Co3O4 nanoparticles assembled coatings synthesized by different techniques for photo-degradation of methylene blue dye

► Co3O4 NPs assembled coatings synthesized by PLD, EBD, sol-gel, and electroless methods. ► Co3O4 NPs synthesized by PLD showed the best photo-degradation activity for MB dye. ► Morphological, structural, and optical properties of NPs (PLD) suit perfectly for catalysis.