Distinction of Conductive PbO_2 and Non-conductive PbSO_4 in Deposited Mixtures on IrO_2-Ta_2O_5/Ti Anodes Using SEM with Low Accelerated Incident Electrons

摘要

SEM observation at a low accelerated electron beam such as at 1 keV successfully distinguished conductive PbO_2 from non-conductive PbSO_4 which are deposited as the mixture on the IrO_2-Ta_2O_5/Ti anode after the electrolysis in the acidic solution containing Pb (Ⅱ). Although brightness in SEM images is generally affected by shape and conductivity of the sample, the SEM images in this study were observed at the same area of the sample by changing the acceleration voltage of the electron beam. Therefore, SEM observation at 1 keV indicates that the depth of the electron beam more clearly reflects the difference in conductivity which is given as the difference in brightness. The SEM measurement technique shown in this study is helpful for the similar situation that the target for analysis is the mixture containing compounds that are difficult to distinguish by characteristic X-ray.