Environmentally Friendly Fabrication of Ti/RuO₂-IrO₂-SnO₂-Sb₂O₅ Anode with In Situ Incorporation of Reduced TiO₂ Interlayer

Abstract

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 H2 and N2 (molar ratio 1:5) without chemicals consumption and wastewater discharge. It was found that the reduced TiO2 interlayer could be favorably created at temperature of 750 °C. This rendered Ti/reduced TiO2/RuO2-IrO2-SnO2-Sb2O5 anode with better stability and higher electrocatalytic activity. The accelerated lifetime for Ti/reduced TiO2/RuO2-IrO2-SnO2-Sb2O5 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/RuO2-IrO2-SnO2-Sb2O5 electrode. As compared with the counterparts, Ti/reduced TiO2/RuO2-IrO2-SnO2-Sb2O5 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 TiO2 on the substrate. Generally, an environmentally friendly Ti substrate pretreatment method was developed and demonstrated promising for upgrading DSA fabrication process in industrial application.

Preparation of Ti/IrRuSnSbOx Electrodes by a Hydrosol Process for Efficient and Stable Chlorine Evolution Reaction

“…In Figure b, the diffraction peaks of Ti and the solid solution peaks of Ir, Ru, Sn, and Sb were clearly identified. The diffraction peaks at 27.7, 34.5, 39.5, and 53.5° corresponded to the solid solution peaks (110), (101), (200), and (211) of IrO 2 , RuO 2 , SnO 2 , and Sb 2 O 4 , respectively . Compared with MMO A , the diffraction peaks of (110) and (101) shifted slightly to a lower angle.…”

“…The diffraction peaks at 27.7, 34.5, 39.5, and 53.5°corresponded to the solid solution peaks (110), ( 101), (200), and (211) of IrO 2 , RuO 2 , SnO 2 , and Sb 2 O 4 , respectively. 26 Compared with MMO A , the diffraction peaks of ( 110) and ( 101) shifted slightly to a lower angle. The negative shift of diffraction peaks was due to lattice expansion, which might be related to solid solution and doping (Ir 4+ , 63 pm; Ru 3+ , 68 pm; Ru 4+ , 62 pm; Sn 4+ , 69 pm; Sb 3+ , 62 pm; and Sb 5+ , 92 pm).…”

Anode Boundary Layer Extraction Strategy for H+–OH– Separation in Undivided Electrolytic Cell: Modeling, Electrochemical Analysis, and Water Softening Application

“…In the undivided electrolytic cell, a tubular stainless-steel cathode (height 20 cm, diameter 8 cm) and a tubular Ti porous anode (height 20 cm, diameter 4 cm, pore diameter 5 μm) were concentrically placed in a Plexiglas cylinder with a distance of 20 mm (Figure ). The tubular Ti porous anode was coated with a RuO 2 –IrO 2 –SnO 2 –Sb 2 O 5 mixed catalyst layer using the Pechini method reported in our previous study to make it more stable . The synthetic electrolyte of 10.0 mM Na 2 SO 4 was pumped into the reactor by a peristaltic pump, and the solution in the internal chamber of the Ti anode was extracted by an another peristaltic pump.…”

“…The tubular Ti porous anode was coated with a RuO 2 −IrO 2 −SnO 2 −Sb 2 O 5 mixed catalyst layer using the Pechini method reported in our previous study to make it more stable. 31 The synthetic electrolyte of 10.0 mM Na 2 SO 4 was pumped into the reactor by a peristaltic pump, and the solution in the internal chamber of the Ti anode was extracted by an another peristaltic pump. So a pressure difference could be created between the internal chamber of the Ti anode filter and bulk solution.…”

A Novel Trimetal Phosphide with Amorphous Porous Structure for the Enhanced Electrocatalysis of Oxygen Evolution Reaction

“…4,5 At present, noble metal-based electrocatalysts are considered to be very effective catalysts for OER, such as iridium and rutheniumbased composite materials. 6 However, these noble metal-based catalysts have the disadvantages of high cost, limited raw material and poor stability. Therefore, it is in great urgent to develop economical, efficient, and stable electrocatalyst for water splitting.…”