What is the other type of fissionable material which can be used in nuclear fission processes?

Various type of radioactive material like plutonium can be used as a fissionable material. However, ordinary uranium consists only of about 0.7 percent of U²³⁵ and it is extremely difficult to isolate U²³⁵ from the other isotopes present in the ordinary uranium. As a result plutonium is prepared from the abundant isotope U²³⁸, act as a fissionable material which can be used in nuclear fission processes instead of using U²³⁵.

Preparation of plutonium follows the following steps:

1. Bombardment by neutron:
₉₂U²³⁸ + ₀n¹——–₉₂U²³⁹

2. Emission of a Beta particle:
₉₂U²³⁹ ——–> ₉₂Np²³⁹ + _-1e⁰

3. Emission of another Beta particle:
₉₂Np²³⁹ ——–> ₉₄Pu²³⁹ + _-1e⁰

Plutonium being chemically different from uranium, it can be separated from U²³⁸ relatively easily. This discovery of plutonium solved the problem of release of nuclear energy through nuclear fission.