ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Xinxiang Chen,Huiqun Liu,Mingzhe Zhou,Guozhao Fang,Haimin Zhang,Zhenyang Cai,Xiaojun Zhao,Lairong Xiao,Sainan Liu,Yi Zhang
ABSTRACT Sodium-ion batteries (SIBs) are one of the most potential candidates for large-scale energy storage due to the low cost and eco-friendliness, however, a stable and reversible anode is urgently developed. In this work, a novel 2 × 2 tunnel-structured K 1.28 Ti 8 O 16 @N-doped carbon nanofibers (KTO@N CNFs) anode is successfully synthesized via simple electrospinning and subsequent thermal treatment with urea acted as the additional convenient nitrogen source. In-situ X-ray diffraction (XRD) measurement confirms the intercalation reaction mechanism and robust structure during Na + insertion/extraction. This composite material exhibits a reversible capacity of 116.4 mAh g − 1 at a current density of 100 mA g − 1 after 1000 cycles. More impressively, even at a high current density of 1 A g − 1 , the battery delivers capacity retention of 98.4 mAh g − 1 after 5000 cycles. The excellent electrochemical performance is attributed to the adequate 2 × 2 tunnel structure and the nano-confinement of N-doped nanofibers on K 1.28 Ti 8 O 16 nanocrystals, which offers enough diffusion paths and enhance the ionic diffusion of sodium ions. This work provides a facile strategy to synthesis stable, reversible, and long-cycle anode for sodium-ion batteries.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
CRYSTENGCOMM
·
2018
·Vol. 20
·期 8
·1151-1157
·
IF 3.304
Qiangwen Fan,Xiaowei Duan,Hong Yan
The solid state [2 + 2] photocycloaddition of N,N′-diacyl-1,4-dihydropyrazines has been investigated using thiourea as a template to preorient the reactants in the crystalline state in a manner that is beneficial for the [2 + 2] photocycloaddition. The structures of the photoadducts, syn-dimers and cage-dimers, were determined using NMR and single-crystal X-ray diffraction. According to the topochemical principles used to assess the feasibility of solid state photochemical [2 + 2] cycloaddition, topological analysis of cocrystals consisting of the N,N′-diacyl-1,4-dihydropyrazines and thiourea, as well as the syn-dimers, was performed to investigate the influence of packing modes and non-covalent interactions on their solid state photoreactivity. The results showed that the solid state [2 + 2] reactivities of both the N,N′-diacyl-1,4-dihydropyrazines assembled using thiourea and the syn-dimers were controlled by the topochemical orientation of the potentially reactive double bonds and the H-bonding interactions within the adjacent reactive molecules.
研究领域:
有机化学
·
光化学
·
晶体工程
·
超分子化学
·
药物合成
✓ 已验证
DOI
高影响因子
CORROSION
·
2013
·Vol. 69
·期 7
·672-680
·
IF 1.772
Jiang Y.Y.,Chen Y.,Ye Z.Y.,Chen H.,Zhang Z.,Zhang J.Q.,Cao C.N.
N-[2-[(2-aminoethyl) amino] ethyl]-9-octadecenamide (AAOA) has been synthesized in the lab, then tested as an effective and economic acid inhibitor for A3 steel in an acid medium with electrochemical techniques (electrochemical impedance and polarization curve). The results show that AAOA acts as a good mixed-type inhibitor for A3 steel in 1 M hydrochloric acid (HCl) solution, and the inhibition efficiency reaches 94% at the concentration of 200 mg/L. The corrosion current density of A3 steel increases with the increasing temperature from 20°C to 60°C. Meanwhile, Langmuir isotherm is found to provide the description of the adsorption behavior of AAOA, and the value of adsorption free energy (ΔG 0 ) is as low as low as −37.3 kJ/mol. One can assume the adsorption of inhibitor molecules on the metal surface is by chemisorption, which has been understood taking into account some other adsorption parameters (ΔH 0 , ΔS 0 ) and the activation parameters (E a , ΔH * , ΔG * ).
