A Study on the Catalytic Activity and Service Lifetime of RuO2‐TiO2 Composite Electrode with TNTs as Interlayer

Abstract

AbstractHerein, we reported a novel RuO2‐TiO2 composite electrode prepared by thermal decomposition process using TiO2 nanotube arrays (TNTs) as an interlayer. Specifically, the TNTs interlayer was fabricated by anodic oxidation on pure Ti plate, followed by heat‐treatment (450 °C) to transform its amorphous structure to anatase structure. This TNTs interlayer not only has a good protection for Ti substrate, but also has a low resistance. The resultant RuO2‐TiO2 electrode presents superior performance toward chlorine evolution reaction (ClER) and longer service lifetime (132 h) than that without interlayer (59 h). Experimental results show that anodizing time determines the length of TiO2 nanotubes and brings about different catalytic activity and stability. The RuO2‐TiO2/TNTs/Ti electrode with an optimal RuO2‐TiO2 coating (4.5 g m−2) presents a better spatial structure, homogeneous crystal particles, uniformly distribution and more active sites. However, high calcination temperature (>600 °C) has a detrimental impact, i. e. the collapse of TNTs and a “cracked mud” structure, which provide a path for oxygen and electrolyte to penetrate into the substrate and cause the spalling of coating, eventually lead to a serious decline in electrocatalytic activity and stability.