Environmentally Friendly Fabrication of Ti/RuO 2 -IrO 2 -SnO 2 -Sb 2 O 5 Anode with In Situ Incorporation of Reduced TiO 2 Interlayer

The intensive use of chemical reagents in the pretreatment of Ti substrate and shorter electrode life constrict the wider application of the dimensionally stable anode (DSA). In this study, a simple method was developed to thermally pretreat the Ti substrate in the atmosphere of H 2 and N 2 (molar ratio 1:5) without chemicals consumption and wastewater discharge. It was found that the reduced TiO 2 interlayer could be favorably created at temperature of 750 °C. This rendered Ti/reduced TiO 2 /RuO 2 -IrO 2 -SnO 2 -Sb 2 O 5 anode with better stability and higher electrocatalytic activity. The accelerated lifetime for Ti/reduced TiO 2 /RuO 2 -IrO 2 -SnO 2 -Sb 2 O 5 electrode was 65 h with the optimum catalyst loading amount (2.6 ± 0.05 mg cm −2 ), while it was only 50 h for traditional Ti/RuO 2 -IrO 2 -SnO 2 -Sb 2 O 5 electrode. As compared with the counterparts, Ti/reduced TiO 2 /RuO 2 -IrO 2 -SnO 2 -Sb 2 O 5 with higher oxygen evolution potential (1.42 V/SCE) and lower chlorine evolution potential (1.12 V/SCE), suggesting higher electro-catalytic activity toward reactive oxidative species formation. The deactivation test indicates that the anode deactivation mainly proceeded via the dissolution of the catalyst layer and then formation of insulated TiO 2 on the substrate. Generally, an environmentally friendly Ti substrate pretreatment method was developed and demonstrated promising for upgrading DSA fabrication process in industrial application.