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Theoretical investigation of electron-impact ionization of W8+ion

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Chinese Physics B 2024年第3期33卷 341-349页

作者：张世平张芳军张登红丁晓彬蒋军颉录有马玉龙李麦娟 Marek Sikorski 董晨钟 key laboratory of Atomic and Molecular Physics & Functional materials of gansu province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070China

The electron-impact single ionization cross section for W8+ion has been calculated using flexible atomic code,employing the level-to-level distorted-wave *** calculations takes into account contributions form both direct ionization(DI)and excitation autoionization(EA).However,the theoretical predictions,based solely on the ground state,tends to underestimate the experimental *** discrepancy can be mitigated by incorporation contributions from excited *** extended the theoretical analysis,including the contributions from the long-lived metastable states with lifetimes exceeding 1.5×10-5 *** employed two statistical models to predict the fraction of ground state ions in the parent ion *** a 79%fraction of parent ions in ground configuration,the experiment measurements align with the *** we derived the theoretical cross-section for the ground state as correlated plasma rate coefficients,and compared it with existing *** the uncertainty in our calculations,our results are still acceptable.

关键词： tungsten ions electron-impact ionization cross section

A novel fused bi-macrocyclic host for sensitive detection of Cr_(2)O_(7)^(2-)based on enrichment effect

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Chinese Chemical Letters 2024年第7期35卷 291-295页

作者： Ting-Ting Huang Jin-Fa Chen Juan Liu Tai-Bao Wei Hong Yao Bingbing Shi Qi Lin 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 key laboratory of Environment-Friendly Composite materials of the State Ethnic Affairs Commission Gansu Provincial Biomass Function Composites Engineering Research CenterCollege of Chemical EngineeringNorthwest Minzu University(Northwest University for Nationalities)Lanzhou 730000China

Improving the highly selective and sensitive binding of chemosensor to target guest is always very *** order to solve this issue,herein,the enrichment effect was introduced into the design of chemosensor molecule.A novel bi-fused-macrocyclic host molecule BPN1 was synthesized by bridging a pillar[5]arene and a naphthalene diimide(NDI)group through hydrogen-bond-rich *** the BPN1,the naphthalimide side ring is outside the cavity of the pillar[5]*** addition,Cr(VI)greatly threat human health and the environment due to its severe toxicity,and it is very important to develop effective chemosensor for sensitive and selective detection of Cr_(2)O_(7)^(2-)or its ion *** this paper,the novel bi-fused-macrocyclic host molecule BPN1 can recognize Cr_(2)O_(7)^(2-)with high selectivity and *** mechanism of BPN1 recognition of Cr_(2)O_(7)^(2-)was studied through experiments and density functional theory(DFT),the results show that BPN1 could supply enrichment effect to bind Cr_(2)O_(7)^(2-)through multiple weak interactions such as hydrogen bonds and anion-π,and achieve highly sensitive and selective detection of Cr_(2)O_(7)^(2-).It is a significant and feasible strategy for improve high selectivity and sensitivity of host to specific objects by using the enrichment effect of fused bi-macrocyclic.

关键词： Pillararene Bi-macrocyclic Detection of Cr_(2)O_(7)^(2−) DFT The enrichment effect

3D printing encouraging desired in-situ polypyrrole seed-polymerization for ultra-high energy density supercapacitors

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Journal of Energy Chemistry 2024年第8期95卷 117-125,I0004页

作者： Tiantian Zhou Shangwen Ling Shuxian Sun Ruoxin Yuan Ziqin Wu Mengyuan Fu Hanna He Xiaolong Li Chuhong Zhang State key laboratory of polymer materials Engineering Polymer Research InstituteSichuan UniversityChengdu 610065SichuanChina

The tireless pursuit of supercapacitors with high energy density entails the parallel advancement of wellsuited electrode materials and elaborately engineered ***(PPy)emerges as an exceedingly conductive polymer and a prospective pseudocapacitive materials for supercapacitors,yet the inferior cyclic stability and unpredictable polymerization patterns severely impede its real-world ***,for the first time,an innovative seed-induced in-situ polymerization assisted 3D printing strategy is proposed to fabricate PPy-reduced graphene oxide/poly(vinylidene difluoride-cohexafluoropropylene)(PVDF-HFP)(PPy-rGO/PH)electrodes with controllable polymerization behavior and exceptional areal mass *** preferred active sites uniformly pre-planted on the 3D-printed graphene substrates serve as reliable seeds to induce efficient polypyrrole deposition,achieving an impressive mass loading of 185.6 mg cm^(-2)(particularly 79.2 mg cm^(-2)for polypyrrole)and a superior areal capacitance of 25.2 F cm^(-2)at 2 mA cm^(-2)for a 12-layer *** agreement with theses appealing features,an unprecedented areal energy density of 1.47 mW h cm^(-2)for a symmetrical device is registered,a rarely achieved value for other PPy/rGO-based *** work highlights a promising route to preparing high energy density energy storage modules for real-world applications.

