Synthesis of Co(OH)2@SiO2 core-shell based silver deposited cobalt oxide nanoflower for rechargeable Zinc-air batteries

Abstract The studies of core-shell nanoparticles have gained significant interests due to the high stability and probable template to form a core-shell complex by coating on them with organic or inorganic substances. The silica nanoparticle covered with cobalt is especially important because it has a chemically stable core. Co3O4-NF was synthesized by the calcination of Co(OH)2@SiO2 under atmospheric air for oxygen reduction and evolution reactions. After calcination, Ag deposition was performed to produce Ag@Co3O4-NF and their surface area reduces from 125.68 to 108.12 m2/g. The crystallanity and morphological features were observed by the X-ray diffraction (XRD) and scanning electron microscopy (SEM). Furthermore, Ag@Co3O4-NF catalysts exhibited superior electrochemical performance as a cathode material for Zinc-air batteries. The cyclic test for charging and discharging was performed for 500 h revealing Ag@Co3O4-NF a potential catalyst, having splendid stability for the OER and ORR.