Photocatalytic degradation efficiency of ZnO, GO and PVA nanoadsorbents for crystal violet, methylene blue and trypan blue dyes

•ZnO, GO and PVA nanoadsorbents are studied for crystal violet, methylene blue and trypan blue dyes degradation.•Graphene oxide of 0.3 g degrades efficiently the methylene blue and crystal violet dyes.•Polyvinylalcohol exhibits poor degradation ability compared to zinc oxide and graphene oxide.•Zinc oxide degrades efficiently trypan blue dye compared to methylene blue and crystal violet dyes.