Open Pore Architecture of an Ordered Mesoporous IrO2 Thin Film for Highly Efficient Electrocatalytic Water Oxidation

We report the first accessible channel‐like open pore architecture of ordered 2D hexagonal mesoporous IrO2 films and its utilization as an efficient anode for electrocatalytic water oxidation. A well‐ordered mesostructure of circa 7 nm pores were obtained by a facile one‐pot soft‐templating strategy, employing a [Ir(OH)6]2− precursor stabilized by a triblock copolymer “Pluronic F127” as a pore‐directing template. A mesoporous IrO2 film calcined at 400 °C (∼70 nm thick) affords a high surface area of 512 m2 cm−3 and 2 times higher O2 evolution during the electrocatalytic water oxidation relative to an untemplated IrO2 coating film. Open mesopore architecture for efficient electrocatalysis: Channel‐like open pore architecture of ordered 2D hexagonal mesopores in an IrO2 film is achieved for the first time by a facile one‐pot soft‐templating strategy. The mesoporous IrO2 electrode affords a very high surface area and improves the electrocatalytic performance of water oxidation relative to a conventional nanoparticulate structure of untemplated IrO2 coating.