Nano materials are chemical substances or materials that are manufactured and used at a very small scale (down to 10,000 times smaller than the diameter of a human hair). Nano materials are developed to exhibit novel characteristics such as increased strength, chemical reactivity or conductivity, compared to the same material without nanoscale features.

Nanoscale particles are not new in either nature or science. However, the recent leaps in areas such as microscopy have given scientists new tools to understand and take advantage of phenomena that occur naturally when matter is organized at the nanoscale. In essence, these phenomena are based on “quantum effects“and other simple physical effects such as expanded surface area. In addition, the fact that a majority of biological processes occur at the nanoscale gives scientists models and templates to imagine and construct new processes that can enhance their work in medicine, imaging, computing, printing, chemical catalysis, materials synthesis, and many other fields.

Nanotechnology is not simply working at ever smaller dimensions; rather, working at the nanoscale enables scientists to utilize the unique physical, chemical, mechanical, and optical properties of materials that naturally occur at that scale.

Hence, the main physical changes that take place at the nano scale are as follow:

1. Increase in relative surface area, and
2. Quantum effects.

These factors can change or enhance properties such as reactivity, strength and electrical characteristics. With decrease in size of particle, a greater number of atoms are found at the surface as compared to those inside.