An advanced three-dimensional printing process for producing the Ag/AgCl/TiO2-coupled photocatalyst was developed and tested for its stability and degradability in relation to azo dye (Orange II) and bacteria (Escherichia coli). The TiO2 structure is produced through fused filament fabrication (FFF) with filaments of thermoplastic material, which is composed of TiO2 anatase nanoparticles, high density polyethylene (HDPE), stearic acid, wax, and plasticizer. The TiO2 structure is then solvent degreased, thermal degreased, and sintered to become a fundamental structure to couple the AgCl particles through an ion exchange process. Following the photoreduction of UV radiation, a Ag/AgCl/TiO2-coupled photocatalyst is formed. In our experiments, this photocatalyst effectively degraded Orange II dye and sterilized E. coli. The degradation of Orange II dye and E. coli was performed under visible and ultraviolet light irradiation. The degradation kinetics of Orange II dye was a first-order reaction, with the degradability (94%) persisting for five cycles. The sterilization of E. coli was accomplished within 120 min, and the degradation kinetics were characteristic of a hyperbolic reaction. The photocatalytic module fabricated through FFF not only exhibited the ability to degrade contaminants in water but also exhibited durability and reliability after repeated use.