•Layered α-ZrP is assembled with BNMA by electrostatic LBL technique.•(BNMA/α-ZrP)n films are ordered and in cycles.•The fluorescence lifetimes of multilayer films were prolonged up to 16-fold.•The reasons are the isolation effect and hydrogen ion migration between layers.In the present work, photoactive cation N, N′-Dimenthyl-9, 9’-bisacridinium nitrate (BNMA) was assembled with exfoliated layered α-zirconium phosphate (α-ZrP) via an electrostatic layer-by-layer (LBL) assembly method. As a result, the luminescent films which were well-aligned and periodical had been successfully fabricated. Surprisingly, the lifetimes of (BNMA/ZrP)n were found to be prolonged by 16-fold for the first time, due to the isolation effect of inorganic nanosheets and hydrogen ion migration between the interlayers. Therefore, it is testified that α-ZrP can be used as the laminate and has remarkable influences on enhancing the lifetimes of chromophores. We expect that this new discovered effect can enable α-ZrP a kind of new potential material to develop novel light-emitting materials and optical devices.

•Transition metal-bearing layered double hydroxides provide magnetic field (MF).•A novel electronic microenvironment (EME) is successfully designed.•The EME is assembled by oppositely-charged inorganic nanosheets.•Chromophores are successfully designed in EME and MF between the interlayer.•Lifetimes of chromophores with EME and MF are highly prolonged.In this report, luminescent multilayer thin films (MTFs) based on oppositely-charged montmorillonite (MMT) and transition metal-bearing layered double hydroxides (LDHs) nanosheets were fabricated via a layer-by-layer assembly method. Oppositely-charged inorganic nanosheets can be expected to assemble an electronic microenvironment (EME), and transition metal-bearing LDHs nanosheets can offer an additional magnetic field (MF) for the chromophores at the same time. Surprisingly, the luminescent lifetimes of MTFs with EME and MF are significantly prolonged compared with that of the pristine chromophores, even much longer than those of MTFs without oppositely-charged and magnetic architecture. Therefore, it is highly expected that the EME and MF formed by oppositely-charged and transition metal-bearing inorganic nanosheets have remarkable influence on enhancing the luminescent lifetimes of chromophores, which suggest a new potential way to manipulate, control and develop the novel light-emitting materials and optical devices at molecular level.

In this report, luminescent multilayer thin films (MTFs) based on functional molecules intercalated into layered double hydroxides (LDHs) and montmorillonite (MMT) nanosheets were fabricated by layer-by-layer assembly method (LBL method). Exfoliated LDHs and MMT nanosheets with opposite charges can be expected to provide an electronic microenvironment (EME) for chromophores, which are not found in previous literatures, and to offer the inorganic rigid building blocks at the same time. Surprisingly, the lifetimes of MTFs with EME's architecture are significantly prolonged, compared with that of the pristine powder, even considerably longer than those of the MTFs without EME's architecture. Therefore, it is highly expected that the EME formed by oppositely-charged inorganic nanosheets has remarkable influence on enhancing the lifetimes of chromophores, which suggests a new potential method to develop novel light-emitting materials and optical devices.

•Phase equilibrium of the system K2CO3-Na2CO3-H2O at (323.15, 343.15 and 363.15) K.•The salting-out effect was enhanced with the increasing of temperature.•The densities of liquid phase were investigated and compared with calculated value.In order to provide a theoretical basis and fundamental data for industrial utilization of insoluble potassium rocks to produce potassium salts, the phase equilibrium of the ternary system K2CO3-Na2CO3-H2O at 323.15 K, 343.15 K and 363.15 K was determined using the isothermal dissolution equilibrium method. According to the experimental results of salt solubility, the phase diagrams were constructed and the crystallization zones are discussed in detail. All of the solubility isotherms at 323.15 K, 343.15 K and 363.15 K consist of two invariant points, three univariant curves and three crystallization fields corresponding to Na2CO3·H2O, K2CO3·Na2CO3 and K2CO3·1.5H2O, respectively. The densities of the liquid phase of the ternary systems were investigated as well.