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

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 RuO 2 /IrO 2 decorated TiO 2 nanotube arrays (TiO 2 NTAs) was proposed for CER applications. 1D TiO 2 NTAs were fabricated by electrochemical anodization. RuO 2 /IrO 2 nanoparticles were embedded in TiO 2 NTAs by electrochemical deposition. Catalytic activity of RuO 2 /IrO 2 -TiO 2 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 RuO 2 /IrO 2 -TiO 2 NTAs exhibit good selectivity towards oxygen evolution reaction, with a potential separation of 205 mV at 50 mA cm −2 . The RuO 2 /IrO 2 -TiO 2 NTAs also display excellent stability for CER. Almost no attenuation is observed after 50 h test. • RuO 2 /IrO 2 distributed in 1D TiO 2 nanotube arrays exhibit excellent CER activity. • RuO 2 serves as the main electron donor to improve conductivity and CER activity. • IrO 2 enhances the selectivity and significantly improves the stability of CER. • The large surface area and direct electron transfer pathway is beneficial for CER.