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Science China Chemistry 2017年第9期60卷 1212-1218页

作者： Xiaodong Wei Lulu Bu Weiqiang Tang shuangliang zhao Yongshu Xie Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chem&try and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Two fluorescence "turn-on" Zn^(2+) probes were developed by introducing an anthracenyl fluorophore through the linkage of a diphenylamino moiety at the 5-position of a dipyrrin ***,two compounds with weak fluorescence were designed,synthesized,and employed as CHEF(chelation enhanced fluorescence) type fluorescence "turn-on" Zn^(2+) probes,which exhibit dramatic fluorescence enhancement upon addition of Zn^(2+),showing high sensitivities and impressive detection limits of 13 and12 nM,respectively,better than their analogues containing simple aryl substituents at the 5 positions of a di-or tripyrrin *** addition,both of the probes exhibit good selectivity,short response time of less than 10 s and wide applicable pH ***,the weak fluorescence nature of the probes was rationalized based on viscosity dependence measurements and theoretical *** results provide further insight into the development of selective and sensitive zinc probes.

关键词： fluorescent probes, zinc probes, chelation enhanced fluorescence, sensitivity

Solvent effects on Diels-Alder reaction in ionic liquids:A reaction density functional study

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Chinese Journal of Chemical Engineering 2024年第2期66卷 180-188页

作者： Zijiang Dou Weiqiang Tang Peng Xie shuangliang zhao Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Extensive experimental studies have been performed on the Diels-Alder(DA)reactions in ionic liquids(ILs),which demonstrate that the IL environment can significantly influence the reaction rates and ***,the underlying microscopic mechanism remains *** this work,the multiscale reaction density functional theory is applied to explore the effect of 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM][PF_(6)])solvent on the reaction of cyclopentadiene(CP)with acrolein,methyl acrylate,or *** analyzing the free energy landscape during the reaction,it is found that the polarization effect has a relatively small influence,while the solvation effect makes both the activation free energy and reaction free energy *** addition,the rearrangement of local solvent structure shows that the cation spatial distribution responds more evidently to the reaction than the anion,and this indicates that the cation plays a dominant role in the solvation effect and so as to affect the reaction rates and selectivity of the DA reactions.

关键词： Solvent effect Ionic liquids Diels-Alder reaction Reaction density functional theory

Dominant role of wettability in improving the specific capacitance

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Green Energy & Environment 2019年第2期4卷 171-179页

作者： Tongtong Liu Kai Wang Yongxiu Chen shuangliang zhao Yongsheng Han State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences School of Chemical Engineering University of Chinese Academy of Sciences State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and Technology

Here we report a strategy to enhance the energy density of supercapacitors by increasing the utilization rate of the specific surface area(SSA)via wettability improvement. The nonporous gold(NPG) film is used as the electrodes and the ionic liquid [EMIM]BF4 is the electrolyte. When the electrode is coated by paraffin, an increase of the contact angle leads to a remarkable reduction of the specific capacitance. While when acetonitrile is added into the electrolyte, the contact angle is decreased and the utilization rate of SSA is improved, which results in an increase of the specific capacitance. The addition of isopropyl acetate into the electrolyte leads to a further increase of the specific capacitance. To generalize the role of the wettability in improving the energy density, a carbon-based electrode is evaluated in the solution of potassium hydroxide. An addition of propyl alcohol into the potassium hydroxide solution leads to an increase of the specific capacitance, as well as a long-term stability of the supercapacitor. The role of conductivity in this study is excluded by designing experiments. This paper highlights the significance of wettability in determining the specific capacitance, showing an alternative to improve the energy density of supercapacitors.

