Interface oxidation induced amorphous/crystalline 1D hollandite Rb0.17IrO2 for efficient oxygen evolution reaction

Recently, surface reconstruction derived from Ir-based derivatives could achieve satisfactory oxygen evolution performance. Herein, ultra-long nanowire hollandite structured Rb 0.17 IrO 2 was synthesized and a nano-amorphous layer with a thickness of ∼1.5 nm was achieved by interfacial oxidation treatment. The prepared catalyst exhibits outstanding water oxidation activity with an oxygen evolution reaction (OER) current density of 10 mA cm −2 at 330 mV for robust continuous operation in acidic media. Through the spectroscopic and density functional theory (DFT) theoretical calculations, we demonstrate that the nano-amorphous layers induced by interfacial oxidation on the one-dimensional (1D)-nanowire surface have enhanced O-2p centers and increased Ir-O hybridization compared to the bulk Rb 0.17 IrO 2 phase, which essentially balances the adsorption energy of the intermediates. Effectively incorporating surface reconstruction behavior could significantly improve catalyst activity. This work effectively combines 1D Ir-based materials and surface reconstruction, which provides a strategy for the subsequent full utilization of Ir-based materials applied on OER process.