Copper (Cu) is an effective antimicrobial material; however, its activity is inhibited by oxidation. Visible light-driven photocatalysis prevents Cu oxidation and improves its antimicrobial activity and stability. In this study, the superior microbicidal activity of WO₃ nanoparticles with Cu ions under visible light illumination (Cu/WO₃/vis) was investigated compared to other visible light-driven photocatalysts. For these purposes, WO₃, nitrogen-doped TiO₂ (N-TiO₂), BiVO₄, and CdS were prepared and characterized, and their efficacy in microbial inactivation was investigated. Furthermore, crystal facet engineering was employed to enhance the disinfection efficiency of WO₃. In this study, three WO₃ nanosheets with small, medium, and large ratios of {002} facets were synthesized. These materials were evaluated for the microbial inactivation with Cu ions under visible light illumination.  To gain insight into the behaviors of Cu ions and microbicidal mechanism in the Cu/{002}WO₃/vis system, the generation of Cu(I) and Cu(III) species, and the effects of different additives and dissolved oxygen on the microbial inactivation were investigated. Additionally, the applicability of the Cu/{002}WO₃/vis system was tested through repeated inactivation experiments and in different water matrices