RuO2/IrO2 nanoparticles decorated TiO2 nanotube arrays for improved activity towards chlorine evolution reaction

Abstract

Dimensionally stable anodes (DSA) have been extensively employed for industrial chlorine evolution reactions (CER). Many efforts have been made to develop nanostructured DSA electrodes to enhance the stability and catalytic activity of CER. Herein, a composite catalyst composed of RuO2/IrO2 decorated TiO2 nanotube arrays (TiO2 NTAs) was proposed for CER applications. 1D TiO2 NTAs were fabricated by electrochemical anodization. RuO2/IrO2 nanoparticles were embedded in TiO2 NTAs by electrochemical deposition. Catalytic activity of RuO2/IrO2-TiO2 NTAs is superior to most CER materials. At a current density of 50 mA cm−2, the overpotential is 1.115 V (vs. SCE) with a Tafel slope of 33.5 mV dec−1 in 5 M NaCl. The RuO2/IrO2-TiO2 NTAs exhibit good selectivity towards oxygen evolution reaction, with a potential separation of 205 mV at 50 mA cm−2. The RuO2/IrO2-TiO2 NTAs also display excellent stability for CER. Almost no attenuation is observed after 50 h test.