This report investigated synthesis of porous Ti sheets by direct powder rolling followed by vacuum sintering at 1100°C for 1.5 h. Uniform microstructures were observed in the sections longitudinal and transverse to rolling direction in terms of porosity, pore size, gas permeability and filtration efficiency. IrO2 nanowire arrays were coated onto the powder-rolled porous Ti substrate as an electrode by thermal decomposition. Characterisation results show that the coating mainly exhibited mixture of IrO2 and α-Ti phases. The coating of IrO2 nanowire arrays effectively increased the specific surface area of the IrO2/Ti electrode and reached over 95% of current efficiency. The cyclic voltammetry test of the electrode showed an obvious redox peak due to its increased specific surface area by the porous Ti substrate.
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