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Insights into the Active Acid Sites for Isosorbide Synthesis from Renewable Sorbitol and Cellulose on Solid Acid Catalysts

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Chemical Research in Chinese Universities 2022年第1期38卷 257-264页

作者： DENG Tianyin HE Xiaohui liu haichao Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871P.R.China

Sustainable synthesis of isosorbide, an important renewable platform chemical, from sorbitol and cellulose, has attracted increasing attention, but still remains challenging. Here, we have studied the effects of the acidity on the dehydration of sorbitol in water on a variety of solid acids, including zeolites, sulfonic materials, montmorillonite and mixed SiO2-Al2O3 oxide. These solid acids showed markedly different activities, which were found to be closely related to their strong Brønsted acid sites, while the weak Brønsted acid and Lewis acid sites were essentially inactive. Different from the other solid acids examined, H-ZSM-5 zeolites in a wide range of Si/Al molar ratios(25-300) exhibited superior selectivities to isosorbide in dehydration of sorbitol, consistent with the observed difference in their formation rates of the 1,4-sortbitan and 3,6-sorbitan intermediates. Kinetic studies on the sorbitol dehydration showed that 3,6-sorbitan, once it formed, dehydrated to isosorbide more readily than 1,4-sorbitan by a factor of 19, and the formation rate constant of 3,6-sorbitan on H-ZSM-5(Si/Al=25) was about three times higher than that of H-Beta(Si/Al=25). Such favorable formation of the reactive 3,6-sorbitan intermediate and the higher isosorbide selectivity on H-ZSM-5 appear to be induced by its confined pore structure composed of the paired 5-membered rings. H-ZSM-5 was also found to be efficient for the direct conversion of cellulose to isosorbide in coupling with Ru/C hydrogenation catalyst. This work provides fundamental insights into the acidity and pore structures that are helpful for the design of novel solid acids toward the efficient synthesis of isosorbide from the dehydration of sorbitol and even directly from the tandem reaction of cellulose.

关键词： Cellulose Isosorbide Solid acid Strong Brønsted acid Pore structure H-ZSM-5

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Tribological study of two ammonium chloride-decanoic acid deep eutectic solvents(DESs)as high-performance lubricants

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Friction 2024年第11期12卷 2441-2457页

作者： Zhuocheng LI Enhui ZHANG Weimin LI haichao liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Zibo Innovation Center of High-End Synthetic Lubricating Materials Zibo 255000China

Deep eutectic solvents(DESs)are acknowledged as a novel class of functional *** share similar physical properties with ionic liquids(ILs)and have the potential to be a novel class of *** this study,two DESs,namely tetrabutylammonium chloride-decanoic acid DES(C4-DES)and methyl tricaprylmethylammonium chloride-decanoic acid DES(C8-DES),were synthesized,and their physico-chemical properties and tribological performances were ***-analysis of the rubbing surfaces used multiple techniques to gain insights into the lubrication *** show that the coefficient of friction(COF)and wear were reduced by approximately 29%and 91%for the C4-DES,and 36%and 94%for the C8-DES,compared to an ester base *** friction reduction behavior of the DESs is attributed to the monolayer adsorption of the polar group in the decanoic acid(DEAC),whose effectiveness is affected by the component of the ammonium salts in the DESs and the operating *** addition to the adsorbed film,worn surface analysis revealed that an ultra-thin tribochemical film with a thickness of 3–7 nm was formed on the surfaces lubricated with the *** composition of the film was studied,and the lubrication mechanisms of the two DESs were discussed.

