Batman often has a place of sympathy for certain villains, as he knows that they weren't born this way, but rather made into what they are now. Clayface has often been one of those villains.
In fact, during The Batman, it was Bruce's best friend, Ethan Bennet, that was turned into the first Clayface. Eventually, he was able to cure him, and Bennett even helped him catch the new Clayface in order to do so.
In the comics, Batman has often tried to cure Clayface, and in the new Detective Comics under the DC Rebirth banner, Batman is actually having Clayface on his team to fight a new threat. With the promise of curing him once he's done.