In:
Materials Science Forum, Trans Tech Publications, Ltd., Vol. 956 ( 2019-6), p. 21-34
Abstract:
In order to obtain a titanium-based PbO 2 electrode with high electrocatalytic activity and good stability, A porous β-PbO 2 electrode is prepared by electrodepositing on titanium substrate Sn-Sb-RuOx coating. The surface morphology and phase analysis of the porous β-PbO 2 electrode prepared at different current density were investigated by SEM and XRD. Results showed that the current density changes the surface morphology and active surface area of the porous β-PbO 2 electrode. When the current density is 2 A/dm 2 , the surface of the porous β-PbO 2 prepared by electrodeposition has a uniform porous morphology with a pore diameter of 50-200 µm with main crystal phase of β-PbO 2 . Influence of current density on the electrochemical activity of the electrode was analyzed using anodic polarization curve, electrochemical impedance spectroscopy and galvanostatic polarization. Results revealed that with the increase of current density, the oxygen evolution potential of the porous β-PbO 2 electrode decreases first and then increases while the exchange current density first increases and then decreases. When the current density is 2 A/dm 2 , the oxygen evolution potential is 2.0075 V(at 0.05 A/cm 2 ) and the maximum exchange current density is 1.77×10 -4 A/cm 2 . According to the electrochemical impedance spectroscopy, when the current density is 2 A/dm 2 , Q f and Q dl are the largest, R f and R ct are the smallest, and the R F first increases and then decreases with the current density increases. When the current density is 2 A/dm 2 , the maximum R F value is 655.7. The results with galvanostatic polarization at current density of 0.05 A/cm 2 showed that the electrode has a minimum electrode voltage of 2.05 V at a current density of 2 A/dm 2 . Accelerated life experiments were carried out in 2 g/L Cl - and 150 g/L H 2 SO 4 bath at 25 °C, and the porous β-PbO 2 electrode obtained under the current density of 2 A/dm 2 has the longest life, and the electrode life is 68 h, which is 2.5 times of the PbO 2 electrode obtained under the current density of 4 A/dm 2 .
Type of Medium:
Online Resource
ISSN:
1662-9752
DOI:
10.4028/www.scientific.net/MSF.956
DOI:
10.4028/www.scientific.net/MSF.956.21
Language:
Unknown
Publisher:
Trans Tech Publications, Ltd.
Publication Date:
2019
detail.hit.zdb_id:
2047372-2
