Green synthesis of Co3O4 nanoparticles via Aspalathus linearis: Physical properties

ABSTRACT This study reports on the bio-synthesis and the main physical properties of p-type Co3O4 nanoparticles for the first time by a completely green chemistry process using Aspalathus linearis's natural extract as an effective chelating agent. Their surface/interface and optical properties are reported. In addition to the X-ray diffraction investigations, the Raman, and infrared as well as X-ray photoelectron spectroscopies confirmed the single phase of the Co3O4 nanoparticles. As their average size can be as low as ⟨φparticle⟩ ∼3.6 nm, the reticular atomic plans are under a slight compressive state.