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MP2 Study on the Proton Transfer Mechanism of Glycine Assisted by Water

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Chinese Journal of Structural Chemistry 2009年第7期28卷 903-909页

作者：孟祥军 Chemistry Department of Tangshan Normal College

The geometries of glycine-nH2O （n = 1-5） complexes and the transition states of proton transfer in glycine-H2O system were calculated at the MP2/6-31＋＋G＊＊//MP2/6-31G＊ level, upon which we discovered the proton transfer mechanisms, including the number of water molecules necessary for the stabilization of zwitterions and the effect of increasing water molecules on the proton transfer. To our interest, we found that only one water molecule can stabilize the zwitterions; in addition, with the increment of water molecules, the activation energy of positive reaction decreases and that of reverse reaction increases gradually. Glycine will be ionized completely while the water molecules reach to a certain number.

关键词： MP2 glycine zwitterions proton transfer ionization

High-Performance Perovskite Solar Cells with Zwitterion-Capped-ZnO Quantum Dots as Electron Transport Layer and NH_(4)X(X=F,Cl,Br)Assisted Interfacial Engineering

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Energy & Environmental Materials 2024年第5期7卷 321-331页

作者： Rashmi Runjhun Essa A.Alharbi Zygmunt Druzyński Anurag Krishna Ma■gorzata Wolska-Pietkiewicz ViktorŠkorjanc Thomas P.Baumeler George Kakavelakis Felix Eickemeyer Mounir Mensi Shaik M.Zakeeruddin Michael Graetzel Janusz Lewiński Institute of Physical Chemistry Polish Academy of Sciences Kasprzaka 44/5201-224 WarsawPoland Laboratory of Photonics and Interfaces Institute of Chemical Sciences and EngineeringSchool of Basic SciencesEcole Polytechnique Fédérale de LausanneCH-1015 LausanneSwitzerland Microelectronics and Semiconductors Institute King Abdulaziz City for Science and Technology(KACST)11442 RiyadhSaudi Arabia Faculty of Chemistry Warsaw University of TechnologyNoakowskiego 300-664 WarsawPoland Institute of Chemical Sciences and Engineering École Polytechnique Fédérale de LausanneValais WallisCH-1951 SionSwitzerland

The systematic advances in the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs)have been driven by the developments of perovskite materials,electron transport layer(ETL)materials,and interfacial passivation between the relevant *** zinc oxide(ZnO)is a promising ETL in thin film photovoltaics,it is still highly desirable to develop novel synthetic methods that allow both fine-tuning the versatility of ZnO nanomaterials and improving the ZnO/perovskite *** various inorganic and organic additives,zwitterions have been effectively utilized to passivate the perovskite *** this vein,we develop novel,well-characterized betaine-coated ZnO QDs and use them as an ETL in the planar n-i-p PSC architecture,combining the ZnO QDs-based ETL with the ZnO/perovskite interface passivation by a series of ammonium halides(NH_(4)X,where X=F,Cl,Br).The champion device with the NH4F passivation achieves one of the highest performances reported for ZnO-based PSCs,exhibiting a maximum PCE of~22%with a high fill factor of 80.3%and competitive stability,retaining~78%of its initial PCE under 1 Sun illumination with maximum power tracking for 250 h.

关键词： interface passivations perovskites quantum dots solar cells zinc oxide zwitterions

Zwitterion-assisted transition metal dichalcogenide nanosheets for scalable and biocompatible inkjet printing

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Nano Research 2020年第10期13卷 2726-2734页

作者： Hyeokjung Lee Min Koo Chanho Park Madhumita Patel Hyowon Han Tae Hyun Park Pawan Kumar Won-Gun Koh Cheolmin Park Department of Materials Science and Engineering Yonsei University Seoul 03722Republic of Korea Department of Chemical and Biomolecular Engineering Yonsei UniversitySeoul 03722Republic of Korea

Inkjet printing of two-dimensional(2D)transition metal dichalcogenide(TMD)nanosheets fabricated by liquid-phase exfoliation(LPE)allows simple,mass-producible,and low-cost photo-electronic *** LPE processes involve toxic and environmentally hazardous solvents;however,dispersants have restricted the extent of applications of 2D-TMD ***,various 2D-TMD nanosheets,including MoS2,MoSe2,WS2,and WSe2,in addition to few-layered graphene,are inkjet-printed using a LPE process based on zwitterionic dispersants in *** with cationic and anionic species are water-soluble,while alkyl chain moieties associated with two ionic species adhere universally on the surface of TMD nanosheets,resulting in high throughput liquid exfoliation of the *** zwitterion-assisted TMD nanosheets in water are successtully employed as an ink without the need for additives to adjust the viscosity and surface tension of the ink for use in an office inkjet printer;this gives rise to A4 scale,large-area inkjet-printed images on diverse substrates,such as metals,oxides,and polymer substrates patchable onto human *** with conductive graphene nanosheet inks allowed the development of mechanically flexible,biocompatible-printed arrays of photodetectors with pixelated MoSe2 channels on a paper exhibiting a photocurrent ON/OFF ratio of approximately 1038 and photocurrent switching of 500 ms.

关键词： transition metal dichalcogenide nanosheets zwitterions zwitterion-assisted liquid-phase exfoliation scalable inkjet printing biocompatible

A Direct Route to Tetrahydropyridazine Derivatives via DMAP-Catalyzed [4+2] Annulation of Allenoates with Arylazosulfones

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Chinese Journal of Chemistry 2023年第22期41卷 3031-3036,I0002页

作者： Xin Ji Ziyang Li Jinfeng Zhang Yicheng Zhang Ling-Guo Meng Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of EducationSchool of Chemistry and Materials ScienceHuaibei Normal UniversityHuaibeiAnhui 235000China

Herein,a DMAP-catalyzed[4+2]annulation ofα-substituted allenoates with arylazosulfones is reported,which affords facile access to tetrahydropyridazine derivative in synthetically useful *** reaction features mild conditions and good functional group ***,the resultant products can be readily transformed into pyridazin-3-one derivatives in the presence of DDQ.

关键词： DMAP [4+2]Cycloaddition Tetrahydropyridazihe derivatives Pyridazin-3-one derivatives Allenes zwitterions N-Heterocycles

Thermodynamic solvation of a series of homologous α-amino acids in non-aqueous mixture of ethylene-glycol and N,N-dimethyl formamide

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Journal of Biophysical Chemistry 2011年第3期2卷 185-193页

作者： Kalachand Mahali Sanjay Roy Bijoy Krishna Dolui Dept. of Chemistry Shibpur Dinabundhoo Institution(College) Howrah India

Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic ethylene glycol (EG) to dipolar aprotic N,N-dimethyl formamide (DMF) have been evaluated from solubility measure-ments at five equidistant temperatures i.e from 15 to 350C. The observed ΔG0t(i) and TΔS0t(i) Vs composition profiles are complicated because of the various interaction effects. The chemical effects of the transfer Gibbs energies (Δ***(i)) and entropies of transfer (Δ***(i)) have been obtained after elimination of cavity effect, estimated by the scaled particle theory and dipole-dipole interaction effects, estimated by the use of Keesom-orientation expression. The chemical contributions of transfer energetics of homologous α-amino acids are guided by the composite effects of increased dispersion interaction, basicity and decreased acidity, hydrogen bonding effects and solvophobic solvation of ethylene glycol and N, N-dimethyl formamide mixed solvent as compared to that of reference solvent (ethylene glycol).

关键词： Non-Aqueous Solvent System Transfer Energetic zwitterions α-Amino Acids Solvophobic Solvation