关键词： 3D printing Seed-induced polymerization Supercapacitor Polypyrrole High energy density

Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

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Chinese Journal of polymer Science 2024年第2期42卷 256-266,I0010页

作者： Can-Can Zhang Jun-Long Yang Ya-Jiang Huang Guang-Xian Li College of polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction

Rapid and controllable in-situ self-assembly of main-group metal nanofilms for highly efficient CO_(2)electroreduction to liquid fuel in flow cells

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Nano Research 2024年第6期17卷 5718-5725页

作者： Miao Wang Huaizhu Wang Yaoda Wang Junchuan Liang Mengfei Zhu Jiarui Li Zuoxiu Tie Zhong Jin State key laboratory of Coordination Chemistry MOE Key Laboratory of Mesoscopic ChemistryMOE Key Laboratory of High Performance Polymer Materials and TechnologyJiangsu Key Laboratory of Advanced Organic MaterialsTianchang New Materials and Energy Technology Researc

The electrocatalytic reduction of CO_(2)is a promising pathway to generate renewable fuels and ***,its advancement is impeded by the absence of electrocatalysts with both high selectivity and ***,we present a scalable in-situ thermal evaporation technique for synthesizing series of Bi,In,and Sn nanofilms on carbon felt(CF)substrates with a high-aspect-ratio *** resulting main-group metal nanofilms exhibit a homogeneously distributed and highly exposed catalyst surface with ample active sites,thereby promoting mass transport and ad-/desorption of reaction *** from the unique fractal morphology,the Bi nanofilms deposited on CF exhibit optimal catalytic activities for CO_(2)electroreduction among the designed metal nanofilms electrodes,with the highest Faradaic efficiency of 96.9%for formate production at−1.3 V *** hydrogen electrode(RHE)in *** an industrially relevant current density of 221.4 mA·cm−2 in flow cells,the Bi nanofilms retain a high Faradaic efficiency of 81.7%at−1.1 V(***)and a good long-term stability for formate ***,a techno-economic analysis(TEA)model shows the potential commercial viability of electrocatalytic CO_(2)conversion into formate using the Bi nanofilms *** results offer a green and convenient approach for in-situ fabrication of stable and inexpensive thin-film catalysts with a fractal structure applicable to various industrial settings.

关键词： CO_(2)electroreduction non-noble metal nanofilms flow cells efficiency and selectivity techno-economic analysis

Electronic structural engineering of bimetallic Bi-Cu alloying nanosheet for highly-efficient CO_(2) electroreduction and Zn-CO_(2) batteries

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Nano Research 2024年第5期17卷 3684-3692页

作者： Wenbo Wu Jiaye Zhu Yun Tong Shuangfei Xiang Pengzuo Chen School of Chemistry and Chemical Engineering Key Laboratory of Surface and Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou 310018China

Regulating the electronic structure of Bi-based materials by alloying engineering is promising to promote the electrocatalytic activity,but it remains some challenges to be *** this study,a facile electrochemical co-deposition strategy is developed to synthesize the bimetallic Bi_(9)Cu_(1) alloy nanosheet on carbon cloth(Bi_(9)Cu_(1)/CC),which represents a novel self-supporting electrode for the electrocatalytic carbon dioxide(CO_(2))reduction reaction(CO_(2)RR).The Bi_(9)Cu_(1)/CC catalyst has achieved a remarkable catalytic performance with high Faradaic efficiencies(FE)of over 90%for formate at wide potentials from-0.7 to-1.2 V *** hydrogen electrode(RHE).Moreover,the reversible Zn-CO_(2) battery can be driven by Bi_(9)Cu_(1)/CC cathode with a largest power density of 1.4 mW·cm^(-2),and superior operating *** systematic characterizations and electrochemical results confirm that the improved catalytic active sites,the enhanced mass/charge transport and the optimal reaction kinetics of Bi nanosheet are realized for CO_(2)RR by Cu *** situ attenuated total reflection infrared(ATR-IR)result confirms the bimetallic Bi-Cu active sites prefer to follow the^(*)OCHO conversion *** density functional theory(DFT)calculations suggest that the Cu alloying contributes to the increased density of states near the Fermi surface of Bi and the optimized adsorption of^(*)OCHO intermediates on the Bi sites,resulting in the excellent catalytic performance.

