I think all African countries charge some kind of tax - you would need to look at countries, states or principalities like the below
Bahamas
The British Virgin Islands
Brunei
Monaco
Vanuatu
Probably a few more, the above where off the top off my head (could be wrong so double check)
You can get a free consultancy with an off shore tax adviser, normally done over the phone and they will go through how it how it works