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Role of methoxy and C_(α)-based substituents in electrochemical oxidation mechanisms and bond cleavage selectivity of β-O-4 lignin model compounds

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green Energy & Environment 2024年第1期9卷 114-125页

作者： Yang Zhou Qiang Zeng Hongyan He Kejia Wu Fuqiao Liu Xuehui Li School of chemistry and Chemical Engineering The Guangdong Provincial Key Laboratory of Green Chemical Product TechnologyState Key Laboratory of Pulp and Paper EngineeringSouth China University of TechnologyGuangzhouGuangdong510640China CAS key laboratory of green process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China

In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations.

关键词： Lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms Substituent effect

Redox-Active Dihydrophenazine-Based Macrocycle:Synthesis,Conformation-Adaptive Behavior and Host-Guest Complexation with Tetracyanoquinodimethane

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Chinese Journal of chemistry 2024年第16期42卷 1895-1900页

作者： Qiong-Yan Hong Bin Huang Meng-Xiang Wu Lin Xu Xiao-Li Zhao Xueliang Shi Hai-Bo Yang shanghai key laboratory of green chemistry and Chemical processes State Key Laboratory of Petroleum Molecular&Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal University3663 N.Zhongshan RoadShanghai 200062China

A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and *** the one hand,the macrocycle showed host-guest interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between ***,host-guest complexation was accompanied by fluorescence quenching and conformational change of the *** the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the guest molecule TCNQ,thereby accomplishing reversible binding ***,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-guest chemistry.

关键词： Dihydrophenazine Macrocycle Conformational adaptation Redox-active Host-guest interactions Charge transfer interaction Organic radical Supramolecular chemistry

Application of surfactant for improving leaching process of weathered crust elution-deposited rare earth ores

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Journal of Rare Earths 2024年第1期42卷 181-190,I0007页

作者： Fang Zhou Lisen Zhang Zhiwei Wang Yixin Zhang Ru'an Chi Xiaoyan Wu key laboratory for green Chemical process of Ministry of Education Wuhan Institute of TechnologyWuhan430073China

Weathered crust elution-deposited rare earth ores(WREOs)in China are the main source of medium and heavy rare earths in the *** order to improve the seepage and the mass transfer of traditional ammonium salt leaching process of WREOs,surfactants were added in the ammonium sulfate leaching solution and the ammonium chloride leaching *** leaching kinetics,the mass transfer process,and the adhesion work reduction factor calculated from the interfacial properties were studied to reveal the strengthening mechanism of *** the presence of the tested five surfactants,cetyl trimethyl ammonium bromide(CTAB),dodecyl trimethyl ammonium bromide(DTAB),sodium dodecyl sulfate(SDS),sodium oleate and oleic acid,the permeability of WREOs is improved,the rare earth(RE)leaching efficiency increase and the impurity aluminum(Al)leaching efficiency decrease,indicating its promotional effect on the leaching process of ***,CTAB shows a better leaching enhancement,and the optimal addition dosage is 0.4 g/L for the two ammonium salt leaching agent *** kinetics analysis shows the internal diffusion controls model of RE and Al leaching process,and the leaching kinetics equations of RE and Al related to CTAB concentration were obtained for the two ammonium salt leaching *** to the chromatographic plate theory,the mass transfer efficiency of RE increases with the CTAB concentration increasing until 0.4 g/L,which confirms that the optimal CTAB addition is 0.4 g/*** adhesion work and adhesion work reduction factor indicate more favorable permeation as well as the leaching process.

关键词： Weathered crust elution-deposited rare earth ores Surfactant Kinetics Mass transfer

Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： Siyue Wang Jinhong Li Qingxin Xu Shengjie Song Yu'ni Jiang Lidong Chen Xin Shi Weiguo Cheng Faculty of chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China Beijing key laboratory of Ionic Liquids Clean process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous ***,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce *** results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore *** then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion *** acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid *** a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB *** catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with *** present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

Long‐life lithium batteries enabled by a pseudo‐oversaturated electrolyte

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Carbon Energy 2024年第4期6卷 115-127页

作者： Youchun Yu Simeng Wang Juyan Zhang Weiwei Qian Nana Zhang Guangjie Shao Haiyan Bian Yuwen Liu Lan Zhang Hebei key laboratory of Applied chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdaoChina Beijing key laboratory of Ionic Liquids Clean process CAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijingChina Haike Group Research Institute of Innovation&Technology DongyingChina Langfang green Industrial Technology Center LangfangChina

The specific energy of Li metal batteries(LMBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging for the liquid ***,a novel pseudo‐oversaturated electrolyte(POSE)is prepared by introducing 1,1,2,2‐tetrafluoroethyl‐2,2,3,3‐tetrafluoropropyl ether(TTE)to adjust the coordination structure between diglyme(G2)and lithium bis(trifluoromethanesulfonyl)imide(LiTFSI).Surprisingly,although TTE shows little solubility to LiTFSI,the molar ratio between LiTFSI and G2 in the POSE can be increased to 1:1,which is much higher than that of the saturation state,1:*** and experimental results prove that TTE promotes closer contact of the G2 molecular with Li^(+)in the ***,it also participates in the formation of electrolyte/electrode *** electrolyte shows outstanding compatibility with both the Li metal anode and typical high‐voltage ***||Li symmetric cells show a long life of more than 2000 h at 1 mA cm^(−2),1 mAh cm^(−2).In the meantime,Li||LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cell with the POSE shows a high reversible capacity of 134.8 mAh g^(−1 )after 900 cycles at 4.5 V,1 C *** concept of POSE can provide new insight into the Li^(+)solvation structure and in the design of advanced electrolytes for LMBs.

