Green Synthesis of Co3O4 Catalysts Using Jasmine Flower Extract for the Effective Hydrolysis of NaBH4

Green synthesis is an important route in the preparation of bare metals and metal oxides that provides cost-effective, eco-friendly, and highly efficient catalysts for catalyzing various reactions. In this paper we report, for the first time, the green synthesis of Co₃O₄ employing jasmine flower extract as a green precursor for the application as catalyst during NaBH₄ hydrolysis. Moreover, the role of calcination temperature (300–900 °C) on stability, morphology, texture, and catalytic performance of the formed Co₃O₄ have been addressed too. Co₃O₄ was found to be the major formed phase together with trace quantities of graphitic carbon over the 300–700 °C range. Pushing the calcination temperature to 900 °C was associated with a thermal reduction of Co₃O₄ to CoO and the elimination of the graphitic carbon. The highest activity was obtained using the 700 °C calcined catalyst (4449 ml g^− 1 min^− 1 at 45 °C).

Graphical Abstract

Representation of the green synthesis strategy followed during the synthesis of Co₃O₄ NPs and its application as a catalyst for the hydrogen generation via the hydrolysis of sodium borohydride