ABSTRACT
The European Union has issued legislation on waste electrical/electronic equipment and restriction of hazardous substances, which come in parallel with the worldwide enlargement demands, industrial requirements, and forthcoming technologies that depend mainly on nanoparticles. Thus, there is an imperative need to develop an eco-friendly approach for nanomaterials synthesis that does not depend on toxic chemicals. Plants and microorganisms (i.e., algae, bacteria, yeast, and fungi) with their components are acting as biofactories for metal oxides (Yadav et al., 2019).