关键词： high voltage lithium metal batteries pseudo‐oversaturated electrolyte solid electrolyte interphases(SEI) solvation structure

Current collectors' effects on the electrochemical performance of LiNi0.6Co0.2Mn0.2O2 suspension electrodes for lithium slurry battery

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green Energy & Environment 2024年第8期9卷 1306-1313页

作者： Linshan Peng Yufei Ren Zhaoqiang Yin Zhitong Wang Xiangkun Wu Lan Zhang CAS key laboratory of green process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences School of Chemical Engineering University of Chinese Academy of Sciences Hefei University Institute of Mechanics Chinese Academy of Sciences Langfang green Industrial Technology Center

Take after the advantages of lithium-ion battery（LIB） and redox flow battery（RFB）, semi-solid flow battery（SSFB） is a promising electrochemical energy storage device in renewable energy utilization. The flowable slurry electrode realizes decouple of energy and power density,while it also brings about new challenge to SSFBs, electron transport between active material and the out circuit. In this consideration, three types of current collectors（CCs） are applied to study the resistance and electrochemical performances of slurry cathodes within pouch cells for the first time. It proves that the electronic resistance（Re） between slurry electrode and the CC plays a decisive role in SSFB operation, and it is so large when Al foil is adopted that the cell cannot even work. Contact angle between Ketjen black（KB） slurry without active material（AM） and the CC is a preliminarily sign for the Re, the smaller the angle, the lower the resistance, and the better electrochemical performance of the cell.

关键词： Semi-solid flow battery Slurry electrode Current collector Electronic resistance Carbon coated Al

Selective cyclohexane oxidation enhancement by electronic structures regulation of metal-poly(ionic liquid)s

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green Chemical Engineering 2024年第2期5卷 213-221页

作者： Ying Jin Shengxin Chen Ruirui Wang Yumei Liu Xinxin Li Yingwei Li Ruirui Zhang Ruixia Liu Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou450001China Beijing key laboratory of Ionic Liquids Clean process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringInnovation Academy for Green ManufactureCASBeijing100190China

Poly(ionic liquids)(PILs)combined with the macromolecular structure and unique properties of ionic liquids show unlimited potential in *** this work,a series of metal-based PIL with different ionic ratios were prepared for the selective oxidation of *** analysis reveals that different degrees of ionization could adjust the Co-N sites of the catalysts efficiently,leading to significant changes in their electronic structure,which strongly relate to catalytic performance in oxidation.20.07%cyclohexane conversion and 13.06%cyclohexanone and cyclohexanol(KA oil)yield can be achieved by metal-based PILs that are better than other commercial *** with CoCl_(2),metal-based PILs perform well,with superior conversion and KA oil *** interestingly,the catalyst created in this study features a malleable Co-N site,which may potentially have an impact on how oxygen species adsorb and desorb from the ***,the catalyst studied in this work is used as molecular oxygen for the selective oxidation of cyclohexane to produce KA oil,and its application prospect is promising.

关键词： Metal-PILs Cyclohexane oxidation C-H activation Co-N sites

Selective oxidation using in-situ generated hydrogen peroxide over titanosilicates

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Chinese Journal of Structural chemistry 2024年第6期43卷 12-14页

作者： Zhipeng Wan Hao Xu Peng Wu State key laboratory of Petroleum Molecular&process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China Institute of Eco-Chongming Shanghai202162China

Titanosilicates are a class of heteroatom-containing zeolitic materials with tetrahedrally coordinated Ti^(4+)ions incorporated into crystalline zeolite frameworks,with TS-1,Ti-MWW and Ti-MOR as representative and attractive selective oxidation *** liquid-phase oxidations of a variety of substrates such as olefins and ketones with the green oxidant of H_(2)O_(2)over titanosilicates under mild conditions have attracted considerable research interests in the clean production of fine and bulk chemicals,among which propylene epoxidation and cyclohexanone ammoximation have been industrialized[1].

关键词： silicate zeolite propylene

Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers

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green Energy & Environment 2024年第9期9卷 1336-1365页

作者： Kaili Wang Tingting Zhou Zhen Cao Zhimin Yuan Hongyan He Maohong Fan Zaiyong Jiang School of chemistry & Chemical Engineering and Environmental Engineering Weifang University Beijing key laboratory of Ionic Liquids Clean process State Key Laboratory of Multiphase Complex Systems CAS Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences College Engineering and Physical Sciences and School of Energy Resources University of Wyoming

The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future.

关键词： PEMFC 3D ordered electrode Structural features Preparation technology Ultralow Pt loading