Polymer Chemistry
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2021
·Vol. 12
·期 23
·3383-3390
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IF 5.582
Xiaofang Lin,Sisi Chen,Weihong Lu,Ming Liu,Zhengbiao Zhang,Jian Zhu,Xiangqiang Pan
Exploration of new strategies for the preparation of novel polymer materials with diverse topological structures and functions is a subject of enduring interest in the area of polymer science. In this work, diselenide–yne polymerization for the efficient preparation of selenium-containing hyperbranched polymers (Se-HBPs) was established, which could proceed with 100% atom efficiency under blue light irradiation without any external catalyst. Through systematic optimization of the reaction conditions, a series of Se-HBPs with controllable molecular weights and well-defined structures were obtained in high yield (up to 99%) and stereoselectivity (E/Z = 93 : 7). This type of polymer has degrees of branching (DB) almost as high as that of dendrimers because each unit is either terminal or fully branched. During the mild and efficient diselenide–yne polymerization, the molecular weight and terminal group of the hyperbranched polymer could be adjusted by an AB2 + A type copolymerization strategy, providing a powerful tool to tailor the properties of hyperbranched polymers. Fluorescent, aggregation-induced emission (AIE) and amphipathic Se-HBPs could be prepared in a one-pot reaction. Notably, the AIE-terminal Se-HBPs showed a “see-saw” fluorescence performance via the combination of AIE and aggregation-caused quenching (ACQ). The amphipathic Se-HBPs could self-assemble to give nanoparticles, which showed good oxidation-responsive properties. Moreover, colloid gold nanoparticles could be prepared by utilizing these Se-HBPs as both stabilizers and reductants, which exhibited sensitive oxidative response to 0.01 wt% H2O2. We believe that the simplicity and versatility of diselenide–alkyne polymerization will open up enormous opportunities for preparing multifunctional smart polymeric materials.
研究领域:
高分子科学
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材料化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Tianjian Xu,Taotao Zeng,Ningyi Zhang,Zhanglong He,Yuling Liu,Hao He,Zhao liang,Zeyan Zhou,Shuaiming He
The strategic design of atomic-efficient catalysts through targeted bonding engineering remains pivotal for advancing oxygen reduction reaction (ORR) in metal-air batteries. This study pioneers a comparative investigation between surface-engineering Ce O bond construction (Ce surface decorated MnO 2 , Ce-SD-MnO 2 ) and conventional bulk doping strategy (Ce bulk doping MnO 2 , Ce-BD-MnO 2 ), revealing fundamental structure-activity relationships. Advanced High-Angle Annular Dark-Field Scanning Transmission Electron Microscopy (HAADF-STEM) and X-ray Absorption Fine Structure (XAFS) analyses demonstrate that surface-anchored Ce atoms induce localized lattice distortion in Ce-SD-MnO 2 , generating synergistic surface defects and oxygen vacancies, while Ce-BD-MnO 2 merely causes non-active lattice expansion. First-principles calculations unveil that surface Ce O motifs optimally modulate the Mn d -band center, simultaneously enhancing charge density near the Fermi level and reducing *OOH adsorption energy. These atomic-level synergies empower Ce-SD-MnO 2 with exceptional ORR activity and durability. Implemented in Magnesium-air batteries, the surface-engineered catalyst delivers excellent performance: 120.7 mW cm −2 peak power density (46.3 % enhancement vs bulk-doped counterpart) and 98.5 % voltage retention after 11 h, establishing new stability benchmarks. This work provides fundamental insights into surface bond engineering for breaking the atomic efficiency-stability trade-off, offering a universal paradigm for designing energy conversion catalysts.
研究领域:
材料科学
·
电化学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 48
·19020-19034
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IF 3.069
Fu Yang,Shuying Gao,Yun Ding,Sheng Tang,Haifeng Chen,Jianjun Chen,Jianfeng Liu,Zhen Yang,Xiaocai Hu,Aihua Yuan
The confinement of refined catalytically active substances in special nanospaces is beneficial for promoting reaction processes by taking advantage of the quantum confinement effect and enlarged atomic efficiency. Herein, we present a redox nanoporous molecular sieve nanocatalyst containing size-confined active MnOx in the siliceous nanospace of mesopores via a functional micelle-assisted in situ embedding strategy. We also demonstrate its excellent environmental catalytic efficiency toward the oxidative degradation of methyl orange in the liquid phase (8 min) and volatile toluene in the gas phase (T90/T100 = 225/240 °C, under the mass space velocity of 60 000 ml g−1 h−1 and concentration of 1000 ppm, which surpass noble metal catalysts and most composite catalysts). This was achieved by virtue of eliminating diffusion limitations, and great active atom-efficiency. In this synthetic strategy, the well-made resultant MnOx had a refined size and greater interaction with diffusing reactant molecules without impeding their diffusion and mass transfer. Excellent and durable catalytic efficiency was demonstrated, due to the superior characteristics concerning the great dispersion of MnOx and favorable structure, thereby confirming that high catalytic removal efficiency depends on the amount of accessible MnOx rather than the loading of active species. Our findings provide the first example of a heterogeneous environmental catalyst that affords highly efficient catalytic elimination of organic contaminants in both liquid and gaseous systems.
研究领域:
环境科学
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材料科学
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催化化学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-11
·
IF 14.919
Wang Jinling,Dai Xingchao,Wang Hualin,Liu Honglai,Rabeah Jabor,Brückner Angelika,Shi Feng,Gong Ming,Yang Xuejing
Diminishing fossil fuel resources and calls for sustainability are driving the urgent need for efficient valorization of renewable resources with high atom efficiency. Inspired from the natural goethite mineral with Mn paragenesis, we develop cost-effective MnO 2 /goethite catalysts for the efficient valorization of dihydroxyacetone, an important biomass-based platform molecule, into value-added glycolic acid and formic acid with 83.2% and 93.4% yields. The DHA substrates first undergo C−C cleavage to selectively form glycolic acid and hydroxymethyl (·CH 2 OH) radicals, which are further oxidized into formic acid. The kinetic and isotopic labeling experiments reveal that the catalase-like activity of MnO 2 turns the oxidative radicals into oxygen, which then switches towards a hydroxymethyl peroxide (HMOO) pathway for formic acid generation and prevents formic acid over-oxidation. This nature-inspired catalyst design not only significantly improves the carbon efficiency to 86.6%, but also enhances the oxygen atom utilization efficiency from 11.2% to 46.6%, indicating a promising biomass valorization process.
研究领域:
化学工程
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催化
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可持续化学
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生物质转化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2023
·
IF 3.6
Shuo Li,Xian Xu,Qianlin Sun,Xin Xu
This work reports an intramolecular C(sp3)–H annulation of functionalized 2,6-lutidines catalyzed by an organocalcium hydride [{(DIPPnacnac)CaH(thf)}2] (DIPPnacnac = CH{(CMe)(2,6-iPr2–C6H3N)}2). This reaction constitutes a streamlined approach for producing a new family of tetrahydro-1,5-naphthyridines and hexahydropyrido[3,2-b]azocines derivatives in good to excellent yields with high atom efficiency and broad substrates scope. A calcium alkyl complex was isolated from the stoichiometric reaction between calcium hydride and the substrate through deprotonation, which was structurally characterized and confirmed as the catalytic intermediate.
研究领域:
有机化学
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催化
·
合成化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）