As an essential life resource, water faces potential threats from industrial pollution, necessitating the development of effective water treatment techniques. This study explores a bifunctional technology incorporating adsorption and photocatalysis processes. Despite photocatalysis's ability to alter and neutralize dye properties under ultraviolet (UV) exposure, it fails to achieve complete mineralization. Hence, we combined it with biochar-mediated adsorption, which aids in electron-hole separation and dye adsorption on the photocatalyst surface, leveraging the synergistic effects of the composite system. Our research involved preparing and characterizing bark biochar and TiO2 impregnated on cellulose fiber. The characterization was conducted using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The adsorbing performance of these materials was assessed by measuring the removal of methyl orange (MO) (CI 13025) in pure water in the presence of different metal ions. The results showed a significant removal of 100% MO (6 mg/L). This was achieved through a process involving adsorption as a pretreatment, followed by photocatalysis-each step lasting 6 h, under neutral pH conditions using an 80 mg/mL biochar dose. The presence of metal ions, notably CuCl2, improved the oxidative/adsorption performance, potentially facilitating photogenerated charge separation and promoting interface formation between CuCl2 and TiO2. Moreover, the MO decomposition process was analyzed and found to align with the pseudo-first-order model. This study, therefore, provides valuable insights into the combined functioning of biochar-mediated adsorption and photocatalysis, offering a promising solution for efficient wastewater treatment methodologies.