Transition metallic oxides, which embody many stoichiometric variations, are fashioned into varied crystal buildings by the atomic association of cations and anions based on stoichiometric composition and are used for a variety of purposes based mostly on this. Amongst them, cobalt oxide, which has large crystal buildings relying on lattice factors of anion and the valence of Co cation, from its hydroxide components, is attracting lots of consideration on account of its attention-grabbing catalytic properties on account of its crystal construction. On this examine, utilizing the synthesized Co(OH)2 nanosheets, the real-time habits of the part transition that happens when steady warmth is utilized to the pattern has been systematically analyzed utilizing an aberration-corrected scanning transmission electron microscope. The layered Co(OH)2 part passes by way of hexagonal CoO and cubic CoO phases to lastly change into Co particles, however when the temperature is dropped within the hexagonal part, spinel Co3O4 is fashioned. These outcomes recommend that varied phases included in transition metallic oxides could be selectively carried out based on temperature vary management.