## 3 Results and Discussion
### Photocatalytic Evaluation
Additional photocatalytic tests were conducted to assess the impact of the Ag\({}^{+}\) concentration (10\({}^{-4}\)-10\({}^{-2}\)M range) on the co-catalytic modification of TP2 and TP4 films during the photocatalytic decolorization process of dyes. The activity of silver photo-fixed samples surpasses that of TP2 and TP4 films, validated by the rate constants. Silver photo-fixation significantly enhances the efficacy of both TiO\({}_{2}\) films, leading to an additional increase in rate constants, observed in both the TP2 and TP4 samples. Our tests reveal that the presence of silver enhances the degradation of dyes under light exposure. Light absorption by TiO\({}_{2}\) excites electrons from the valence band to the conduction band. Co-catalytic modification with silver enhances TiO\({}_{2}\) activity for MG and MB photodecomposition by trapping electrons from the conduction band onto Ag [17], which produce superoxide radicals [36]. Simultaneously, photoinduced holes in the TiO\({}_{2}\) valence band react with surface-attached H\({}_{2}\)O or OH\({}^{-}\) to produce OH\({}^{\bullet}\) radicals, potent oxidants crucial for decomposing organic pollutants. Utilizing silver photo-fixed TiO\({}_{2}\) improves photocatalytic activity using by enhancing photo-induced charge carrier separation and delaying electron-hole pair recombination [30]. Silver acts as an electron trap, absorbing e\({}^{\prime}\) from the TiO\({}_{2}\) conduction band and transferring them to O\({}_{2}\) to form superoxide radicals. Water molecules react with the remaining photogenerated holes on TiO\({}_{2}\) to produce hydroxyl radicals, facilitating the effective degradation of dyes dissolved in distilled water. Figure 8 illustrates a potential mechanism for degrading organic dyes using pure and silver photo-fixed films. Figure 7: Kinetics of removal of methylene blue under UV (**a**,**b**) and visible (**c**,**d**) light. Due to the creation of stable intermediates by the reaction of OH\({}^{\bullet}\) with triarylmethane dye (C=C bond), the pure and silver co-catalytically modified films exhibited a faster degradation of MG compared to that of MB. The literature [37; 38] describes the processes by which OH\({}^{\bullet}\) causes degradation of Methylene blue and Malachite green, a process in which, according to [PERSON] et al. [37], the OH\({}^{\bullet}\) first cleaves the S+=C bond, which causes the central heterocyclic part to undergo a ring-opening reaction, in the case of MB. Similarly, [PERSON] et al. [38] revealed that for the MG case, the first stage of dye decomposition involves a radical attack on the C atom (central), changing it into a Malachite green carbinol base and causing the pollutant to degrade once more. After considering the aforementioned logic, it can be said that the OH\({}^{\bullet}\)-facilitated attack on the S atom may be the cause of the Malachite green's quicker degradation observed in this investigation, attributed to an increase in the electron density. Sustaining consistently high photocatalytic efficiency throughout the repeated usage of a photocatalyst is crucial for its applicability in environmental applications. Therefore, photocatalytic experiments are also conducted to test the cycling stability of the two best catalysts (TP4 and Ag, 10\({}^{-2}\)/TP4) for the degrading MG and MB under UV illumination. Figure 9 illustrates the findings of an investigation into powder regeneration and repurposing, indicating a progressive decline in the catalytic quality with each cycle. After three cycles, both dyes' photocatalytic decomposition decreased by approximately 2% for each of the TP4 and Ag, 10\({}^{-2}\)/TP4 catalysts. Nonetheless, the co-catalytically modified nanostructures continued to have high photo-catalytic activity after three cycles of experiments. Figure 8: The potential mechanism of photocatalysis. The presence of silver in the two dye solutions before, during, and after photocatalysis was tested to check for co-catalyst leeching from the catalysts.