Hydrothermally grown and self-assembled modified titanium and nickel oxide composite nanosheets on Nitinol-based fibers for efficient solid phase microextraction

•The TiO2/NiOCNSs was obtained by hydrothermal treatment of Nitinol wires.•Unique TiO2/NiOCNSs have double-faced open access sites with large surface area.•A novel TiO2/NiOCNSs-Ph fiber coating was achieved by SAM process.•The fiber has high extraction capability and better selectivity for UV filters.•The proposed method was applied to UV filters in environmental water samples.