关键词： Supercapacitor Energy density Specific capacitance Effective surface area Wettability

A reaction density functional theory study of solvent effects on keto-enol tautomerism and isomerization in pyruvic acid

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Chinese Journal of Chemical Engineering 2021年第3期34卷 10-16页

作者： Changjie Lu Weiqiang Tang Zijiang Dou Peng Xie Xiaofei Xu shuangliang zhao State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

It is important to study the solvent effect on keto-enol tautomerism that has applications in many areas of chemical *** this work,we use a multiscale reaction density functional theory(Rx DFT)to study the keto-enol tautomerism and isomerization of pyruvic *** results show that both effects of solvation and water assistance could reduce the reaction *** water molecule participates the reaction as a catalyst to accept/give the protons with forming a hexagonal ring in the transition *** a result of this temporary and intermediate hexagonal ring,the solute configuration undergoes a small variation during the reaction,giving a diminished contribution to the intrinsic reaction free *** solvent distribution shows a local ordering behavior near the solute that also reduces the contribution of solvation effect to the reaction *** assistance plays a major role in both pre-reaction and postreaction *** terms of the driving force for the reaction,the effects of both solvation and water assistance are important.

关键词： Solvent effect Reaction density functional theory Pyruvic acid Tautomerism Isomerization

Improved oxidation of hydrogen off-gas by hydrophobic surface modification: A multiscale density functional theory study

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Particuology 2019年第3期17卷 28-35页

作者： Cheng Lian Cheng Cai Xiangjian Shen shuangliang zhao Xinhai Yu Honglai Liu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and Technology Shanghai 200237 China School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 220237 China Research Center of Heterogeneous Catalysis and Engineering Science School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China Key Laboratory of Safety Science of Pressurized System (MOE) School of Mechanical Engineering East China University of Science and Technology Shanghai 200237 China

A catalytic micro-reactor for converting hydrogen off-gas into water was recently developed, through which the conversion efficiency of hydrogen gas was greatly improved by hydrophobic modification of the catalytic substrate. Herein, a hybrid theoretical method is reported that combines density functional theory (DFT) on both the quantum and molecular scales. This method allows the microscopic study of the mechanism by which the surface catalytic reaction can be manipulated. Specifically, quantum DFT calculations are performed to quantify the molecular interaction between the catalytic substrate and reagent or product. Classical DFT investigations are subsequently carried out to determine the local concentrations of reagents near catalytic sites subject to different surface coating conditions. Finally, the reaction efficiency is determined from the local concentrations based on collision theory. This multiscale method provides molecular insight for quantifying the effect of catalytic surface modification on the reaction efficiency. The method reveals that an optimal surface hydrophobic modification can promote the densities of reagents near the substrate, while depleting the produced water. These two factors promote the conversion efficiency. The exclusion of produced water from the catalytic substrate is affected more by the degree of polymer grafting than by the chain length of hydrophobic polymer moieties.

关键词： Surface reaction Hydrophobic modification Density functional theory Multiscale

Controlling solid form and crystal habit of triphenylmethanol by antisolvent crystallization in a microfluidic device

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Chinese Chemical Letters 2024年第4期35卷 393-398页

作者： Jun Lu Jinrui Yan Yaohao Guo Junjie Qiu shuangliang zhao Bo Bao East China University of Science and Technology Shanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Crystal habit and crystal form are critical elements in determining product properties and functions. In this work, we developed a microfluidic antisolvent crystallization technique to rapidly screen and accurately control the solid form and crystal habit of triphenylmethanol(Ph_(3)COH). This advanced technique separates the primary mixing of solutions from crystal formation(nucleation and growth) by introducing the microfluidic device, avoiding clogging in microchannels to obtain high-quality crystals. The results show that we can achieve controllable preparation of pure 2Ph_(3)COH·DMSO(DMSO solvate), pure Ph_(3)COH(form β), and mixed crystals with different mass ratios. Moreover, the microscale can prompt the DMSO solvate to grow into hexagonal sheet-like and bulk crystals. We can regulate the aspect ratio of hexagonal sheet-like crystals in binary solvents and control the crystal habit of the form β to transition between long needle-like shapes and short hexagonal prisms in DMF-H_(2)O. Meanwhile, we revealed that the solvent ratio, the antisolvent flow rate, and the initial concentration of Ph_(3)COH are the main factors affecting the solid form selectivity and morphology transition. Such a novel method would be considered as a promising technique to be extended to screen and control key crystallization parameters of other substances.

