Highly active, durable and pH-universal hybrid oxide nanocrystals for efficient oxygen evolution

The development of an active, durable, and low-cost catalyst remains hitherto a grand challenge in energy conversion technologies. Herein, hybrid Ptx-NiMnO3 nanocrystals (NCs) (x = 0.1, 0.5, and 1.0 mM) were synthesized by a modified citrate-gel approach and utilized as efficient catalysts towards the oxygen evolution reaction (OER). The results showed that the size of Ptx-NiMnO3 NCs decreases with increasing the initial concentration of Pt. Meanwhile, the OER activity and durability of the as-synthesized Pt-NiMnO3 under different pH conditions are found to be Pt-content-dependent. Particularly, Pt1-NiMnO3 showed superior OER efficiency relative to its counterparts Pt0.5-NiMnO3, Pt0.1- NiMnO3, NiMnO3, and commercial Pt/C at different pH values, ascribed to the size, morphology, and composition effects as confirmed via XRD, XPS and electrochemical characterization.