Assembly of luminescent ordered multilayer thin-films based on oppositely-charged MMT and magnetic NiFe-LDHs nanosheets with ultra-long lifetimes

In this present report, luminescent ordered multilayer thin films (OMFs) based on oppositely-charged inorganic nanosheets and the different oppositely-charged chromophores were fabricated via layer-by-layer assembly method. Exfoliated layered double hydroxides (LDHs) and montmorillonite (MMT) nanosheets with opposite charges can be expected to provide a pseudo electronic microenvironment (PEM) which has not been declared in previous literatures, and transition metal-bearing LDHs nanosheets can offer an additional ferromagnetic effect (FME) for the chromophores at the same time. Surprisingly, the luminescent lifetimes of those OMFs with PEM and FME are significantly prolonged compared with that of the pristine chromophores, even much longer than those of OMFs without oppositely-charged and ferromagnetic architecture. Therefore, it is highly expected that the PEM and FME formed by oppositely-charged and transition metal-bearing inorganic nanosheets have remarkable influence on obtaining better optical property, which suggests a new potential way to manipulate, control and develop the novel light-emitting materials and optical devices.