关键词： Microfluidics Triphenylmethanol Antisolvent crystallization Crystal habit Solid form

A reaction density functional theory study of solvent effect in the nucleophilic addition reactions in aqueous solution

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Green Energy & Environment 2022年第4期7卷 782-791页

作者： Cheng Cai Weiqiang Tang Chongzhi Qiao Bo Bao Peng Xie shuangliang zhao Honglai Liu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai200237China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical EngineeringGuangxi UniversityNanning530004China

Whereas the proper choice of reaction solvent constitutes the cornerstone of the green solvent concept,solvent effects on chemical reactions are not mechanistically well understood due to the lack of feasible molecular ***,by taking the case study of nucleophilic addition reaction in aqueous solution,we extend the proposed multiscale reaction density functional theory(RxDFT)method to investigate the intrinsic free energy profile and total free energy profile,and study the solvent effect on the activation and reaction free energy for the nucleophilic addition reactions of hydroxide anion with methanal and carbon dioxide in aqueous *** predictions of the free energy profile in aqueous solution for these two nucleophilic addition reactions from RxDFT have a satisfactory agreement with the results from the RISM and MD-FEP ***,the solvent effect is successfully addressed by examining the difference of the free energy profile between the gas phase and aqueous *** addition,we investigate the solvent effect on the reactions occurred near solid-liquid *** is shown that the activation free energy is significantly depressed when reaction takes place in the region within 10A distance to the substrate surface owing to the decrease of hydration free energy at the solid-liquid interface.

关键词： Reaction density functional theory Nucleophilic addition Solvent effect Charge models

Continuous synthesis of dolutegravir sodium crystals using liquid-gas heterogeneous microreactor

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Chinese Chemical Letters 2023年第3期34卷 302-307页

作者： Wei Luo Fen Liu Yaohao Guo Junjie Qiu Jinrui Yan shuangliang zhao Bo Bao State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

In this work, a liquid-gas heterogeneous microreactor was developed for investigating continuous crystallization of dolutegravir sodium(DTG), as well as revealing reaction kinetics and mixing mechanism with 3-min data acquisition. The reaction kinetics models were established by visually recording the concentration variation of reactants over time in the microchannel via adding pH-sensitive fluorescent dye. The mixing intensification mechanism of liquid-gas flow was quantified through the fluorescent signal to indicate mixing process, demonstrating an outstanding mixing performance with a mixing time less than 0.1 s. Compared with batch crystallization, continuous synthesis of dolutegravir sodium using liquid-gas heterogenous microreactor optimizes crystal distribution size, and successfully modifies the crystal morphology in needle-like habit instead of rod-like habit. The microreactor continuous crystallization can run for 5 h without crystal blockage and achieve D90 of DTG less than 30 μm. This work provides a feasible approach for continuously synthesizing dolutegravir sodium, and can optimize the existing pharmaceutical crystallization.

关键词： Microreactor continuous crystallization Dolutegravir sodium Reaction kinetics Mixing mechanism Crystal morphology Process operation

Effect of dimethyl carbonate on the behavior of water confined in carbon nanotube

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Chinese Journal of Chemical Engineering 2021年第3期34卷 177-185页