关键词： deep eutectic solvent(DES) lubricants tribological performance boundary lubrication

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Efficient aerobic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid on Ru/C catalysts

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Science China Chemistry 2017年第7期60卷 950-957页

作者： Lufan Zheng Junqi Zhao Zexue Du Baoning Zong haichao liu Research Institute of Petroleum Processing SINOPEC Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable SpeciesCollege of Chemistry and Molecular Engineering Peking University

2,5-Furandicarboxylic(FDCA) is a potential substitute for petroleum-derived terephthalic acid, and aerobic oxidation of5-hydroxymethylfurfural(HMF) provides an efficient route to synthesis of FDCA. On an activated carbon supported ruthenium(Ru/C) catalyst(with 5 wt% Ru loading), HMF was readily oxidized to FDCA in a high yield of 97.3% at 383 K and 1.0 MPa O_2 in the presence of Mg(OH)_2 as base additive. Ru/C was superior to Pt/C and Pd/C and also other supported Ru catalysts with similar sizes of metal nanoparticles(1–2 nm). The Ru/C catalysts were stable and recyclable, and their efficiency in the formation of FDCA increased with Ru loadings examined in the range of 0.5 wt%–5.0 wt%. Based on the kinetic studies including the effects of reaction time, reaction temperature, O_2 pressure, on the oxidation of HMF to FDCA on Ru/C, it was confirmed that the oxidation of HMF to FDCA proceeds involving the primary oxidation of HMF to 2,5-diformylfuran(DFF) intermediate, and its sequential oxidation to 5-formyl-2-furancarboxylic acid(FFCA) and ultimately to FDCA, in which the oxidation of FFCA to FDCA is the rate-determining step and dictates the overall formation rate of FDCA. This study provides directions towards efficient synthesis of FDCA from HMF, for example, by designing novel catalysts more efficient for the involved oxidation step of FFCA to FDCA.

关键词： aerobic oxidation 5-hydromethylfurfural 2 5-furandicarboxylic supported Ru catalyst base additives reaction mechanism

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The density matrix picture of laser coherent control current

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Science China(Physics,Mechanics & Astronomy) 2004年第2期47卷 231-243页

作者： SHOU Qian ZHANG haichao liu Luning LIN Weizhu State Key Laboratory of Optoelectronic Materials and Technologies Zhongshan (Sun Yat-Sen) UniversityGuangzhou 510275 China State Key Laboratory of Optoelectronic Materials and Technologies Zhongshan (Sun Yat-Sen) UniversityGuangzhou 510275 China State Key Laboratory of Optoelectronic Materials and Technologies Zhongshan (Sun Yat-Sen) UniversityGuangzhou 510275 China State Key Laboratory of Optoelectronic Materials and Technologies Zhongshan (Sun Yat-Sen) UniversityGuangzhou 510275 China

The physical substance of the coherent control current and the optical rectification have been analyzed based on density matrix perturbation theory. The analytical results demonstrate that they arise from the real and virtual manifestations of the same nonlinear process associated with diagonal and non-diagonal density matrix. And in terms of polarization, they respectively arise from the intraband and interband polarizations. Both the evolution of the coherent control current exited by ultrafast laser pulse and its dependence on frequency have been studied in time and frequency domains. In order to get an explicit knowledge of intraband polarization and the origination of the coherent control current, we have investigated the initial photo-carriers momentum distribution. The ultrafast decay of the polar momentum population in order of tens of femtosends is given to illustrate its instantaneous optical response.

关键词： density matrix, Feynman diagrams, coherent control current, intraband polarization.

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Recyclable Cu Salt-Derived Brønsted Acids for Hydrolytic Hydrogenation of Cellulose on Ru Catalyst

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CCS Chemistry 2022年第9期4卷 3162-3169页

作者： Yue liu Linxiao Chen Wei Zhang haichao liu Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871

Brønsted acid-catalyzed hydrolysis of cellulose,the most abundant source of biomass in nature,is the critical step for its depolymerization and subsequent conversion to sugar alcohols and other important *** acids are... 详细信息

关键词： cellulose recyclable Brønsted acids hydrolysis sugar alcohols sorbitol insoluble copper salt

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Insights into support effects on Ce-Zr-O mixed oxide-supported gold catalysts in CO oxidation

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Journal of Energy Chemistry 2013年第1期22卷 98-106页

作者： Hongpeng Zhang haichao liu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species College of Chemistry and Molecular Engineering Peking University

