## 3 Results and Discussion
Activation energies fitted with Equation (1) are 400.4, 29.6 and 29.6 meV for Alq\({}_{3}\) (pure), Alq\({}_{3}\) (Ag NPs) and Alq\({}_{3}\) (Ag NWs), respectively. Compared to Alq\({}_{3}\) (pure), the activation energy of nanostructure-embedded composites shows a dramatic reduction, demonstrating an accelerated thermal exchange between the composites and the surrounding environment. The IPLI enhancement ratio against the temperature plotted in the inset of Figure 6b embodies a similar trend for Alq\({}_{3}\) (Ag NPs) and Alq\({}_{3}\) (Ag NWs). At temperatures below \(\sim\)340 K, the IPLI enhancement ratio exhibits a decreasing behavior, but when the temperature is further increased, it shows an increasing behavior. Generally speaking, the increase in PL enhancement ratio with temperature is due to the increase of plasmonic density of states (DOS) [31; 37; 38]. Therefore, the above phenomenon demonstrates that the DOS decreases first and then increases with increasing temperature. The ratio of Alq\({}_{3}\) (Ag NPs) decreases from 1.21 to 0.64 and then increases to 1.46, and that of Alq\({}_{3}\) (Ag NWs) decreases from 1.57 to 0.57 and then increases to 1.24. It is worth noting that in the temperature range of about 310-380 K, the introduction of Ag nanostructures leads to PL quenching, which may be due to the non-radiative energy transfer from Alq\({}_{3}\) molecules to Ag nanostructures [23], and only in the lower and higher temperature ranges will PL be enhanced. Compared with Ag NPs, Ag NWs can lead to more intense PL enhancement or quenching. More importantly, at the usual operating temperature (below 40 \({}^{\circ}\)C), the DOS increases with the decrease in temperature, which is the main reason for the enhanced SPs coupling. Figure 5: PL spectra of (**a**) Alq\({}_{3}\) (pure), (**b**) Alq\({}_{3}\) (Ag NPs) and (**c**) Alq\({}_{3}\) (Ag NWs) under different temperatures from 298 to 393 K.  
The variations of IPLI with EI are shown in Figure 7a. For all the samples, the IPLI increases monotonously as the EI rises from 0.5 to 19.8 mW/cm\({}^{2}\). The IPLI of Alq\({}_{3}\) (pure) under the highest EI is 49 times that under the lowest EI, indicating that Alq\({}_{3}\) has a very sensitive response to EI. With the incorporation of Ag NPs and Ag NWs, the multiples become 120 and 186, respectively, which are 145% and 280% higher than their non-nanostructured counterparts. Therefore, the response-ability of Alq\({}_{3}\) to EI is improved. To shed further light on the mechanism of PL performance improved by Ag nanostructures, the IPLI is given by:  
\[I_{\rm PL}=k(I_{\rm E})^{\beta} \tag{2}\]  
where \(I_{\rm E}\) is the excitation intensity and \(\beta\) is a coefficient reflecting the coverage of curves with linear behavior. The \(\beta\) values, as extracted from a fit of experimental data with Equation (2), are 0.99, 1.00 and 1.73 for Alq\({}_{3}\) (pure), Alq\({}_{3}\) (Ag NPs) and Alq\({}_{3}\) (Ag NWs), respectively. The Alq\({}_{3}\) (pure) shows only slight sub-linearity due to the thermal accumulation effect caused by the continuous laser. Meanwhile, the Alq\({}_{3}\) (Ag NPs) exhibits a perfect linear trend, indicating that Ag NPs effectively inhibited the thermal accumulation effect and EI-dependent PL sub-linear enhancement. This could also be attributed to the acceleration of the thermal exchange process caused by Ag nanostructures and is consistent with the decrease of \(E_{a}\) mentioned above. Remarkably, Alq\({}_{3}\) (Ag NWs) exhibits super-linear characteristics, indicating the coexistence of radiative and non-radiative recombination [39]. The IPLI enhancement ratio is dependent on the EI, as seen in Figure 7b. When the EI is lower than 1.7 mW/cm\({}^{2}\), the enhancement ratio of Alq\({}_{3}\) (Ag NPs) shows a rapid increase trend upon the increase in EI, and then gradually slows down with the further increase  
Figure 6: (**a**) Temperature-dependent IPLI of Alq (pure), Alq\({}_{3}\) (Ag NPs) and Alq\({}_{3}\) (Ag NWs); (**b**) IPLI enhancement ratio as a function of temperature.