Question

How an electroscope work and what material is required to make this??

Answer 1

An object with a suspected static electric charge is brought near the metal plate or ball of the electroscope. Electrical charges move to the metal and down to the foil leaves, which then repel each other. Since each leaf has the same charge (positive or negative), they repel each other.

An electroscope is made from conducting material (generally metal). Charge is free to flow on a conductor, and if you put charge at a particular point it will distribute itself over the surface of the conductor.