Au]Cel_xZrxO2 catalysts （x = 0-0.8） were prepared by a deposition-precipitation method using Cel_xZrxO2 nanoparticles as supports with variable Ce and Zr contents. Their structures were characterized by complimentary means such as X-ray diffraction, Raman, scanning trans- mission electron microscopy and X-ray photoelectron spectroscopy （XPS）. These Au catalysts possessed similar sizes and crystalline phases of Cel_xZrzO2 supports as well as similar sizes and oxidation states of Au nanoparticles. The oxidation state of Au nanoparticles was dominated by Au~ especially in CO oxidation. Their activities were examined in CO oxidation at different temperatures in the range of 303-333 K. The CO oxidation rates normalized per Au atoms increased with the increasing Ce contents, and reached the maximum value over Au/CeO2. Such change was in parallel with the change in the oxygen storage capacity values, i.e. the amounts of active oxygen species on Au/Cel_zZrzO2 catalysts. The excellent correlation between the two properties of the catalysts suggests that the intrinsic support effects on the CO oxidation rates is related to the effects on the adsorption and activation of O2 on Au/Cel_xZrxO2 catalysts. Such understanding on the support effects may be useful for designing more active Au catalysts, for example, by tuning the redox properties of oxide supports.

关键词： gold catalyst ceria-zirconia support CO oxidation oxygen storage capacity support effect

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Critical approaches in the catalytic transformation of sugar isomerization and epimerization after Fischer-History,challenges,and prospects

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Green Energy & Environment 2024年第3期9卷 435-453页

作者： Da-Ming Gao Xun Zhang haichao liu Hidemi Fujino Tingzhou Lei Fuan Sun Jie Zhu Taoli Huhe National-local Joint Engineering Research Center of Biomass Refine and High-Quality Utilization Changzhou UniversityChangzhou213164China Institute of Urban and Rural Mining Research Changzhou UniversityChangzhou213164China Changzhou Key Laboratory of Biomass Green Safe&High Value UtilizationChangzhou UniversityChangzhou213164China Beijing National Laboratory for Molecular Science College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Department of Rehabilitation Science Kobe University Graduate School of Health SciencesKobe654-0142Japan

The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and the synthesis of ***,high-fructose corn syrup(HFCS)is industrially produced in more than 10 million tons annually using immobilized glucose *** low-calorie saccharides such as tagatose and psicose,which are becoming popular sweeteners,have also been produced on a pilot scale in order to replace sucrose and ***,current catalysts and catalytic processes are still difficult to utilize in biomass conversion and also have strong substrate dependence in producing high-value,rare *** the specific reaction properties of saccharides and catalysts,since the pioneering discovery by Fischer,various catalysts and catalytic systems have been discovered or developed in attempts to extend the reaction pathways,improve the reaction efficiency,and to potentially produce commercial *** this review,we trace the history of sugar isomerization/epimerization reactions and summarize the important breakthroughs for each reaction as well as the difficulties that remain unresolved to date.

关键词： Rare sugars Isomerization Ketonization Epimerization Catalytic transformation

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Hydroxyl radicals-mediated oxidative cleavage of the glycosidic bond in cellobiose by copper catalysts and its application to low-temperature depolymerization of cellulose

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Chinese Journal of Catalysis 2020年第7期41卷 1073-1080页

作者： Fangwei Gu haichao liu Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

As the most abundant source of biomass in nature for sustainable production of fuels and chemicals,efficient depolymerization of cellulose under mild conditions,due to the difficulty in selective cleavage of itsβ-1,4-glycosidic bonds,still remains ***,we report a novel method for oxidative cleavage of the glycosidic bonds by free *** by the cellobiose reaction,it was found that·OH radicals,generated from the decomposition of H2O2 catalyzed by CuSO4 or CuO/SiO2,were efficient for selective conversion of cellobiose to glucose and gluconic acid at a low temperature of 333 K,and their selectivities reached 30.0%and 34.6%,respectively,at 23.4%cellobiose *** radicals,such as·SO4?,also exhibited high efficacy in the cellobiose *** studies suggest that the oxidative cleavage of theβ-1,4-glycosidic bond by the free radicals involve formation of the carbon radical intermediate via abstraction of the H atom dominantly at the C1 *** this oxidative mechanism,treatment of microcrystalline cellulose with·OH by impregnation with H2O2 and CuSO4 catalyst at 343 K led to significant enhancement in its hydrolysis *** results demonstrate the effectiveness of this new method in the oxidative cleavage of glycosidic bonds,and its viability for the efficient depolymerization of cellulose at low temperatures,which can be further improved,for example,by exploring new free radicals and optimizing their reactivity and selectivity.

