An inorganic nanohybrid with high specific surface area: TiO ₂-pillared MoS₂

A novel lamellar inorganic-inorganic nanohybrid (TiO₂-pillared MoS₂) has been successfully synthesized by an exfoliation- reassembling method. According to the X-ray diffraction and cross-sectional transmission electron microscopy analyses, quantum-sized TiO₂ nanoparticles with a diameter of 1 nm are homogeneously distributed in the interlayer space of a two-dimensional MoS₂ lattice. Such structural regularity of pillars results in a remarkable enhancement of porosity, as confirmed by nitrogen adsorption-desorption isotherms. The Langmuir specific surface area (186 m² g^-1) of the TiO₂-pillared MoS₂ has been determined to be remarkably larger than that (12 m ² g^-1) of the restacked MoS₂. It is, therefore, evident that adequate intercalation of TiO₂ nanoparticles into a MoS₂ lattice gives rise to a highly porous structure. Ti K-edge extended X-ray absorption fine structure (EXAFS) analyses also indicate that the anatase nanopillars are stabilized in the interlayer space of MoS₂ without any significant agglomeration. From Mo K-edge EXAFS studies, it has been found that the highly distorted octahedral structure of the host lattice in the as-prepared nanohybrid changes into a thermodynamically stable trigonal prismatic one upon heat treatment.