ZnO nanoparticles preparation from spent zinc–carbon dry cell batteries: studies on structural, morphological and optical properties

Recovery and recycling of valuable materials from battery waste is challenging as well as important from economic and environmental point of view. In this work, spent zinc–carbon batteries were processed with HCl and NaOH to synthesize ZnO nanoparticles. ZnO nanopowders were also prepared by using ZnCl2 as precursors with varying amount of NaOH using sol–gel method. In both cases, ZnO nano particles were characterized with XRD, XRF, FESEM, EDAX, particle size analyzer and UV–visible (UV–Vis) spectroscopy. The purity of the synthesized ZnO from spent zinc–carbon batteries was found to be 99.69%. FESEM micrographs showed the reduction in particle size from 50 nm to 20 nm with a decrease in NaOH concentration. UV–Vis study showed significant peak shift with maximum absorption…