Lignin-based monolithic carbon electrode decorating with RuO2 nanospheres for high-performance chlorine evolution reaction

Abstract

One of the primary challenges of the chlor-alkali industry is the passivation of Ti electrode during the electrolysis process. Therefore, a renewable electrode with abundant active sites but without a passivation layer was necessary to address this issue. In this work, lignin and acetylene black were applied to fabricate a self-standing and low-resistance carbon electrode as a conductive substrate. Then, RuO2 nanospheres were decorated on the surface of the carbon electrode by an electrochemical deposition and electrochemical oxidation process for the high-performance chlorine evolution reaction. The results indicated that the carbon electrode possessed high mechanical strength and desired shape without any binders. More significantly, it was revealed that the RS of the optimized carbon electrode was only 0.91 Ω which was comparable in conductivity to the commercial carbon cloth. The RuO2/CE-10 % had abundant active sites and the current density could reach to 129 mA cm−2 at 1.2 V, which was attributed to the RuO2 nanospheres with huge specific surface area and excellent catalytic activity. Our work demonstrated the successful conversion of biomass waste into the high-performance chlorine evolution electrode, and its promising catalytic activity further suggested the developed approach may provide a positive route to solve the issue of passivation layer.