作者： Qingwei Gao Yumeng Zhang Aatto Laaksonen Yudan Zhu Xiaoyan Ji shuangliang zhao Yaojia Chen Xiaohua Lu College of Chemical Engineering State Key Laboratory of Materials-oriented Chemical EngineeringNanjing Tech UniversityNanjing 211816China Energy Engineering Division of Energy ScienceLuleåUniversity of Technology97187 LuleåSweden State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Department of Materials and Environmental Chemistry Arrhenius LaboratoryStockholm UniversitySE-10691 StockholmSweden Centre of Advanced Research in Bionanoconjugates and Biopolymers Petru Poni Institute of Macromolecular ChemistryAleea Grigore Ghica-Voda41A700487 IasiRomania Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

The dehydration of water by dimethyl carbonate(DMC)is of great significance for its application in electrochemistry and oil *** the rapid development of nanomaterial,one-dimensional(*** nanotube(CNT))and two-dimensional(*** graphene)materials have been widely used for molecular *** this work,the molecular behavior of dimethyl carbonate/water mixture confined in CNT with varying diameters was studied based on molecular dynamics *** to different van der Waals interactions for the components in the mixtures with the solid surface,DMC molecules are preferentially adsorbed on the inner surface of the pore wall and formed an adsorption *** with the pure water molecules confined in CNT,the adsorption DMC layer shows notable effect on the local compositions and microstructures of water molecules under nanoconfinement,which may result in different water *** analysis shows that the surface-induced DMC molecules can destroy the hydrogen bonding network of water molecules and result in an uniform and dispersed distribution of water molecules in the *** clear molecular understandings can be useful in material design for membrane separation.

关键词： Dimethyl carbonate Carbon nanotube Solid/fluid interface Adsorbed layer Molecular simulation

Efficient solar cells based on cosensitizing porphyrin dyes containing a wrapped donor, a wrapped π-framework and a substituted benzothiadiazole unit

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Science China Chemistry 2019年第8期62卷 994-1000页

作者： Yunyue Lu Yingchun Cheng Chengjie Li Jiaxin Luo Weiqiang Tang shuangliang zhao Qingyun Liu Yongshu Xie Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering and State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237China College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266510China

Three new porphyrin dyes XW45-XW47 have been synthesized employing a dialkoxy-wrapped phenothiazine donor, a tetraalkoxy-wrapped porphyrin π-framework, a benzothiadiazole(BTD)-based auxiliary acceptor, and an anchoring benzoic acid group. On the basis of our previously reported dye XW36, XW45 was synthesized by introducing a BTD unit to broaden the absorption spectrum, further introducing a hexyl-substituent into the BTD unit afforded XW46, and an additional fluorine atom was introduced to the carboxyphenyl acceptor to afford XW47. As expected, the BTD unit obviously broadens and red-shifts the absorption threshold of XW45-XW47 to ca.750 nm. Dye-sensitized solar cells(DSSCs) were fabricated based on a cobalt electrolyte using chenodeoxycholic acid(CDCA) as the coadsorbent. Under full sun illumination, XW45 exhibits an efficiency of 9.73%, which is slightly lower than that of 10.19% obtained for the reference dye SM315. By contrast, XW46 and XW47 show higher efficiencies than SM315 owing to the improved anti-aggregation ability associated with the hexyl group on the BTD unit and better ICT effect induced by the fluorine atom on the carboxyphenyl unit. Thus, XW47 exhibits the highest efficiency of 10.41% among the porphyrin dyes. Furthermore, PT-C6 was used as the cosensitizer to improve the light harvesting ability and efficiencies of the cells due to its broad absorption within 350–560 nm. Thus, high efficiencies of 10.32%, 11.38% and 10.90% were achieved for the cosensitized solar cells based on XW45–XW47, respectively, owing to the obviously enhanced photocurrent density(JSC). In addition, under 30% full sun illumination, XW46+PT-C6 exhibits a high efficiency of 13.08%. These results give an effective method for building high performance DSSCs through the cosensitization of porphyrin dyes containing a wrapped donor, a wrapped porphyrin framework and a properly substituted auxiliary benzothiadiazole unit.

关键词： dye-sensitized solar cells porphyrin dyes benzothiadiazole cosensitization