研究领域:
材料科学
·
腐蚀与防护
·
电化学
✓ 已验证
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2020
·Vol. 36
·期 5
·816-820
·
IF 1.063
Chu Ning,Xu Shuping,Xu Weiqing
Two different kinds of configurations of 1,4-bis[2-(4-pyridyl)ethenyl]-benzene( trans -bpeb and cis -bpeb) were achieved, and a bpeb dimer was synthesized in dimethyl sulfoxide(DMSO). Compared with the previous work that synthesized the bpeb dimer or polymer in crystal with a template agent needed, the reaction occurred in a solution phase in the present method. A hand-held ultraviolet lamp(365 nm) with the power of 12 W and the Watt density of 0.35 mW/cm 2 can realize the photodimerization of bpeb, instead of the high-power mercury lamp in most previous studies. Unlike other 2+2 cycloaddition in liquid state using catalysts even noble metals, no catalysts were required here, which is cost-saving. Only the trans -pbeb can start the cycloaddition and the formation of the close J-aggregations of trans -pbeb in DMSO is a precondition for explaining the 2+2 photodimerization. The productivity for the 2+2 cycloaddition product was achieved as 55.6%.
研究领域:
有机化学
·
光化学
·
超分子化学
·
材料化学
·
合成方法学
✓ 已验证
DOI
高影响因子
Journal of the American Chemical Society
·
2020
·
IF 14.612
Hai-Fang Li,Wenbo Cao,Xiaoxiao Ma,Xiaobo Xie,Yu Xia,Zheng Ouyang
The [2 + 2] photocycloaddition of alkenes and carbonyls is of fundamental interest and practical importance, as this process is extensively involved in oxetane-ring constructions. Although individual carbonyl group or alkene moiety has been utilized as photoactive species for oxetane formations upon ultraviolet photoexcitation, direct excitation of the entire noncovalent complex involving alkene and carbonyl substrates to achieve [2 + 2] photocycloadditions is rarely addressed. Herein, complexes with noncovalent interactions between benzophenone and C═C bonds in unsaturated lipids have been successfully characterized, and for the first time a [2 + 2] cycloaddition leading to the formation of oxetanes has been identified under visible-light irradiation. The mechanism of this reaction is distinctly different from the well-studied Paternò–Büchi reaction. The entire complexes characterized as dimeric proton-bonded alkene and carbonyl substrates can be excited under visible light, leading to electron transfer from the alkene moiety in fatty acyls to the carbonyl group within the complex. These results provide new insight into utilizing noncovalent complexes for the synthesis of oxetanes in which the excitation wavelength becomes independent of each individual substrate.
研究领域:
有机化学
·
光化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 27
·9252-9261
·
IF 6.4
Yuehong Luo,Kaijin Chen,Wenhui Wang,Ruxin Bei,Chuying Li,Yubo Long,Zhuxin Zhou,Siwei Liu,Zhenguo Chi,Jiarui Xu,Yi Zhang
A large Stokes-shifted fluorescent imide (HBTN-MC) and its related polyimides (HBHBTNms and HPHBTNms) were first designed and synthesized by introducing an excited state intramolecular proton transfer fluorophore 2-(2′-hydroxyphenyl)benzothiazole (HBT). The imide exhibited a large Stokes shift of 9654 cm−1 in the dichloromethane solution and 7648 cm−1 in the solid state. Based on the experimental and theoretical methods, the photophysical properties and the excited state intramolecular proton transfer (ESIPT) process of HBTN-MC have been systematically studied. The performances of the polyimides have been optimized by changing the alicyclic dianhydride and adjusting the copolymerization ratio. The as-prepared polyimide films retained the ESIPT performance with a large Stokes shift of larger than 8105 cm−1, a high photoluminescence quantum efficiency (φ) of 29%, decent colorless and transparency, high thermal performance (Td, 5% = 468 °C and Tg > 260 °C), and solubility in both conventional aprotic and protic solvents. In short, the newly developed imide and polyimides provide good examples for the development of ESIPT polymers with controllable emission wavelengths as well as high thermal, environmental, and radiation stability.
