Our group proposes to construct a nano-Au-ZrOx (x<2) cathode in high-temperature SOEC through high voltage activation. Here we dispersed a Au layer into Au nanoparticles (down to 2 nm) at 800 °C by applying high voltages. A 75-fold decrease in the polarization resistance was observed, accompanied by a 38-fold improvement in the cell current density. The above result was published in Nano Letters.