Facile Plant Extract Mediated Eco-Benevolent Synthesis and Recent Applications of CaO-NPs: A State-of-the-art Review

Ameliorating the sustainable and eco-accommodating routes for the procurable synthesis of nanoparticles (NPs) is a crucial aspect in the area of green nanotechnology. The known conventional routes for the production of NPs are complicated, noxious, expensive and not safer to human and environment. To overcome these threats, natural precursors such as biopolymers, plant, fungi, and bacteria have been used to fabricate the calcium oxide nanoparticles (CaO-NPs). The shape, size, and applications of the CaO-NPs are prominently affected by the reaction parameters under which they are synthesized. Moreover, the CaO-NPs synthesized by green approach have found potential applications in a wide spectrum of areas including, catalysis, bio-ceramics, additive in refractory, biodiesel production, adsorbent, antimicrobial agent, removal of Cr(VI) and trans esterification of oils. This research study discussed various plants and the different plant parts that have been used for the synthesis of CaO-NPs. The protocol, characterization techniques, mechanism, and eco-benign synthesis of the CaO-NPs along with various recent applications were also discussed.