研究领域:
材料科学
·
聚合物化学
·
光学材料
·
荧光材料
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DOI
高影响因子
TEXTILE RESEARCH JOURNAL
·
2016
·
IF 1.299
Yangyi Chen,Jie An,Qi Zhong,Peter Müller-Buschbaum,Jiping Wang
The smart control of cotton fabric comfort by cross-linking thermo-responsive random copolymer is investigated. The monomers 2-(2-methoxyethoxy) ethoxyethyl methacrylate (MEO2MA) and ethylene glycol methacrylate (EGMA) with a molar ratio of 17:3 are selected to synthesize the thermo-responsive random copolymer poly(2-(2-methoxyethoxy) ethoxyethyl methacrylate-co-ethylene glycol methacrylate), abbreviated as P(MEO2MA-co-EGMA). By using citric acid as a cross-linking agent, the obtained P(MEO2MA-co-EGMA) is successfully immobilized onto cotton fabrics. Smart control is achieved from the thermo-responsive behavior of the copolymer. Cross-linked P(MEO2MA-co-EGMA) will collapse when the ambient temperature exceeds its transition temperature. Therefore, the formerly compact P(MEO2MA-co-EGMA) layer will switch to a porous structure, and the air/moisture permeability of the textiles is enhanced. As the comfort of the textiles is closely related to the air/moisture permeability, a smart control of the cotton fabric comfort can be realized. In addition, the softness of cotton fabrics with and without thermo-responsive polymers does not show a prominent change, even when the applied solution concentration is as high as 16% (wt%). On the contrary, the stiffness of the cotton fabric coated with poly(N-isopropylacrylamide) (PNIPAM) is significantly higher than the original cotton fabric, indicating that homo PNIPAM is less suitable for textiles used in daily lives. Moreover, the whiteness and mechanical properties are studied and stay unchanged after cross-linking. As a consequence, the introduction of P(MEO2MA-co-EGMA) into textiles can provide textiles with smart control of cotton comfort, and it will not influence the wearabilities of the textiles.
研究领域:
纺织科学
·
聚合物化学
·
材料科学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2020
·
IF 4.613
Yujie Zhang,Xinjiang Shi,Sixuan Xiao,Debao Xiao
Electrochromic devices (ECDs) which able to absorb the solar spectrum of visible (400–780 nm) and infrared (780–2000 nm) have attracted considerable attention due to the light control and energy-saving properties. In this paper, a electrochromic derived derivative of viologens, bis (2-(2-(2-hydroxyethoxy)ethoxy)ethyl) viologen bromide (HEV 2+ 2Br − ) was successfully synthesized and added to novel environmentally benign hydrogel electrolytes containg deionized water , sodium carboxymethyl chitosan and vitamin C (as electron mediators for the first time) as an electrochromic chromophore . The electrochromic devices on the basic of electrochromic materials (HEV 2+ 2Br − ) and hydrogel electrolytes underwent reversible switching between colorlessness and deep purple hues upon the potential ranges from 0 V to −1.2 V. Spectroelectrochemical studies demonstrated that HEV-based gel devices showed exceptional electrochromic behaviors with low driving voltage of −0.80 V, satisfactory optical contrast (unambiguously exceeded 64.13%) and high coloration efficiency (up to 243 cm 2 /C at 520 nm and 119 cm 2 /C at 865 nm) in the visible and infrared radiation. In consideration of their good electrochromic performance and environmentally friendly properties of benign hydrogel electrolytes containing HEV, the HEV-based gel devices have brilliant potentialities as candidates for related electrochromic applications for energy-efficient architecture.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
Sustainable Energy & Fuels
·
2019
·Vol. 4
·期 2
·911-920
·
IF 4.912
Junjian Xie,Xiangwen Zhang,Chengxiang Shi,Lun Pan,Fang Hou,Genkuo Nie,Jiawei Xie,Qing Liu,Ji-Jun Zou
Hydrocarbons with a highly strained four-membered ring are synthesized via self-photosensitized [2 + 2] cycloaddition and hydrodeoxygenation using cyclohexene and isophorone as feedstocks, which show high density and high heat values. Photoreaction can take place selectively with isophorone as a self-sensitizer and a reactant. Isophorone/cyclohexene co-cycloaddition has a much faster reaction rate than self-cycloaddition of isophorone, and both DFT calculations and photochemical kinetics show that the energy barrier for the former is much lower than that for the latter. Under optimal conditions, the selectivity of co-cycloaddition and self-cycloaddition can reach 93.3% and 94.9%, with isophorone conversion of 95.4% and 68.8%, respectively. In addition, a series of olefins can undergo self-photosensitized [2 + 2] cycloaddition with isophorone smoothly in high selectivity. After hydrodeoxygenation, hydrocarbons derived from isophorone/cyclohexene mixture and pure isophorone (with an overall yield of 82.1% and 61.3%) have high densities of 0.903 g mL−1 and 0.892 g mL−1, respectively, along with good cryogenic properties. Especially, the hydrocarbons synthesized through photosensitized cycloaddition show considerably higher density and heat values compared with those derived from a common C–C coupling route, which is attributed to the constructed strained cyclic structures. This work provides a new way for photosynthesis of high-energy-density hydrocarbons.
