掺杂Co(OH)_2对超级电容器正极材料Ni(OH)_2性能的影响

采用电化学共沉积法在泡沫镍基体上制备了掺杂Co(OH)2的纳米级Ni(OH)2电极。采用XRD、SEM、EDS等分析表征了电极材料的晶体结构、成分和形貌;采用恒流充放电、循环伏安及交流阻抗等方法测试了其电化学性能。结果表明,电化学共沉积法可以制备定量掺杂Co(OH)2的α-Ni(OH)2,该电极材料具有三维纳米花状结构;适当掺杂Co(OH)2的α-Ni(OH)2可以显著提高电极的比容量和循环性能,还提高了放电电位和氧气析出过电位,同时提高了其质子扩散系数和降低了扩散阻抗。     

AOT reverse micelle, a new organized medium for the electrosynthesis of polyaromatic hydrocarbons; application to the electropolymerization of biphenyl

Electrosynthesis of poly(biphenyl) (PBP) films was performed in an AOT [sodium bis(2-ethylhexyl) sulfosuccinate] reverse micelle by cyclic voltammetry and chronopotentiometry on a platinum electrode. An electroactive PBP film was formed either by cyclic voltammetry between −0.6 and 1.65 V/Ag/AgCl or under current control (j = 0.2 mA/cm²). PBP films were characterized electrochemically and spectroscopically (MALDI-TOF mass spectrometry), NMR, Raman, FT-IR, X-ray photoelectron and UV–vis spectroscopy). The structure of the PBP films involved sequences of ramified trimer possessing quinoid forms. This type of sequences can give strongly condensed oligomers with PBP molar mass up to 2669.6 g/mol according to the electrosynthesis charge.     

Cobalt(III) complexes of macrocyclic-bidentate type as a new group of corrosion inhibitors for iron in perchloric acid

A new class of corrosion inhibitors for iron demonstrated by group of cobalt complex compounds, of the general formula [Co^III(Rdtc)cyclam](ClO₄)₂ (1)-(4) where cyclam is 1,4,8,11-tetraazacyclotetradecane and Rdtc⁻ refer to piperidine-, 2-, 3- or 4-methylpiperidine-dithiocarbamates, respectively, has been studied. Investigation of inhibiting properties of the ligands themselves as well as their corresponding complexes with Co(III) ion, was performed in 0.1 M HClO₄ by potentiodynamic polarization and EIS measurements. Cobalt complexes inhibit the corrosion of iron better than the uncomplexed ligands. Polarization curves suggest that complexes and amino-ligands are mixed-type and cathodic-type inhibitors, respectively. The impedance of the inhibited substrate increased with increasing concentration of inhibitor. An equivalent circuit is suggested, based on the analysis of EIS spectra. Using molecular modeling calculations, the complex compounds were characterized in terms of their structural properties and inhibition activity.