화학공학소재연구정보센터
Electrochimica Acta, Vol.55, No.27, 8197-8206, 2010
Stable spinel type cobalt and copper oxide electrodes for O-2 and H-2 evolutions in alkaline solution
The stability of one material Ti/CuxCo3-xO4 as anode and also cathode was investigated for electrolysis of alkaline aqueous solution The electrodes were prepared by thermal decomposition method with x varied from 0 to 1 5 The accelerated life test illustrated that the electrodes with x = 0 3 nominally showed the best performance with a total service life of 1080 h recorded in 1 M NaOH solution under alternating cui rent direction at 1 A cm(-2) and 35 degrees C The effects of copper content in electrode coating were examined in terms of electrode stability surface morphology coating resistivity and coating compositions The presence of Cu in the spinel structure of Co3O4 could significantly enhance the electrochemical and physicochemical properties The trends of crystallographic properties and surface morphology have been analyzed systemically before during and after the electrodes were employed in alkaline electrolysis The oxygen evolution would lead to the consumption of the coating material and the progressive cracking of the coating Along with hydrogen evolution cobalt oxide could be reduced to metal Co and Co(OH)(2) with particle sizes changed to smaller values in crystal and/or amorphous form at the cathode The formation of Co is the key process for this electrode to serve as both anode and cathode It is also the main reason leading to the eventual failure of the electrodes (C) 2010 Elsevier Ltd All rights reserved