Electrochemically shape-controlled synthesis of Fe nanoparticles, their structural characterization and properties

摘要 一般来说，金属纳米催化剂的催化活性可以通过以下两个途径来提高：其一，改变金属纳米催化剂的成分，也就是通过改变化学组成和电子结构。其二，改变金属纳米粒子催化剂表面的原子排列结构，即通过调谐表面几何结构，后者可以通过形貌控制合成来实现。这也是当前纳米科技技术的一个重要的前沿研究领域。 电催化和多相催化反应都是表面反应，催化剂作用的关键是其表面原子与反应分子之间的相互作用。因此，若能通过形貌控制合成，制备出具有开放的表面原子排列结构的金属催化剂，将可以显著提高催化剂的活性和选择性。这将对催化剂的制备产生重要而深远的影响。 电化学方法具有独到的优势，被证明是一种实现纳米粒子形状控制合成...Abstract Catalytic performance of nanocrystals (NCs) can be finely tuned either by changing their composition, which mediates electronic structure, or by altering their shape, which determines their surface atomic arrangement and coordination. Therefore, the shape-controlled synthesis of nanocrystals presents an important way for tuning the activity, stability, and selectivity of nanocrystal ca...学位：理学硕士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：1912005130187

Electrochemical and In situ FTIR Studies of Maleic Acid Reduction in BF_4

作者自行合成了离子液体[BMIM]BF4,用循环伏安法(CV)、计时电量法(CA)和电化学原位红外反射光谱(in situFTIR),从分子水平考察了离子液体中马来酸在玻碳(GC)电极上的电化学还原过程。结果表明,[BMIM]BF4中马来酸在GC电极上的还原为不可逆过程,测得扩散系数D=9.62×10-8cm2/s;in situFTIRS研究发现,马来酸在离子液体[BMIM]BF4和水溶液中的电还原生成丁二酸的机理不同。在[BMIM]BF4中马来酸还原发生在其中的一个羧基上,即马来酸首先获得一个电子生成阴离子自由基,随后可能获得一个电子生成二价阴离子,或者获得一个电子并在2个H+的作用下生成醛类物质和水。The ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborates(BF4) was synthesized and used as both solvent and electrolyte.Electrochemical reduction of maleic acid in the ionic liquid was studied by cyclic voltammetry(CV),chronoamperometry(CA) and in situ FTIR spectroscopy.The results demonstrated that the reduction of maleic acid on GC electrode is an irreversible process controlled by diffusion.The diffusion coefficient D of maleic acid is determined to be 9.62×10-8 cm2/s.in situ FTIR results illustrated that the reduction of maleic acid in ionic liquids occurs on the carboxyl.The first step is to geaerte radical anions,which are reduced then to aldehyde species and water with two hydrogen ions.国家自然科学基金(批准号:20673091,20833005)~

Preparation of CoPt Nanoparticles Films and Thire Electrocatalytic Properties

通讯联系人：孙世刚 E-mail:[email protected]本工作为国家自然科学基金(批准号：20673091)和国家重点基础研究发展规划(批准号：2002CB21 1804)资助项

Investigation of Porous Silicon/Carbon Composite as Anodes for Lithium Ion Batteries

以商业化多晶硅粉为原料,采用金属银催化剂诱导化学腐蚀的方法制得三维多孔硅材料。通过优化腐蚀条件,得到孔径约为130 nM,比表面为4.85 M2/g的多孔硅材料。将多孔硅和PAn溶液混合球磨并经高温烧结后在多孔硅表面包覆上一层致密的无定形碳膜,从而制得多孔硅/碳复合材料作为锂离子电池的负极材料。3d多孔硅结构可以缓解电化学嵌/脱锂过程中材料的体积效应,无定形碳膜层可有效改善复合材料的导电性能。电化学性能测试表明,该多孔硅/碳复合负极材料电池在0.4 A/g的恒电流下,首次放电容量3345 M AH/g,首次循环库伦效率85.8%,循环55次后容量仍保持有1645 M AH/g。并且在4 A/g的倍率下,容量仍维持有1174 M AH/g。该方法原料成本低廉,可规模化生产。3D porous silicon was synthesized by metal-assisted chemical etching process using commercially available polycrystalline silicon powders.After chemical etching in optimized solution, 3D porous silicon structures with pore size of about 130 nm and specific surface area of about 4.85 m2/g was obtained.Subsequently, the 3D porous silicon powders treated with ball milling and heat carbonization processes were coated with amorphous carbon and utilized as the anode electrode material for lithium ion battery.The combination of the 3D porous structure and a carbon coating layer can accommodate large mechanical strains by providing the empty space of the pores to alleviate the volume change, and by increasing the electrical conductivity with the carbon layer.The electrodes achieve an initial charge capacity of 3345 m Ah/g with coulombic efficiency of 85.8% as well as a high reversible capacity of 1645 m Ah/g after 55 cycles at 0.4 A/g.And it is capable to retain a capacity of 1174 m Ah/g even at 4 A/g.Thus, this work introduces a novel and easy potential industrial method for fabrication Si/C materials for high-performance lithium ion battery.国家自然科学基金(61176050;21233004)~

