One-step synthesis of dandelion-like lanthanum titanate nanostructures for enhanced photocatalytic performance

Abstract

Abstract: The rational design of nanomaterials with distinct exposed facets is of great importance for improving the physicochemical properties of these materials and for the study of structure–activity relationships. This work describes the first synthesis of lanthanum titanate (La2Ti2O7, LTO) with dandelion-like nanostructures via the molten salt method. The lowest synthesis temperature of 700 °C is at least 200 °C lower than that required by other methods. The dandelion structure consists of well-crystallized LTO nanorods (NRs) with sizes of less than 100 nm in the radial direction and 300–500 nm in the axial direction, which is different from the widely accepted two-dimensional form. LaOCl microplates were formed as an intermediate substrate for LTO NR growth outwards to the basal surfaces of the LaOCl crystallites. DFT calculation results showed that the strong LiCl adsorption on the (100) surface led to distinct growth of the (100) and (020) planes, thus promoting the rod-like growth of LTO along the [010] axis. In addition, the photocatalytic performance of as-prepared LTO was evaluated by determining the degradation of rhodamine B. The results suggested that the as-prepared LTO could markedly enhance the photocatalytic activity as a result of the surface heterojunction of coexposed {100} and {002} facets in LTO NRs.