Efficient Pb(II) adsorption in aqueous solution by hierarchical 3D/2D TiO2/CNNS nanocomposite

•Hierarchical 3D/2D TiO2/CNNS nanocomposite was ultrasonically constructed by means of the precursors TiO2 and g-C3N4 nanosheets.•The produced nanostructures showed extraordinarily selective adsorption towards Pb (II) metal ions through strong electrostatic attraction.•The obtained batch mode adsorption measurements reveal a high removal efficiency of give 378 mg.g−1 in a very short period of time of 7 min.•This hierarchical TiO2/CNNS composite is a promising material for removing heavy metals in aqueous solution. A multifunctional nanomaterial for contaminants’ removal and solar fuel production is designed, for solving environmental and energy problems. In this research, hierarchical three-dimensional (3D)TiO2 doped with porous graphite-like two-dimensional (2D) carbon nitride (g-C3N4) nanosheets (TiO2/CNNS) composite was fabricated by solid interfacial reaction through a facile acid hydrothermal route. Interestingly, the produced catalyst showed extraordinarily selective adsorption towards Pb (II) metal ions through strong electrostatic attraction mainly due to the enlarged surface areas and pore volume, besides increased adsorption/active sites. The obtained batch mode adsorption measurements reveal a high removal efficiency of give 378 mg.g−1 in a very short period of time of 7 min. This study highlights the importance of designing 3D/2D multifunctional g-C3N4-based photocatalysts for environmental heavy metals decontamination.