Synthesis and layer-by-layer self-assembly of titania nanosheets controllably doped with binary transition metal ions

摘要

Here, we describe the synthesis of novel titania nanosheets controllably doped with binary transition metal ions and their layer-by-layer self-assembly. The tailored Mn and Fe doping in exfoliated Ti_()0.6Mn_(X/2)Fe_((0.8-X)/2)O_2 (x = 0.0-0.4) nanosheets is achieved by systematically changing the molar ratio of Mn/Fe in K_(0.8)Ti_(1.2)Mn_xFe_(0.8-x)O_4 using a codoping strategy. The protonated layered crystals exhibit a delaminated behavior in the tetrabutylammonium hydroxide solution and are exfoliated into colloidal single sheets, which are characterized by a large lateral size and a thickness in molecular dimension. The resulted nanosheets are able to be layer-by-layer deposited with oppositely charged polymers into a composite organic/inorganic system.