关键词： electronic regulation bismuth nanosheet copper alloying CO_(2)electroreduction Zn-CO_(2)batteries

Structural disruption of melanin-like polymers with boosted UV protection

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Science China Chemistry 2024年第5期67卷 1653-1663页

作者： Zhen Yang Xianheng Wang Wanjie Bai Zikun Zou Haoxing Wu Yiwen Li Department of Radiology Huaxi MR Research CenterFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China College of polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Manipulating the energy structure of materials represents an efficient way to regulate their light absorption behaviors. For example, constructing donor-acceptor(D-A) structures to increase the polarizability and reduce the energy bandgap of local molecules has been widely used in the field of organic photovoltaics with ordered structures. Remarkably, even in disordered and chaotic systems such as melanin-like polydopamine(PDA), visible and near-infrared light absorption can be significantly improved using this strategy. However, there has been a noticeable dearth of research on the ultraviolet(UV) light absorption regulation of bioinspired polymers with disordered and chaotic architectures by tailoring the D-A microstructures. In this study, a series of benzoheterocyclic molecules with strong electron-donating features screened by molecular simulation calculations were involved in disrupting the D-A structures within PDA. The destruction of D-A structures promoted the increase of the energy band gap and finally boosted the UV absorption of PDA. The resulting PDA nanoparticles with enhanced UV absorption were further employed to fabricate UV shielding composite films to protect the growth of plants from harmful UV radiation. This research may open up new avenues for structural disruption of bioinspired polymers for enhanced photoprotection applications.

关键词： melanin-like polymers polydopamine D-A structure UV absorption photoprotection

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of polymer Science 2024年第6期42卷 693-710页

作者： Ying Zhou Bai Xue Lan Xie Chang-Mei Wu Qiang Zheng Department of polymer materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of polymer materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State key laboratory of Public Big Data Guizhou University Department of polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler polymer composite Electromagnetic interference shielding

Lightweight foam-like nitrogen-doped carbon nanotube complex achieving highly efficient electromagnetic wave absorption

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Journal of materials Science & Technology 2024年第1期168卷 114-123页

作者： Zongcheng Li Jin Liang Zhiheng Wei Xin Cao Jiahui Shan Chunwei Li Xiaoyi Chen Dong Zhou Ruizhe Xing Chunjia Luo Jie Kong MOE key Lab of materials Physics and Chemistry in Extraordinary Conditions Shaanxi Key Laboratory of Macromolecular Science and TechnologySchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China key laboratory of Flexible Electronics of Zhejiang province Ningbo Institute of Northwestern Polytechnical UniversityNingbo 315103China polymer materials and Engineering Department School of Materials Science and EngineeringChang’an UniversityXi’an 710064China

With the increased electromagnetic wave(EMW)threat to military and human health,the develop-ment of EMW-absorbing materials is ***-organic framework derivatives containing magnetic nanoparticles and a carbon matrix are potential candidates for designing efficient EMW-absorbing ***,a zeolitic imidazolate framework-67(ZIF-67)-embedded three-dimensional melamine foam is pyrolyzed to afford carbon foam-based nitrogen-doped carbon nanotube composites,named 3D foam-like CoO/Co/*** CoO/Co particles are confined in the dielectric carbon nanotube *** carbon nanotubes provide considerable conductive loss,while CoO/Co magnetic particles are con-ducive to providing magnetic loss and adjusting impedance ***,the numerous defect structures introduced by heteroatomic doping(nitrogen)cause dipole polarization and simultaneously adjust impedance ***,the unique porous nanotube structure promotes multiple re-flections and scattering of EMWs,further optimizing impedance ***/Co/N-CNTs composites exhibit a minimum reflection loss of−52.3 dB at a matching thickness of 2.0 mm,while the correspond-ing effective absorption bandwidth is 5.28 GHz at a matching thickness of 2.2 *** study reports a novel approach to fabricating a lightweight high-performance EMW-absorbing material.

关键词： Lightweight porous carbon materials Carbon nanotubes CoO/Co magnetic particles Electromagnetic synergistic effect Impedance matching