Er-Qiang Chen Shuang Yang Beijing National Laboratory for molecular sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Mater Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Beijing National Laboratory for molecular sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers,in which the A blocks are negatively charged,and the B blocks are *** electrostatic complexation between oppositely charged polymers drives the formation of many ordered *** microstructures and phase diagrams are calculated using self-consistent field theory(SCFT)based on an ion-pair model with an equilibrium constant K to characterize the strength of binding between positively and negatively charged *** effects of the charge ratio,representing the ratio of charges from the homopolymer over all charges from polymers in the system,on the ordered structure are systematically studied,both for hydrophobic and hydrophilic A *** charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer *** also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed,and the results are in good agreement with *** studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems.

关键词： Self-assembly Polyelectrolyte complexation Self-consistent field theory Ion-pair

A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer science 2024年第8期42卷 1210-1216页

作者： Li-Bang Xiao Zi-Han Wu Jun-Jie Xin Yuan-Peng Cheng Bo Gui Jun-Liang Sun Cheng Wang college of chemistry and molecular sciences Wuhan UniversityWuhan 430072China college of chemistry and molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption

Catalytic recycling of polyesters via a binuclear catalyst

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science China chemistry 2024年第2期67卷 426-427页

作者： Bo Sun Ding Ma Beijing National Laboratory for molecular science New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

Plastics play a crucial role in modern society life. While the increasing use of plastics and rapid accumulation of plastic waste in nature environment have caused severe environmental crisis and the waste of carbon resources. Catalytic upcycling is a promising approach to transform plastic waste into high value-added chemicals to achieve a sustainable circular economy.

关键词： Catalytic polyester catalyst

Capturing metal clusters at the strong-interaction region to reverse Ostwald ripening

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science China Materials 2024年第4期67卷 1363-1364页

作者： Shuheng Tian Ding Ma Beijing National Laboratory for molecular sciences New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

High-temperature interactions induce sintering of metal nanoparticles(NPs) on heterogeneous catalyst surfaces, leading to reduced surface area and active site loss through Ostwald ripening [1]. This irreversible deactivation necessitates costly catalyst replacement, notably impacting metals like copper in hydrogenation and reforming reactions [2].

关键词： catalyst reforming irreversible

Multidimensional coupled structure-activity relationship models for replacement of SF_(6)

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High Voltage 2024年第2期9卷 484-494页

作者： Mi Zhang Hua Hou Baoshan Wang college of chemistry and molecular sciences Wuhan UniversityWuhanChina

Computational screening of single gases to replace SF_(6)for electrical insulation has been challenged by the difficulty in combining various mutually exclusive properties especially for dielectric performance with liquefaction and environmental *** reveal the inherent correlations between dielectric strength(Er),boiling point(Tb),and global warming potential(GWP)of dielectric materials,a coupled structure-activity relationship(CSAR)model has been proposed for the first *** means of the generic descriptors,as deduced from the electrostatic potentials,and the specific descriptors,as introduced from the respective microscopic mechanisms,the complex interdependence between Er,Tb,and GWP of the insulation gases is quantitatively characterised by the 3-D coupling *** coupling mechanism for the right balance of properties is uncovered in terms of the first-principle *** CSAR model outperforms the previous SAR models in predicting Er,Tb,and GWP simultaneously in a self-consistent *** importantly,the concept of CSAR could be extended readily to any multidimensional macroscopic *** replacement compounds have been identified tentatively to be the promising candidates to replace SF_(6)using the CSAR model.

关键词： properties. dielectric insulation

Polyelectrolyte Complexes and Coacervates Formed by De novo-Designed Peptides and Oligonucleotide

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Chinese Journal of Polymer science 2024年第9期42卷 1333-1340,I0007页

作者： Tian-Hao Ren De-Hai Liang Beijing National Laboratory for molecular sciences Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic *** the regulation mechanism is still a *** this work,we designed a series of peptides(XXLY)_(6)SSSGSS and studied their complexation and coacervation behavior with single-stranded ***“X”and“Y”are varied to combine known amounts of charged and non-charged amino acids,together with the introduction of secondary structures and pH *** show that the electrostatic interaction,which is described as charge density,controls both the strength of complexation and the degree of chain relaxation,and thus determines the growth and size of the *** hydrophobic interaction is prominent when the charges are ***,the secondary structures of peptides exhibit profound effect on the morphology of the phases,such as solid phase to liquid phase *** study gains insight into the phase separation under physiological *** is also helpful to create coacervates with desirable structures and functions.

