Controlled Synthesis of NiO and Co₃O₄ Nanoparticles from Different Coordinated Precursors: Impact of Precursor’s Geometry on the Nanoparticles Characteristics

Abstract

Metal oxide nanoparticles are of great technological relevance because of their wide applications in catalysis and photonics. Herein, we report a one-pot method to synthesize transition metal oxide nanoparticles such as NiO and Co3O4 via solid state thermal decomposition of their analogue coordinated metal precursors without stirring and washing. The significance of the reported method is represented in its purity without washing and the systematic production. The impact of precursor structure on the characteristics of the nanoparticles was investigated. Variation of the precursor geometry affected the morphology of the nanoparticles from spherical to pyramidal upon changing the geometry from octahedral to square-pyramidal, respectively. The synthesized nanoparticles were characterized by XRD, XPS, N2 sorpometry, UV–vis, and SEM. The photocatalytic activity of the prepared nanoparticles was assessed toward the photodegradation of methylene blue dye as a model pollutant. The nanoparticles exhibited superior photocatalytic efficiency in the trend of NiO > Co3O4. The morphology–photoefficiency relationship was investigated. The reported method herein would provide a potential facile route for fabricating other metal oxides with controllable morphology.