This study confidently explores the production of a-Fe2O3 nanoparticles, Zirconium (Zr)-dopeda-Fe2O3, and Activated Carbon (AC)-Zirconium doped a-Fe2O3 nanocomposites through a precipitation method. The products underwent thorough structural, optical, and morphological analyses. XRD structural analysis revealed that the a-Fe2O3 nanoparticles had a rhombohedral phase. The band gap energies of a-Fe2O3, Zr-doped a-Fe2O3 and AC-Zr-doped a-Fe2O3 are 1.91, 1.86, and 1.73 eV, respectively, indicating the enhanced efficiency of the nanocomposites. The SEM image of AC-Zr-doped a-Fe2O3 nanocomposite showed irregular shapes with aggregated and randomly distributed particles, while the HR-TEM image showed an irregular spherical shape with an average size of similar to 41.91 nm. The photodegradation response of Rhodamine 6G dye under ultraviolet light irradiation was tested for the bare a-Fe2O3, Zr-doped a-Fe2O3, and AC-Zr-doped a-Fe2O3 catalysts. After 90 min of irradiation, the photodegradation ability of the bare a-Fe2O3, Zr-doped a-Fe2O3, and AC-Zr-doped a-Fe2O3 catalysts increased to 65.43%, 66.43%, and 77.98%, respectively, indicating the superior performance of the AC-Zr-doped a-Fe2O3 nanocomposite. The study also confidently investigated the antibacterial effects of the samples on ten bacterial species, revealing that the AC-Zr-doped a-Fe2O3 nanocomposite had the most enhanced inhibitory effects against gram-positive B. subtilis (25.1 +/- 1.16) and S. aureus (21.2 +/- 1.63). These findings demonstrate the great potential of these nanocomposites in various practical applications.