Bimetallic IrxCo1−x alloy nanotubes (x = 0.25, 0.50 and 0.75, the atomic ratios of Ir precursor out of the total metal precursor) were prepared via the thermal H2-reduction of IrxCo1−xOy nanotubes which were synthesized by electrospinning and post calcination. Ir and Co atoms were well mixed to form the alloy in IrxCo1−x nanotubes. Their phase structures were different depending on the composition ratios. Ir0.75Co0.25 and Ir0.50Co0.50 had Ir fcc phase where some Ir atoms were substituted with Co. In contrast, Ir0.25Co0.75 was in Ir-substituting Co hcp phase. Among the IrxCo1−x alloy nanotubes, Ir0.50Co0.50 showed the highest catalytic activity for overall electrochemical water splitting in acidic, neutral, and alkaline conditions, better than pure metallic Ir and Co counterparts. The activity and stability of Ir0.50Co0.50 nanotubes for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) were superior to commercial Ir/C and Pt/C, respectively.
Bibliographical noteFunding Information:
This work was financially supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science, ICT and Future Planning (NRF‐2020R1A2B5B01001984) and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF‐2018R1A6A1A03025340).
National Research Foundation of Korea (NRF), Grant/Award Numbers: NRF‐2018R1A6A1A03025340, NRF‐2020R1A2B5B01001984 Funding information
© 2021 Korean Chemical Society and Wiley-VCH GmbH.
- alloy nanotube
- overall water splitting
- pH-universal catalyst