Polymeric carbon nitrides/3D honeycomb poly(ionic liquid)s photoreactor with improved photo-electric property for efficient wastewater treatment

•A sunlight driven photoreactor is prepared by swelling poly(ionic liquid)s with polymeric carbon nitrides.•The poly(ionic liquid)s can enhance the separation of photogenerated electron-hole pairs of polymeric carbon nitrides.•The 3D honeycomb network structure of photoreactor increases the contact between the reaction substrates and the active sites.