Promising Green Method for Preparing Nano-Particles and their Famous Applications: A Review

Nanoparticles are promising materials for a wide range of uses, including energy storage and cleaning up the environment, since they have amazing redox properties, are chemically stable, and have a huge surface area. Traditional synthesis methods, on the other hand, have difficulties with safety and the environment because they often employ harmful chemicals and need a lot of energy. As a result, green synthesis has become one of these alternatives. It uses biological resources like microbes, plant extracts, and biopolymers. This paper goes into detail on the most recent developments in the ecologically friendly synthesis of Co₃O₄ nanoparticles, including essential approaches as those that use plants, microbes, and biopolymers. We employ particle size, shape, surface area, response time, yield, and functional performance to compare and contrast different techniques. The article goes on to discuss about how Co₃O₄ is used in photocatalysis, wastewater treatment, supercapacitors, and battery systems. It also talks about common ways to characterize it, such as XRD, SEM, FTIR, UV-Vis, and BET. We also look at some of the challenges that are happening right now, such as not being able to scale up, not having enough lifecycle evaluations, and not having clear procedures. The last part of the report talks about some ways that the authors think could lead to big improvements in hybrid materials, large-scale manufacturing, and sustainability indicators. The main purpose of this assessment is to support the growth of green nanotechnology and encourage its use in practical solutions for energy and the environment.