Synthesis of yeast-assisted Co3O4 hollow microspheres—A novel biotemplating technique

A novel technique for synthesis of biomorphic Co3O4 hollow microspheres, using yeasts as bio-templates, has been successfully developed. Yeast cells were first coated with cobalt hydroxide chloride and then calcined to remove the templates for obtaining Co3O4 hollow microspheres. The prepared products were examined by SEM, XRD and FT-IR for detailed structures. The SEM analysis showed that the products fully retained the morphology of the yeast cells and the size of the hollow microspheres was about 3.7 μm in length and 2 μm in width; XRD indicated that Co3O4 hollow microspheres were of cubic phase; FT-IR revealed that some inherent functional groups on the surface of yeast cells, such as carbonyls, amines and hydroxyls etc., played major roles in the formation of Co3O4 hollow microspheres. A possible formation mechanism of Co3O4 hollow microspheres was proposed.