## 3 Results  
Figure 2a shows the UV-vis absorption spectra and photoluminescence spectra of MA(\(n\))-films with varying numbers of layers (\(n\) = 4, 8, 12, 16, 24, 32), and the inset of left figure indicates the intensities of absorption peaks increase linearly at 293.5 nm and 452.5 nm when the layers grow, displaying a well-organized growth in assembly process of those thin films. Under 375 nm excitation, these thin films give a green emission band peak at 572.0 nm (Figure 2b). Meanwhile, the intensities of fluorescence peaks also increase gradually as the deposition cycles increase, which shows that the films grow stepwise. Moreover, as shown in Figure 2c about small angle XRD peaks, the intensities of multilayer films increase with the deposition cycles, and the films have well-organized structure in the vertical direction with a period of ca. 4.18 nm. At the same time, MA(\(n\))-films are extremely regular and smooth in the SEM image (Figure 2d). Surprisingly, the luminescent lifetimes of MA(\(n\))-films range from 1.32 ns to 1.41 ns, nearly 2.2 times as long as poly [5-methoxy-2-(3-sulfopropyl)-1,4-phenylenevinylene] (APPV) solution (0.6 ns), about 1.0 times longer than those of (LDHs/APPV)\({}_{n}\)' (marked as LA(\(n\))-films, 0.66-0.81 ns) [15]. Negative-charged MMT nanosheets can provide isolation effect and electrostatic repulsion for the anionic APPV, thus leading to the APPV stacking more orderly and suppressing the formation of aggregates. In order to confirm EME's effect, referred to in our present work on the anionic chromophores, MALA(\(n\))-films were fabricated via a similar method to the present work [15]. Figure 3a shows the UV-vis absorption spectra of MALA(\(n\))-films, which grow in a stable step with the layer number. The peak of absorption at 293.5 nm and 452.5 nm are absorption of phenylene ring and \(\pi\)-\(\pi^{\ast}\) transition of APPV. The emission band peak is seen at 578.0 nm as yellow in color, and the emission intensity also increases consistently with the layer number (Figure 3b). Compared to the MA(\(n\))-films, the luminescent peak occurs during a red-shift. When introducing the rigid oppositely-charged inorganic nanosheets, isolation effect and EME can affect either intermolecular interaction or entangled main-chain. Firstly, they can have an impact on intramolecular phenyl-phenyl stack structure, which give rise to emerge a decrease in electronic \(\pi^{\ast}\)-\(\pi\) transition energy (red shift in luminescent band) and the increase in oscillator strength. Secondly, they can also make the entangled main-chain loosen and flatten. As a result, energy-trapping sites with lower electronic transition energies are more easily formed. Moreover, small angle XRD and SEM images show that multilayer films are regular and uniform with a period of ca. 6.74 nm (Figure 3c,d). Importantly, the lifetimes of MALA(\(n\))-films (1.47-1.59 ns) are about 1.50 times longer than APPV solution (0.60 ns), are also prolonged to nearly 2.0-fold combined with LA(\(n\))-films' (0.66-0.81 ns), and with an increasing than MA(\(n\))-films (1.32-1.41 ns). The dominant factor is that LDHs and MMT inorganic nanosheets can assemble EME in this nano-architecture, which can affect the vibration of backbone and extend the relaxation time, finally prolonging lifetimes [19; 20]. Above all, EME is helpful to improve photoemission behaviors of multilayer films. When introducing MgAl-LDHs and MMT nanosheets into the nano-system, lifetimes of chromophores can be prolonged by a large margin. The quantum yield (QY) of MALA(\(n\))-films (\(n\) = 8, 16, 24) are 0.001363%, 0.001319%, 0.001598%, and the QY of MA(\(n\))-films (\(n\) = 8, 16, 24) are 0.001990%, 0.002032%, 0.002143%. The first reason for the so low QY values is the imbalance of hole/electron injection and transport because the emissive polymer conduct holes are used in preference to electrons [21; 22]. Due to the easily trapped excitons and constant nonradiative decay, there is the presence of defects in the polymer, so this is the second reason [23; 24].