## 1 Introduction  
The high activity of photocatalysts has rendered them attractive materials for pollutant removal and recycling waste substances in the environment [1; 2; 3; 4]. Despite the utilization of chemical precipitation, biological, and physical methods in wastewater treatment, they suffer from drawbacks, e.g., high costs and energy consumption, secondary waste generation, and prolonged treatment durations [5; 6]. Consequently, alternative strategies must be devised to circumvent these limitations. Heterogeneous photocatalysis emerges as a viable solution due to its high effectiveness at mild conditions, governed by the production of reactive oxidative species (OH\({}^{\bullet}\)) [7]. TiO\({}_{2}\) stands out as a significant photocatalyst among various semiconductors owing to its exceptional activity and physicochemical properties crucial for pollutant remediation [8; 9] but suffers from a general low quantum yield. Doping TiO\({}_{2}\) with non-metals, metals, and transition metals has been a strategy to enhance its photocatalytic performance [10; 11; 12]. Silver, in particular, shows promise in augmenting the physicochemical properties of TiO\({}_{2}\), offering potential applications in purification, antibacterial properties, and self-cleaning [13; 14; 15]. [PERSON] et al. demonstrated that Ag-doped TiO\({}_{2}\) exhibits superior physicochemical properties compared to those of TiO\({}_{2}\)[16]. Their findings reveal that Ag doping enhances the material's ability to absorb visible light, resulting in a narrower bandgap, reduced total surface area, and Ag surface plasmon resonance. Additionally, [PERSON] et al. have explored Ag-TiO\({}_{2}\) photocatalysts for photocatalytic removal [17].  
On the other hand, considerable effort has been dedicated to developing composite photocatalysts with surfactant assistance by employing structure modifiers to enhance their physicochemical and photocatalytic characteristics [18]. Surfactants such as polyvinylpyrrolidone, polyethylene glycol, and cetyltrimethylammonium bromide are commonly used in the synthesis of TiO\({}_{2}\) composites [19; 20; 21; 22]. Among these, the non-ionic surfactant PEG is deemed an appropriate structure-directing agent due to its high water solubility, stability, non-toxicity, and thermal breakdown upon calcination [23; 24]. PEG has been extensively researched for creating dye-sensitized TiO\({}_{2}\) nanoparticles to enhance stability, durability, and charge transfer during the energy production process [25; 26]. [PERSON] et al. [25] and [PERSON] et al. [27] demonstrated that the morphology, crystalline size, and grain growth of PEG/TiO\({}_{2}\) photocatalysts are all highly influenced by the molecular weight of PEG, illustrating how the optimal molecular chain length could be of nanoparticle size and growth rate. Thus, incorporating PEG with optimum molecular weights to modify the unique Ag/TiO\({}_{2}\) photocatalyst may improve its morphology, crystalline structure, and catalytic activity under light irradiation.  
In the current study, TiO\({}_{2}\) powder films are prepared using PEG with different molecular masses. The relationship between the physicochemical properties and the photocatalytic efficiency of the samples is evaluated. Our work focuses on: (i) the effects of PEG molecular mass on the structural and photocatalytic properties of TiO\({}_{2}\) powder films for accelerated organic dye degradation; (ii) the influence of silver ion concentrations, photo-fixed onto the film surface; (iii) the difference in the reactivity between the investigated pollutants; (iv) the photostability of TP4 and Ag, 10\({}^{-2}\)/TP4 films after three cycle of photocatalysis; and (v) atomic-absorption determination of residual noble metal in dye solution.