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Perovskite oxides possess high intrinsic activity toward oxygen evolution reaction (OER), while their catalytic activities have been restricted by the low surface area and poor conductivity. Herein, we report binder-free LaCoO3 perovskite nanosheets vertically grown on the nickel foam as an OER catalyst with enhanced performance and stability in alkaline electrolytes. The proposed catalyst displays an outstanding performance to achieve the current density of 10 mA cm–2 at the overpotential of 342 mV, while 390 mV is required for the bulk LaCoO3 prepared by conventional methods. The enhanced OER activity is mainly because the nanosheet structures have increased surface areas and enhanced conductivity and charge transfer. Moreover, the porous structure formed by vertically aligned nanosheets increases surface wettability, which enables the rapid dissipation of gas bubbles along with excellent durability. This work proposes an approach to unlocking the high intrinsic activity of perovskites for OER.

Three-dimensional CT imaging should be considered prior to C1 pedicle screw fixation in patients with ponticulus posticus, to avoid mistaking the ponticulus posticus for a widened dorsal arch of the atlas. If there is no ponticulus posticus syndrome preoperatively, C1 pedicle screw fixation can be successfully performed without removing the bony anomaly.