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31.
《Electroanalysis》2005,17(2):186-190
We report for the first time on the electroassisted biomimetic activation of molecular oxygen by a newly prepared electropolymerized polypyrrole‐manganese phthalocyanine film. The prepared films and their intervention in the electroassisted catalytic reduction of molecular oxygen were analyzed by cyclic voltammetry and UV‐visible spectrophotometry on optically transparent electrodes. The obtained results demonstrate the probable existence of the key‐steps responsible for the suggested formation of the highly reactive manganese oxo intermediate. 相似文献
32.
《Electroanalysis》2003,15(9):779-785
We have investigated the electrocatalytic activity of cobalt tetra‐aminophthalocyanine (CoTAPc) for the one‐electron oxidation of thiols of various sizes, namely 2‐mercaptoethanol, 2‐mercaptoethanesulfonic acid, reduced glutathione and L ‐cysteine, using adsorbed monomeric CoTAPc and electropolymerized poly‐CoTAPc films of different thickness on a vitreous carbon electrode. Our results show that the electrocatalytic activity of poly‐CoTAPc films towards the oxidation of the thiols increases slightly with the thickness of the film, but remains similar to that of the adsorbed monomeric CoTAPc. The higher stability of the electropolymerized poly‐CoTAPc films makes them attractive for applications in the activation and/or the detection of thiols. We have assessed this approach by designing ultra‐micro‐carbon‐fiber electrodes, coated with poly‐CoTAPc, and combining their use with different electrochemical techniques (cyclic voltammetry, differential pulse voltammetry and differential normal pulse amperometry) for the electroanalysis of the examined thiols. 相似文献
33.
34.
用循环伏安与现场可见紫外光谱电化学方法研究了氯化4-特丁基苯氧基铁酞菁[(TbPc)Fe(Ⅲ)Cl]电化学行为.结果表明,在四氢呋喃溶剂中其正电位区经历了两步氧化过程,对应于Fe(Ⅲ)/Fe(Ⅳ)以及Fe(Ⅳ)/阳离子自由基的生成反应,负电位区还原过程经历了Fe(Ⅲ)/Fe(Ⅱ),Fe(Ⅱ)/Fe(Ⅰ)和Fe(Ⅰ)/阴离子自由基生成的3个步骤,阐述了配位效应对氧化还原机理的影响.指出Fe(Ⅳ)不寻常价态的出现,是阴离子Cl-的轴向配位对超常价态起到稳定作用的结果. 相似文献
35.
Electrocatalytic oxidation and detection of hydrazine in pH 7.0 conditions were studied by using gold electrode modified with self-assembled monolayer (SAM) films of iron phthalocyanine (FePc) complex axially ligated to a preformed 4-mercaptopyridine SAMs. The anodic oxidation of hydrazine in neutral pH conditions with FePc-linked-mercaptopyridine-SAM-modified gold electrode occurred at low overpotential (0.35 V versus Ag|AgCl) and the treatment of the voltammetric data showed that it was a pure diffusion-controlled reaction with the involvement of one electron in the rate-determining step. The mechanism for the interaction of hydrazine with the FePc-SAM is proposed to involve the Fe(III)Pc/Fe(II)Pc redox process. Using cyclic voltammetry (CV) and Osteryoung square wave voltammetry (OSWV), hydrazine was detected over a linear concentration range of 1.3 × 10−5 to 9.2 × 10−5 mol/L with low limits of detection (ca. 5 and 11 μM for OSWV and CV, respectively). At concentrations higher than 1.2 × 10−4 mol/L the anodic peak potential shifted to 0.40 V (versus Ag|AgCl), and this was interpreted to be due to kinetic limitations resulting from the saturation of hydrazine and its oxidation products onto the redox-active monolayer film. This type of metallophthalocyanine-SAM-based electrode is a highly promising electrochemical sensor given its ease of fabrication, good catalytic activity, stability, sensitivity and simplicity. 相似文献
36.
