CL20250802_001_Co3O4#48_after_1h_CA_0p8V_CV_5mVpsec_0p1M_KOH2

Elab Identifier: , Preparation Procedure: The Co₃O₄ nanoparticle electrodes with a high catalyst loading (42.7 µg cm-2) were fabricated by drop-casting 100 µL of Co₃O₄ ink onto a gold-coated quartz crystal microbalance (QCM) resonator, which served as the substrate. The ink was prepared by dispersing Co₃O₄ nanoparticles in Milli-Q water to achieve a concentration of 0.5 mg mL⁻¹.