关键词： Cellulose depolymerization Cellobiose Hydroxyl radical Oxidative cleavage Glycosidic bond

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Towards high performance polyimide cathode materials for lithium–organic batteries by regulating active-site density,accessibility,and reactivity

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eScience 2024年第4期4卷 110-119页

作者： Jun Wang haichao liu Chunya Du Bing liu Haoran Guan Yu liu Shaowei Guan Zhenhua Sun Hongyan Yao National&Local Joint Engineering Laboratory for Synthesis Technology of High Performance Polymer Key Laboratory of High Performance PlasticsMinistry of EducationCollege of ChemistryJilin UniversityChangchun 130012China State Key Lab of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016China College of Sciences Shenyang University of Chemical TechnologyShenyang 110142China

Organic carbonyl electrode materials offer promising prospects for future energy storage systems due to their high theoretical capacity,resource sustainability,and structural *** much progress has been made in the research of high-performance carbonyl electrode materials,systematic and in-depth studies on the underlying factors affecting their electrochemical properties are rather ***,five polyimides containing different types of diamine linkers are designed and synthesized as cathode materials for Li-ion ***,the incorporation of carbonyl groups increases the active-site density in both conjugated and non-conjugated ***,increased molecular rigidity can improve the accessibility of the active ***,the introduction of the conjugated structure between two carbonyl groups can increase the reactivity of the active ***,the incorporation of carbonyl structures and conjugated structures increases the capacity of ***,PAN,PMN,PSN,and PBN exhibit 212,198,199,151,and 115mAh g^(−1)at 50mAg^(−1),*** addition,the introduction of a carbonyl structure and a conjugated structure is also beneficial for improving cycling stability and rate *** work can deepen the understanding of the structure–function relationship for the rational design of polyimide electrode materials and can be extended to the molecular design of other organic cathode materials.

关键词： Organic cathode materials Polymer electrode Lithium-ion batteries Carbonyl Polyimides

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Enhanced deep-red emission in donor-acceptor molecular architecture:The role of ancillary acceptor of cyanophenyl

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Chinese Chemical Letters 2019年第11期30卷 1947-1950页

作者： Yue Shen Xiaohui Tang Yuwei Xu haichao liu Shitong Zhang Bing Yang Yuguang Ma State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640China

Organic solid-state luminescent materials with high-efficiency deep-red emission have attracted considerable interest in recent *** donor-acceptor(D-A)type molecules has been one of most commonly used strategies to achieve deep-red emission,but it is always difficult to achieve high photoluminescence(PL)quantum yield(ηPL)due to forbidden charge-transfer ***,we report a new D-A type molecule 4-(7-(4-(diphenylamino)phenyl)-9-oxo-9H-fluoren-2-yl)benzonitrile(TPAFOCN),deriving from donor-acceptor-donor(D-A-D)type 2,7-bis(4-(diphenylamino)phenyl)-9H-fluoren-9-one(DTPA-FO)with a fluorescence maximum of 627 nm in *** molecular design enables a transformation of acceptor from fluorenone(FO)itself to 4-(9-oxo-9H-fluoren-2-yl)benzonitrile(FOCN).Compared with DTPA-FO,the introduction of cyanophenyl not only shifts the emission of TPA-FOCN to deep red with a fluorescence maximum of 668 nm in solids,but also maintains the highηPL of 10%.Additionally,a solution-processed non-doped organic light-emitting diode(OLED)was fabricated with TPA-FOCN as ***-FOCN device showed a maximum luminous efficiency of 0.13 cd/A and a maximum external quantum efficiency(EQE)of 0.22%with CIE coordinates of(0.64,0.35).This work provides a valuable strategy for the rational design of high-efficiency deep-red emission materials using cyanophenyl as an ancillary acceptor.

关键词： Deep-red emission Fluorenone Cyanophenyl group Donor-acceptor Organic light-emitting diodes

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