Hydrophobic nanocrystalline glazes based on cassiterite for self-cleaning outdoor power grid insulators

•A novel approach for retarding the pollution of insulators and subsequently the adsorption of water and dry-band arcing and flashover in outdoor insulators has been successfully examined.•Self-cleaning hydrophobic semiconducting glazes were prepared using a base industrial glaze and a semiconducting (95SnO2.xSb2O3.(5-x)NiO) components, in which cassiterite nano needles were crystallized.•The cassiterite crystals caused low surface energy hieracrchical nano-micro protrusions on the glaze surface, which are the two main prerequisite for the lotus effect.•Water contac angles as high as 147˚ were reached.•N-type semiconducting glazes with resistivities as low as 28.35 MΩ.cm, associated with a low band gap of 2.5 eV were obtained.