In situ FTIR Spectroscopic Studies of (Bi)sulfate Adsorption and Electrocatalytic Reaction of Aspartic Acid on Nanostructured Metal Electrodes

本论文运用电化学循环伏安法(CV)和原位红外反射光谱(insituFTIRS)系统地研究了硫酸阴离子在各种反射率基底上的Pt纳米粒子电极(nm-Pt/S(n)，S=GC，Pt，Au)表面的吸附，以及不同pH值溶液中门冬氨酸(Asp)在本体Au和纳米Au电极表面的电催化过程，主要结果如下： 1、硫酸阴离子在纳米Pt电极上的吸附。首次发现所制备的纳米Pt电极对硫酸阴离子的吸附表现出异常红外效应(AIREs)，即吸附态的硫酸阴离子在nm-Pt/S(n)电极上给出谱峰方向倒反、谱峰强度增强的红外光谱特征。该研究不仅首次将AIREs现象由强吸附物种(如CO、CN-和SCN-等)拓展到弱吸附物种(硫酸阴...Cyclic voltammetry (CV) and in situ FTIR spectroscopy (in situ FTIRS) were applied to the study of the adsorption of (bi)sulfate on Pt nanoparticles substrated on materials with different IR reflectivity (nm-Pt/S(n), S = GC, Pt, Au) and electrocatalytic reaction of aspartic acid (Asp) on bulk and nanostructured Au electrodes. The main results are summarized below. 1. Study of the adsorption of (b...学位：理学博士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：B20032502

从政治参与的角度考察我国坚持陪审制度的现实性

陪审制度的本质是一种重要的民主政治的政治思想和司法功能的体现,陪审制度的确立和完善,是人类走向民主文明的司法形式之一。本文认为重新认识陪审制度的价值双重性,彰显陪审制度的政治价值与司法价值,在推进公众政治参与需求下,完善我国的人民陪审制,已然成为法学理论界及司法实务界应重新认识的重要课题

Ⅰ级粉煤灰对水泥净浆开裂的影响

采用环约束法,试验研究了Ⅰ级粉煤灰对不同水胶比下水泥净浆开裂的影响。试验研究发现:Ⅰ级粉煤灰在低水胶比(0.24)情况下对净浆开裂几乎没有影响,当水胶比为0.32和0.40时抗裂作用明显;较高水胶比(0.32、0.40)情况下,Ⅰ级粉煤灰对净浆的抗裂性能有较好的改善作用,在20%～65%掺量范围内,随着掺量的增大,净浆的开裂龄期延长,抗裂性能提高

Electrochemical behavior of p-dihydroxybenzene in DMPC biomimetic membrane

在金电极上构筑一种双肉豆蔻磷脂酰胆碱(DMPC)仿生浇铸膜。经椭圆偏振仪和电化学方法测量证实, DMPC仿生膜是较为致密的多层膜,同时对苯二酚能够透过DMPC仿生膜到达金电极表面进行氧化反应。结果表明,对苯二酚不仅可在脂质膜中进行电子转移,而且是一种重要的生物分子。反应在仿生环境内进行,也为研究生物小分子在真正的生物体内的反应提供有益的帮助。本文探讨对苯二酚在仿生膜修饰电极上的电化学行为,为生物膜中的电子转移过程提供了十分重要的信息。The casting method to form dimyristoyl phosphatidyl choline(DMPC)mimetic biomembrane on an Au electrode is proposed.The results of ellipsometer and electrochemical methods confirmed that the film is a compact membrane that can block the electron transferring process,p-Dihydroxybenzene can reach the electrode surface and occur redox reactions by passing through transient defects in individual bilayers.Such defects occur in biomembranes and are accentuated by relatively small electric fields.The electrochemical behavior of p-dihydroxybenzene in this membrane was also investigated,p-Dihydroxybenzene is biologically important molecule because of its function of transferring electrons in lipid layers.This reaction occur in the bionic environment,which provide the useful help to study the real reaction of small molecules in the biological organisms.Studies on the electrochemical behavior of p-dihydroxybenzene in the DMPC biomimetic membrane provide useful information for elucidating biological electron transfer processes concerning lipid layers.国家自然科学基金项目(20833005,20873116)。~

