The surface properties of GCE treated by anodic polarization in strong alkaline solutions are makedly different from that of polished GCE. XPS results show thta more oxygenic groups as carbonyl and accid anhydride are...The surface properties of GCE treated by anodic polarization in strong alkaline solutions are makedly different from that of polished GCE. XPS results show thta more oxygenic groups as carbonyl and accid anhydride are formed on the electrode surface, the ratio of O/C increases, C1s and O1s peaks shift to higher binding energies. Moreover, the adsorptivity of the treated GCE decreases and shows no obvious adsorption for Fe2+ in H2SO4 solution. On the other hand, behaviour of the electrode reaction is also prominently improved. The background current is less, the electron transfer rate is greatly speeded up and the reverse of the electrode reaction for Fe3+/2+, Eu3+/2+ is effectively enhanced for treated GCE.展开更多
The electrochemical behavior of rhein modified glassy carbon electrodes were studied. Three peaks in CV appeared in the potential rang of +0.4\-0.8 V\%（vs\%. Ag/AgCl） in 0.06 mol/L H\-2SO\-4. p\-1 and p\-3 are a cou...The electrochemical behavior of rhein modified glassy carbon electrodes were studied. Three peaks in CV appeared in the potential rang of +0.4\-0.8 V\%（vs\%. Ag/AgCl） in 0.06 mol/L H\-2SO\-4. p\-1 and p\-3 are a couples of oxidation\|reduction peak, the electrode process contains two electrons and two protons. The formal potential（\%E\%\+\{o\} ）is -0.202 V（\%vs\%. Ag/AgCl） at the scanning rate of 50 mV/s. The cathodic peak potential shifts linearly in the negative direction with increasing solution pH with a slope of 67 mV per pH unit. The rhein modified electrode shows an electrocatalytic activity for reduction of hemoglobin in 0.06 mol/L H\-2SO\-4 solution. The peak currents are proportional to the concentrations of the hemoglobin in the range of 6.0×10\+\{-8\}\1.3×10\+\{-6\} mol/L, the relative standard deviation is 3.5% for 6 successive determination of 1.0×10\+\{-7\} mol/L hemoglobin solution. The catalytic mechanism has been discussed.展开更多
文摘The surface properties of GCE treated by anodic polarization in strong alkaline solutions are makedly different from that of polished GCE. XPS results show thta more oxygenic groups as carbonyl and accid anhydride are formed on the electrode surface, the ratio of O/C increases, C1s and O1s peaks shift to higher binding energies. Moreover, the adsorptivity of the treated GCE decreases and shows no obvious adsorption for Fe2+ in H2SO4 solution. On the other hand, behaviour of the electrode reaction is also prominently improved. The background current is less, the electron transfer rate is greatly speeded up and the reverse of the electrode reaction for Fe3+/2+, Eu3+/2+ is effectively enhanced for treated GCE.
文摘The electrochemical behavior of rhein modified glassy carbon electrodes were studied. Three peaks in CV appeared in the potential rang of +0.4\-0.8 V\%（vs\%. Ag/AgCl） in 0.06 mol/L H\-2SO\-4. p\-1 and p\-3 are a couples of oxidation\|reduction peak, the electrode process contains two electrons and two protons. The formal potential（\%E\%\+\{o\} ）is -0.202 V（\%vs\%. Ag/AgCl） at the scanning rate of 50 mV/s. The cathodic peak potential shifts linearly in the negative direction with increasing solution pH with a slope of 67 mV per pH unit. The rhein modified electrode shows an electrocatalytic activity for reduction of hemoglobin in 0.06 mol/L H\-2SO\-4 solution. The peak currents are proportional to the concentrations of the hemoglobin in the range of 6.0×10\+\{-8\}\1.3×10\+\{-6\} mol/L, the relative standard deviation is 3.5% for 6 successive determination of 1.0×10\+\{-7\} mol/L hemoglobin solution. The catalytic mechanism has been discussed.