T. M. Fedorova S. S. Topol’ V. M. Derkacheva E. A. Luk’yanets O. L. Kaliya 《Russian Chemical Bulletin》2004,53(8):1655-1660
The reaction of acidic form of the substituted icon phthalocyanine complex (3-PhS- 5-But)4pcFe (pcFe) with dioxygen in o-dichlorobenzene in the presence of dichloroacetic acid (HX) was investigated. The oxidation of HpcFeX gives the corresponding radical cation, which was confirmed by the stoichiometry of reduction of the product formed in this reaction with a two-electron reducing agent. The kinetic equation obtained on the basis of dependences of the oxidation rate on the HpcFeX, HX, and O2 concentrations are consistent with the reaction mechanism that implies the formation of a HpcFeX complex with O2 and its transformation to give a radical cation under the action of HX.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1592–1597, August, 2004. 相似文献
37.
Li-Miao Lin Yong-Hang Xu Man Shen Jia-Xin Liang Shuan-Jin Wang Min Xiao Yue-Zhong Meng 《高分子科学》2021,39(3):337-343
A series of semi-aromatic polyesters named as Poly(PO-CHO-PA) were facilely synthesized via ring-opening terpolymerization of biobased cyclohexane oxide(CHO)/propylene oxide(PO)/phthalic anhydride(PA) using economical U1/PPNCl as dual catalyst. The proportion of CHO-PA and PO-PA segments in polymer can be readily altered by changing the feed ratio of CHO/PO because the reactivity ratios of CHO and PO with PA calculated by Fineman-Ross method are comparable. All synthesized amorphous polyesters w... 相似文献
38.
Hiago N. Silva Srgio Hiroshi Toma Artur Luís Hennemann Josu M. Gonalves Marcelo Nakamura Koiti Araki Marcos Makoto Toyama Henrique Eisi Toma 《Molecules (Basel, Switzerland)》2022,27(14)
A new supramolecular electrocatalyst for Oxygen Evolution Reaction (OER) was synthesized from a central multibridging cobalt tetrapyridylporphyrazine (CoTPyPz) species by attaching four [Ru(bpy)2Cl]+ groups. Both CoTPyPz and the tetraruthenated cobalt porphyrazine species, TRuCoTPyPz, form very homogenous molecular films just by dropcasting their methanol solutions onto GCE electrodes. Such films exhibited low overpotentials for O2 evolution, e.g., 560 e 340 mV, respectively, displaying high stability, typically exceeding 15 h. The kinetic parameters obtained from the Tafel plots showed that the peripheral complexes are very important for the electrocatalytic activity. Hyperspectral Raman images taken along the electrochemical process demonstrated that the cobalt center is the primary active catalyst site, but its performance is enhanced by the ruthenium complexes, which act as electron-donating groups, in the supramolecular system. 相似文献
39.
应用激光解吸电离飞行时间质谱法(LDI—TOF—MS)对平面双核酰亚胺酞菁铁相对分子量进行了测定.探讨了3种不同基质对其分析结果的影响,结果发现基质并不能完全解离样品,而不加任何基质的激光质谱得到了理想的结果. 相似文献
40.
The photochemical and photophysical properties of peripheral and nonperipheral zinc and indium phthalocyanines containing 7‐oxy‐3,4‐dimethylcoumarin synthesized were investigated in this study. 7‐Hydroxy‐3,4‐dimethylcoumarin ( 1 ) was synthesized via Pechmann condensation reaction and then the phthalonitrile derivatives [4‐(7‐oxy‐3,4‐dimethylcoumarino)phthalonitrile ( 2 ) and 3‐(7‐oxy‐3,4‐dimethylcoumarino)phthalonitrile ( 3 )] were synthesized by nucleophilic aromatic substitution. Phthalocyanine compounds containing coumarin units on peripheral ( 4 and 5 ) and nonperipheral ( 6 and 7 ) positions were prepared via cyclotetramerization of phthalonitrile compounds. All compounds' characterizations were performed by spectroscopic methods and elemental analysis. The phthalocyanine derivatives' ( 4–7 ) photochemical and photophysical properties were studied in DMF. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties of these novel phthalocyanines ( 4 – 7 ) were studied in DMF. They produced good singlet oxygen (e.g., ΦΔ = 0.93 for 7 ) and showed appropriate photodegradation (in the order of 10?5), which is very important for photodynamic therapy applications. 相似文献