You Do Need power plug adapter while traveling from Dominican Republic to Sierra Leone.

Here is Why You Need An Adapter

The outlet and plug type used in Sierra Leone are D and G and in Dominican Republic are A, B and C. This is how they look like.

Dominican Republic

In Dominican Republic, outlets of type A, B and C are in use.

Type A

Type B

Type C

Sierra Leone

In Sierra Leone, outlets of type D and G are in use.

Type D

Type G