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产品关联
DOI
高影响因子
TETRAHEDRON
·
2017
·
IF 2.651
Ling-Ling Wu,Gao H. Yang,Zhi Guan,Yan-Hong He
The Rose Bengal sensitized intermolecular [2 + 2]-cycloaddition of 3-ylideneoxindoles for the synthesis of spirocyclic oxindoles was developed successfully under visible light irradiation conditions. The cycloaddition products were obtained in good yields (up to 93%) with excellent diastereoselectivity and regioselectivity by using a low loading of Rose Bengal (0.125 mol%) as a triplet sensitizer. This work demonstrates the potential benefits of Rose Bengal in visible light catalysis.
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产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2025
·
IF 3.7
Jinbo Ouyang,Longping Jiang,Jiayao Li,Feiqiang He,Zhi Gao,Mengmeng Wang,Limin Zhou,Zongbo Xie,Zhiqiang Zhu,Yifu Chen
Graphical Three isomeric fluorinated acylhydrazone derivatives (DFBP-IND, DFBP-BHD, DFBP-3-FBHD) were successfully synthesized and demonstrated dynamic photo-responsive behavior ranging from crack initiation to crystal fragmentation under 365 nm UV irradiation. The photochemical mechanism was explored in detail and highlighted the essential role of the C═N bond in the acylhydrazone framework for enabling [2+2] cycloaddition-driven actuation. Our structural engineering strategy established a design paradigm for photoresponsive materials through rational selection of hydrazide precursors, enabling precise modulation of optomechanical properties. Crystalline materials with photomechanical responsiveness have garnered significant attention in flexible actuators and micro/nano-electromechanical systems due to their unique capability to directly convert light into mechanical energy. In this work, four novel fluorinated acylhydrazone compounds were successfully synthesized through direct condensation reactions between 4,4′-difluorobenzophenone (DFBP) and acylhydrazine compounds, including benzoylhydrazine (BHD), 3-fluorobenzoylhydrazine (3-FBHD), isoniazid (IND), and acetylhydrazine (AED). Systematic investigation of their photomechanical responses revealed distinct molecular mechanisms. Experimental results demonstrate that isomeric fluorinated acylhydrazone derivatives (DFBP-BHD, DFBP-3-FBHD, DFBP-IND) exhibit dynamic photo-responsive behavior ranging from crack initiation to crystal fragmentation under 365 nm UV irradiation, whereas the hydrazone derivative DFBP-AED remains inert. This confirms the essential role of [2 + 2] photocycloaddition-dependent C = N double bonds in photomechanical activity. Comprehensive characterization through DSC, TG, XRD, ¹H/¹ 3 C NMR, and MS elucidated the formation pathways and structural characteristics of photocycloaddition products. Density functional theory calculations revealed that energy disparities between (0 0 1) and (1 0 0) crystallographic planes govern longitudinal fragmentation patterns. This study establishes a “molecular structure-crystal arrangement-macroscopic response” multi-scale regulation strategy, offering novel insights for developing high-performance light-driven materials.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FITOTERAPIA
·
2024
·
IF 2.5
Yuan Wei,Wen-Hua Dong,Wei Li,Jun Zeng,Hui-Qin Chen,Sheng-Zhuo Huang,Li Yang,Wen-Li Mei,Ya-Li Wang,Zhi-Yong Guo,Hao-Fu Dai,Hao Wang
Six new dimeric 2-(2-phenylethyl)chromones ( 1 – 6 ) were successfully isolated from the ethanol extract of agarwood of Aquilaria filaria from Philippines under HPLC-MS guidance. Compounds 1 – 6 are all dimers formed by linking 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromone and flindersia 2-(2-phenylethyl)chromone via a single ether bond, and the linkage site (C5-O-C8′′) of compound 2 is extremely rare. A variety of spectroscopic methods were used to ascertain their structures, including extensive 1D and 2D NMR spectroscopic analysis, HRESIMS, and comparison with literature. The in vitro tyrosinase inhibitory and anti-inflammatory activities of each isolate were assessed. Among these compounds, compound 2 had a tyrosinase inhibition effect with an IC 50 value of 27.71 ± 2.60 μM, and compound 4 exhibited moderate inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with an IC 50 value of 35.40 ± 1.04 μM.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）