Deodorant kills bacteria that causes bad smells, and masks the smell of sweat. Antiperspirant reduces the amount of sweat produced by actually blocking ducts. So deodorants will make you smell better,

Smelly armpits (also known as body odor) is not caused by perspiration. The main components of sweat are water and salt. In fact, it is caused by bacteria that are attracted to the place where you sweat

Most underarm antiperspirants contain as the active factor, Aluminium Chlorohydrate, as you'll likely take into account there has been controversy about Aluminium, since the 1950’s while it became a popular