Excellent photocatalytic performance from NiS decorated TiO2 nanoflowers with exposed {001} facets

•We have designed and fabricated three-dimensional nanoflower-like TiO2 architecture with almost 100% exposed {001} facets.•NiS nanoparticles decorated on n-type TiO2 nanoflowers for forming NiS/TiO2 p-n heterostructures, used as photocatalytic device.•Nanoflower-like NiS/TiO2 p-n heterostructures with exposed {001} facets possesses excellent photocatalytic activity for removal of anionic dyes.