if you opt for material science the bestthing is to go for research but you can do masters and might get a job in the Research and development section of some company.
you can also get job after bachelors but that would be field job

Nanotechnology is new in India now so it has not the good scope now a days. but In the comparision of Nanotechnology Meterial Science has good scope in future.And it is increasing day by day.