A novel modified electrode was prepared by electrochemicaly cycling scanning the glass carbon electrode covered with a macroporous alumina membrane in a solution containing PPy and PMo 12O 3- 40. The reversibility of ...A novel modified electrode was prepared by electrochemicaly cycling scanning the glass carbon electrode covered with a macroporous alumina membrane in a solution containing PPy and PMo 12O 3- 40. The reversibility of the cyclic voltammograms was improved obviously. The remarkable advantage of the modified electrode was the high sensitivity and favorable electrocatalytic behavior toward NO - 2. The peak current increased linearly with the concentration of NO - 2 in the range of 8.0×10 -7—0.01 mol/L. The detection limit of NO - 2 was 1.0×10 -9 mol/L. The polyoxometalates nanopaticles modified electrode exhibited almost the same electrochemical behavior after 7 d. It is indicated that the PMo 12-PPy/AGCE has a good reproducibility, stability and wide linearity range.展开更多
The interaction sites between microperoxidase-8(MP-8) and Eu^3+ was determined using electrochemical techniques. It is found that two Eu^3+ ions would coordinate strongly with carboxylate oxygen of two propionic acid ...The interaction sites between microperoxidase-8(MP-8) and Eu^3+ was determined using electrochemical techniques. It is found that two Eu^3+ ions would coordinate strongly with carboxylate oxygen of two propionic acid groups of the heme group in an MP-8 molecule, leading to the increase in the reversibility of the electrochemical reaction of MP-8. The excessive Eu^3+ ions weakly interact with the oxygen containing groups in the peptide chain of MP-8.展开更多
文摘A novel modified electrode was prepared by electrochemicaly cycling scanning the glass carbon electrode covered with a macroporous alumina membrane in a solution containing PPy and PMo 12O 3- 40. The reversibility of the cyclic voltammograms was improved obviously. The remarkable advantage of the modified electrode was the high sensitivity and favorable electrocatalytic behavior toward NO - 2. The peak current increased linearly with the concentration of NO - 2 in the range of 8.0×10 -7—0.01 mol/L. The detection limit of NO - 2 was 1.0×10 -9 mol/L. The polyoxometalates nanopaticles modified electrode exhibited almost the same electrochemical behavior after 7 d. It is indicated that the PMo 12-PPy/AGCE has a good reproducibility, stability and wide linearity range.
文摘The interaction sites between microperoxidase-8(MP-8) and Eu^3+ was determined using electrochemical techniques. It is found that two Eu^3+ ions would coordinate strongly with carboxylate oxygen of two propionic acid groups of the heme group in an MP-8 molecule, leading to the increase in the reversibility of the electrochemical reaction of MP-8. The excessive Eu^3+ ions weakly interact with the oxygen containing groups in the peptide chain of MP-8.
文摘以碳酸锰(Mn CO_3)为前体,空气氛围下采用不同温度(300℃、350℃、400℃)煅烧,制备了3种介孔二氧化锰(Mn O_2)材料,分别与粘结剂混合喷涂至石英晶片作为电极,利用石英晶体微天平(QCM)监测了3种材料在0.1 mol/L Na_2SO_4溶液中随循环伏安过程的电化学性能变化。分析结果表明,3种材料在首圈循环中都呈现出显著的质量增加,发生了不可逆反应过程;300℃煅烧制备的Mn O_2材料具备更好的电化学稳定性和容量保持能力。将300℃,350℃和400℃煅烧的Mn O_2各自作为正极与活性炭负极组成超级电容器,进行充放电测试,首圈均有35%~40%的容量损失;三者稳定循环时放电容量分别为15.9,12.9和11.7 m A h/g。QCM的分析与充放电测试结果相一致,表明QCM可用于比较不同介孔二氧化锰材料的电化学性能。
