not unless you have a massive tank for your betta
common pleco's get huge, and most people don't have a tank actually big enough for them.
how big is the betta's tank?
it's not always necessary to have something to "eat algae" the type of algae that grows in a tank is often not the type the fish will eat. and even if it is, there isn't enough of it to completely provide for them, you'll have to feed algae wafers, or vegetables also.
if you just like the algae eater thing, you could try ottocinclus. but they can be tough to keep alive, especially in a small tank.
if you're looking for a "bottom feeder" you could try pygmy cories (only get to 1"), shrimp, snails.