Influence of Synthesis Techniques on the Size of Nanomaterials: A Comprehensive Review, Mechanisms, and Future Prospects

Abstract

Nanomaterials are widely used today because their small size gives them special physical, chemical, and biological properties. Particle size and shape play a major role, as they affect surface area, optical and magnetic behavior, catalytic activity, and biocompatibility. Therefore, controlling nanoparticle size is crucial for improving performance. This review summarizes major synthesis methods and how they affect nanoparticle size. Top-down physical methods like ball milling and laser ablation are easy and scalable, while bottom-up chemical methods such as sol–gel, co-precipitation, microemulsion, and hydrothermal synthesis allow better control over size and morphology. Green synthesis using plant extracts, microbes, or biomolecules is also discussed as an eco-friendly alternative. The review highlights how different synthesis routes influence particle size, current applications, challenges in consistency and large-scale production, and future directions for creating uniform and sustainable nanomaterials.