油酰乙醇胺对高脂血症大鼠降血脂及肝脏的保护作用

目的观察油酰乙醇胺(OEA)对高脂血症模型大鼠降血脂及肝脏保护作用。方法高脂饮食建立高脂血症大鼠模型,分别观察OEA(10,203,0 mg/kg)对高脂血症大鼠的血清胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、谷丙转氨酶(ALT)、肝重和肝脏系数、肝脏丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)的影响。制作冰冻切片观察大鼠肝脏脂质变性程度。结果与模型组相比,OEA(20,30mg/kg)具有降血脂作用,同时降低血清ALT、肝脏脂质、肝重和肝脏系数、肝脏MDA水平,升高肝脏GSH-Px活力。结论 OEA能降低高脂血症大鼠血脂、抑制肝脏脂肪沉积,并减轻脂质过氧化物对肝脏的损伤

Electrochemical and in situ FTIRS of maleic acid reduction in[BMIM]BF_4 on Pt electrode

采用循环伏安法(CV)、计时电量法(CA)和电化学原位红外反射光谱(in situ FTIRS),从分子水平上研究了离子液体[BMIM]BF_4中马来酸在Pt电极上的电化学还原过程。结果表明,[BMIM]BF_4中马来酸在Pt电极上的还原是受扩散控制的准可逆过程,测得扩散系数为1.0×10~(-7)cm~2·s~(-1);in situ FTIRS研究发现, [BMIM]BF_4中马来酸在Pt电极上的还原发生在其中的一个羧基位上,即马来酸首先获得一个电子生成阴离子自由基,随后再获得一个电子生成二价阴离子。Electrochemical reduction of maleic acid in the ionic liquid was studied by cyclic voltammetry (CV),chronoamperometry(CA)and in situ FTIR spectroscopy.The results demonstrated that the reduction of maleic acid on Pt electrode is a quasireversible process controlled by diffusion.The diffusion coefficient of maleic acid is determined to be 1.0×10~(-7)cm~2·s~(-1).In situ FTIRS results illustrated that the reduction of maleic acid in ionic liquids occurs on the carboxyl.The first step is to generate radical anions, which are reduced to aldehyde species.国家自然科学基金项目(20833005,20873113)。~

Electrochemical Preparation of Fe Core /Pt Shell Nanoparticle Modified Glassy Carbon Electrode and Their Electrocatalytic Activities for Nitrite Reduction

通讯联系人: 陈声培，男，教授; E-mail: shpchen@ xmu． edu． cn; 研究方向:电化学催化、有机电合成、谱学电化学、表面电化学等[中文文摘]通过循环伏安法(CV)在玻碳(GC)电极表面电沉积出分布较为均匀的纳米Fe粒子，制得纳米Fe粒 子修饰的GC(纳米Fe /GC)电极，再经“电荷置换”制得具有Fe核Pt壳结构的纳米粒子修饰的(纳米PtFe / GC) 电极。SEM 结果显示，纳米Fe/GC和纳米PtFe/GC 表面粒子的形貌均呈立方体形，分布较为均匀，粒径在 60 nm 左右。纳米PtFe /GC 电极对亚硝酸盐的还原具有很高的电催化活性。3 种电极的电催化活性顺序依次 为: 纳米Fe /GC ＜ 纳米Pt /GC ＜ 纳米PtFe /GC。相对于纳米Pt /GC 电极，纳米PtFe /GC 电极的起始还原电位 (Ei)正移了0.14V，还原峰电流(ip)增大了3倍。 [英文文摘]Iron nanoparticles were uniformly deposited on glassy carbon electrode by electrochemical cyclic voltammetry，and Fe core/Pt shell nanoparticles ( nano-PtFe) were further obtained through “galvanic replacement”．SEM observation illustrated that cuboid nanoparticles with average sizes，ca． 60 nm，dispersing uniformly on GC electrode surfaces． The electrocatalytical activities for nitrite reduction by nano-Fe /GC， nano-Pt /GC and nano-PtFe /GC electrodes were studied by cyclic voltammetry( CV)． The catalytic activity is in the order of: nano-Fe /GC ＜ nano-Pt /GC ＜ nano-PtFe /GC． The onset potential( Ei ) of nitrite reduction on nano-PtFe /GC electrode is positively shifted 0. 14 V，and the steady reduction current density(ip) is about 3 times of that from nano-Pt /GC electrode．国家自然科学基金(20833005，20873113)、浙江省重中之重学科开放基金(20090503)资助项

聚松香乙二醇酯丙烯酯及其氧化物的合成研究

松香的主要成分是各种树脂酸(C19H29COOH),其中酸性物质占90%左右,它是一个三环菲骨架,大都含有两个双键的一元羧酸。本文以三氯化铁为催化剂,松香、乙二醇为原料,合成松香乙二醇酯,再与丙烯酸反应,得到松香乙二醇酯丙烯酯;而后在催化剂的作用下催化聚合得到聚松香乙二醇酯丙烯酯,再在催化剂作用下用过氧化氢氧化聚松香乙二醇酯丙烯酯,本文中测定了聚松香乙二醇酯丙烯酯和聚松香乙二醇酯丙烯酯氧