You should avoid anything with talc / talcum.
Most baby powders are made with corn starch. I use baby powder after baths and diaper changes on intact skin, but at the first sign of any kind of rash, discontinue because yeast likes to feed on it and it can lead to a yeast infection.
You can just leave the diaper off for a bit and let the area get some air. You can also just use diaper rash creme as prevention if you want. Every baby has different needs - but yes avoid powders that have talc as an ingredient =)