| 초록 |
We synthesized three-dimensional ordered nanoporous mesh-like (3D-NM) nickel electrode by the photolithography method, which outperforms conventional porous nickel electrode. We investigated that fast bubble formation/detachment from the pore can reduce the bubble blocking effect, which disturbs supply of electrolyte to the catalyst surface. In line with the size of bubbles, impedance during the OER with 3D-NM nickel electrode smoothly undergoes while the nickel foam shows unstable graph. Overpotential measured at 10 mA cm-2 was 372 mV and the calculated Tafel slope was 94.4 mV dec-1. Through the unique nanoporous structure of nickel electrode, outstanding stability for 50 hours was achieved. To further improve the OER activity of as-prepared 3D-NM nickel electrode, the decoration of nickel and iron was conducted. The final 3D-NM NiFe electrode showed 261 mV of overpotential at 10 mA cm-2 with 43.8 mV dec-1 of Tafel slope. |