纤维蛋白原在Pt电极上的界面电化学研究

应用电化学方法和电化学原位红外反射光谱(electrochemical in-situ FTIR)等研究了纤维蛋白原在Pt电极上的界面电化学行为.结果表明:纤维蛋白原在Pt电极上的吸附使电极的析氢与氧脱附过程减弱,影响程度随扫速的增加而增强;同样纤维蛋白原的吸附会降低亚铁氰化钾-铁氰化钾电对的氧化还原反应可逆性和电流;在-0.1~0.6V(vs.SCE)扫描范围内没有出现纤维蛋白原的特征"氧化还原"峰.电化学原位红外反射光谱测试表明纤维蛋白原在0.3~0.5V(vs.SCE)间发生化学反应,有新的产物生成

Ion-Conducting Mechanism of Composite Polymer Electrolyte:An Emission FTIR Spectroscopy Study

运用发射FTIR光谱技术,实时监测SBA-15掺杂制备的复合聚合物电解质随温度升高其结晶状态变化的规律,结合电化学和SEM研究结果分析了无机填料对离子电导率的影响,并初步提出离子导电增强的机制。文章将为发射FTIR光谱技术应用于锂电池研究进行了探索。Solvent-free, composite electrolytes based on poly(ethylene oxide) (PEO) were prepared by using mesoporous silica SBA-15 with surface modification of (trimethylchlorosilane) as the filler. The samples were explored by emission FTIR spectroscopy at elevated temperatures. The results of emission FTIR spectra illustrated the dependence of crystalline PEO phase on temperature. On the basis of electrochemistry, SEM, and emission FTIR studies, the effect of inorganic filler on the ionic conductivity was analyzed, and a conclusion concerning the ion-conducting mechanism of composite polymer electrolyte was drawn. The exploratory experiments demonstrated that the emission FTIR spectroscopy is an important method to be applied in the study of lithium batteries.国家“973”项目(2002CB211804);; 国家自然科学基金项目(20433040,20573085,20673091)资

FTIR Spectroscopic Studies of PEO-based Polymer Electrolyte with Ionic Liquid

以聚氧化乙烯(PEO)为聚合物基体,双三氟甲基磺酸亚酰胺锂(l ITfSI)为锂盐,加入不同量的离子液体(bM IMPf6)为增塑剂,制备离子液体聚合物电解质.运用发射fTIr光谱技术实时监测所制备聚合物电解质的结构随温度的变化.结合fTIr透射光谱、SEM和Xrd的研究结果分析了离子液体对离子电导率的影响,并初步提出离子导电增强机制.Polymer electrolytes based on poly(ethylene oxide)(PEO) was prepared using LiTFSI as lithium salt and doping with 1-butyl-3-methylimidazolium hexaflurophosphate(BMIMPF6) by solution casting method.The addition of BMIMPF6 resulted in an increase of the ionic conductivity.When the amount of the ionic liquid is 40%,the ionic conductivity could reach 1.80×10-4 S/cm at 40 ℃.The samples were explored by emission FTIR spectroscopy at elevated temperatures,which illustrated the dependence of crystalline PEO phase on temperature.Based on results of SEM,XRD,transmission FTIR and emission FTIR,the effect of ionic liquid on the ionic conductivity was analyzed.It was revealed that the ionic liquid decreased cystallinity of the polymer,and resulted in the increase of ionic conductivity.The study has demonstrated that the FTIR spectroscopy is an important method for investigations of lithium batteries.国家“九七三”计划(批准号:2002CB211804);国家自然科学基金(批准号:20433040;20573085)资

Adsorption and Oxidation of L-Lysine on Nanometer Scale Au Film Electrodes in Alkaline Solution

采用原位红外反射光谱(in situFTIRS)和循环伏安法(CV)研究了碱性介质中L-赖氨酸在纳米金膜电极(nm-Au/GC)上的解离吸附和氧化过程.研究结果表明,在碱性溶液中以阴离子形式存在的赖氨酸[-OOC—CH—NH2—(CH2)4—NH2]在低电位区间(-0.95~-0.80 V,vs.SCE)发生部分解离,生成AuCN-物种(约2110 cm-1),同时赖氨酸阴离子的羧基侧还可通过两个氧原子与金电极表面相互作用.随着电位的升高,吸附态CN-氧化产生NCO-,OCN-和AuCN,其对应的红外吸收峰分别位于2254,2168和2226 cm-1附近.Amino acids are the building blocks of peptides and proteins.An amino acid molecule contains multi-functional groups such as —COOH,—NH2,—OH and —CHx,which leads to the amino acids to be used often as model reagents in surface electrochemistry and electrocatalysis,for the purpose of obtaining information about the interaction of different functional groups with electrocatalyst surfaces and the role of these functional groups in electrocatalysis of small organic fuels.Up to now,the reaction mechanism of amino acid electrooxidation is still far to be well understood.In this study,adsorption and oxidation of L-lysine on electrodes of nanometer scale thin film of gold in alkaline solutions were investigated using in situ FTIR reflection spectroscopy and electrochemical methods.The FTIRS result demonstrate that the dissociative adsorption of lysine on Au surface can occur in a low potential region,and the chemisorbed species were identified as adsorbed CN-species(cyanide,2110 cm-1).Another reversibly(or loosely) adsorbed species may be the deprotonated amino acids,which were bound to the surface by both oxygen atoms of carboxyl group.When electrode potential is higher than 0.1 V,the adsorbed CN-can be oxidized to NCO-(2254 cm-1);when electrode potential is above 0.3 V,OCN-(cyanate,2168 cm-1) appeared as oxidative species;and when the potential is increased further up to 0.5 V,another further oxidative species,the AuCN species(gold cyanide,2226 cm-1) appeared.This study is of importance in understanding the interaction between amino acids and Au film electrodes.国家自然科学基金(批准号:20673091,20423002)资

