Structural properties of ZnO obtained from spent batteries through the Pechini method

GALLEGOS, M.V.; MARCOS MEYER; JORGE SAMBETH; DAMONTE, LAURA C.

Congreso; 19th International Conference on Positron Annihilation; 2022

Zinc oxide is an interesting material with useful applications, such as catalysis, electronics,solar cells, sensors, acoustics, etc. The versatility of this material is related to its structuraland textural properties, which depend on the synthesis methods used. In the Pechini method,a polyhydroxy alcohol (ethylene glycol) and a hydroxycarboxylic acid (citric acid) are used.These form a polymer network in which the metal ions are evenly distributed. During thecalcination stage, the polymer network collapses, and the metal oxide powder remains. Thepowders are extremely pure and very homogeneous compared to powders prepared byconventional methods.Zn is part of alkaline batteries, so the technological possibility of recovering Zn as ZnOprovides an environmental solution. In this work, we intend to recover Zn2+ ions fromexhausted batteries using different acids. Starting from zinc nitrate or zinc chloride solutions,it is intended to synthesize ZnO through the Pechini method.The obtained solids were characterized by X-ray diffraction (XRD), scanning electronmicroscopy (SEM) and diffuse reflectance spectroscopy. The peculiar morphologies observedcould be related to the different counterions in the starting solutions. Positron annihilationlifetime spectroscopy (PALS) was applied to verify the ability of positrons to sense the effectof initial solutions on the morphological and structural properties.