关键词： Polyelectrolyte complex Coacervate Peptides Secondary structure Electrostatic interaction

Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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science China chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song Rui Zeng Hui Xiao Hailiang Ni Zong-Xiang Xu Haifeng Xiang college of chemistry and Materials science Sichuan Normal University Department of chemistry Southern University of Science and Technology college of chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear Pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based Pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no Pt-Pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 10～3cd m-2, 41.9 cd A-1, 18.8 lm W-1, 12.6% and 2.98 × 10-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： Pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

Bright InP quantum dots by Ga-doping for red emitters

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Nano Research 2024年第7期17卷 6721-6733页

作者： Kai-Zheng Song Xiao-Hang He Zhe-Yong Chen Ge Tang Jin-Zhao Huang Feng-Lei Jiang college of chemistry and molecular sciences Wuhan UniversityWuhan 430072China

Environment-friendly indium phosphide(InP)-based quantum dots(QDs)with efficient red-emitting properties are sufficiently needed to satisfy the requirement of burgeoning display and lighting ***,the syntheses of InP QDs using tris(trimethylsilyl)phosphine as the precursor are highly toxic and ***,we successfully introduced gallium(Ga)ions into tris(dimethylamino)phosphine-based red InP cores through thermally-promoted cation exchange,and the obtained Ga-doped InP cores exhibited significantly increased photoluminescence quantum yields(PLQY)of up to 26%.The existence of Ga was directly confirmed by energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy,and the functions of Ga were systematically *** subsequent coating of Ga-doped InP cores with ZnSeS and ZnS shells,the resulting Ga-InP/ZnSeS/ZnS QDs achieved a high PLQY of 62%with an emission maximum at 640 *** contrast,without Ga-doping,the PLQY only attained 36%using the same synthetic *** indicated an approximate 1.7-fold increase in *** enhancement of photoluminescence was related to the Ga^(3+),as it not only passivated surface defects of InP cores but also reduced core–shell interface *** Ga-InP/ZnSeS/ZnS QDs exhibited good stability towards heat treatment and ultraviolet(UV)***,the red light-emitting diode(LED)based on Ga-InP/ZnSeS/ZnS QDs performed well in a wide injected current range of 2 to 200 mA,with a maximum power efficiency of 0.68 lm/*** work showcases Ga-doping through cation exchange as a promising strategy for enhancing the efficiency of InP-based red emitters.

关键词： indium phosphide gallium doping optical properties light emitting diode

Towards wafer-scale growth of two-dimensional cerium dioxide single crystal with high dielectric performance

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Nano Research 2024年第9期17卷 8592-8599页

作者： Zhuofeng Shi Muhammad Imran Xiaohui Chen Xin Liu Yaqi Zhu Zhaoning Hu Saiyu Bu Jialin Zhang Chunhu Li Xiaodong Zhang Li Lin college of chemistry and Chemical Engineering Qingdao UniversityQingdao 266000China School of Materials science and Engineering Peking UniversityBeijing 100871China Center for Nanochemistry Beijing Science and Engineering Center for NanocarbonsBeijing National Laboratory for Molecular ScienceCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of Marine chemistry Theory and Technology Ministry of EducationCollege of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

Owing to the atomically thin nature,two-dimensional(2D)oxide materials have been widely reported to exhibit exciting transport and dielectric properties,such as fine gate controllability and ultrahigh carrier mobility,that outperform their bulk ***,unlike the successful synthesis of bulk oxide single crystals,reliable methods for synthesizing large-area single crystal of 2D oxide,that would suppress the negative influence from defective grain boundaries,remain unavailable,especially for nonlayered ***,we report that the lattice symmetry between the substrate and cerium dioxide(CeO_(2))would allow for the aligned nucleation and epitaxial growth of CeO_(2)on sapphire substrates,enabling the wafer-sized growth of CeO_(2)single *** careful tuning of the growth temperature and oxygen flow rate contributed to the harvesting of CeO_(2)wafer with reduced thickness and enhanced growth *** removal of grain boundaries improved the dielectric performance in terms of high dielectric strength(E_(bd)≈8.8 MV·cm^(-1)),suppressed leakage current,along with high dielectric constants(ε_(r)≈24).Our work demonstrates that with fine dielectric performance and ease of synthesizing wafer-sized single crystals,CeO_(2)can function as potential candidate as gate insulator for 2D-materials based nanoelectronics,and we believe the reported protocol of aligned nucleation can be extended to other 2D oxides.

关键词： dielectric materials two-dimensional materials chemical vapor deposition cerium dioxide