泛泛 most often shows up in fixed phrases:
泛泛之交 (fànfàn zhī jiāo, nodding acquaintance),
泛泛而谈 (fànfàn ér tán, to speak in general terms / superficially). Standalone modifying a noun (
泛泛的介绍) is also fine. Always carries a slightly negative "not deep enough" connotation.