in situ FTIR Spectroscopic Studies of Adsorption and Oxidation of L-Serine on Pt Electrodes in Neutral Solutions

运用电化学循环伏安(CV)和原位红外反射光谱(In SITufTIrS)研究了中性介质中l-丝氨酸在PT电极上的解离吸附和氧化过程.结果表明,在中性溶液中,以两性离子形式存在的丝氨酸可以在很低的电位下(-0.6 V,VS.SCE)在PT电极表面发生解离吸附,生成强吸物种一氧化碳(COl)、(COb)和氰负离子(Cn-).研究结果还表明,当电位低于0.7 V(VS.SCE)时,Cn-能稳定存在于电极表面,抑制丝氨酸的进一步反应.在更高电位时则主要为丝氨酸分子的氧化过程.The dissociative adsorption and oxidation of L-serine on platinum electrode in neutral solutions were studied via in situ FTIR reflection spectroscopy and electrochemical methods.The FTIRS results demonstrate that the serine can be easily dissociated on Pt surface at potentials below-0.6 V(vs.SCE) to form cyanide(--2100 cm-1) and carbon monoxide(COL,--2034 cm-1;COB,--1870 cm-1).The observation of an absorption band at 2343 cm-1 is ascribed to CO2,which implies the cleavage of the C—C bond during the dissociative adsorption of serine.It has determined that the cyanide was strongly adsorbed on electrode surface in a wide potential region below 0.7 V(vs.SCE) and inhibited the oxidation of serine.At higher potentials,the serine molecules could be oxidized directly to yield the main product CO2 species.As the pH decreased in the spectroelectrochemical cell during serine reactions,the acidic serine species also detected.The present study revealed the interaction of serine with Pt electrode surface,and suggested a possible reaction mechanism of serine on Pt electrode surface in neutral solutions.国家自然科学基金(批准号:20673091;20833005)资

Cyclic Voltammetric and in-situ FTIR Spectroscopic Studies of Adsorption and Reduction of NO on Electrode of Pt Nanoparticles

运用电化学循环伏安法(CV)和原位傅里叶变换红外反射光谱(in situ FTIRS)研究了酸性介质中铂纳米粒子电极(nm-Pt/GC)上NO吸附及其电催化还原过程.结果表明,NO分子的吸附是电催化还原的重要步骤.在铂纳米粒子电极上饱和吸附的NO存在两种不同键合强度的吸附态,其中弱吸附的NO(NOW)在0.60 V至-0.05 V电位区间还原生成N2O和NH4+;而强吸附的NO(NOS)则在-0.05 V至-0.15 V区间还原,其产物为NH+.Adsorption and reduction of NO on electrode of Pt nanoparticles in acid solutions were studied by means of cyclic voltammetry(CV) and in-situ FTIR spectroscopy.The results indicated that the reduction of NO is a complicated process including the adsorption of NO on electrode surface.Two types of surface-bonded NO were determined on Pt nanoparticles.The weakly adsorbed NO was reduced between 0.6 V and-0.05 V,which yielded nitrous oxide(N2O) and ammonium(NH+4) as products;while the strongly bonded NO was reduced at more negative potentials between-0.05V and-0.15V,producing only NH4+ species.作者联系地址：厦门大学固体表面物理化学国家重点实验室化学化工学院化学系;Author's Address: State Key Laboratory of Physical Chemistry of Solid Surfaces,Department of Chemistry,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,Fujian,Chin