Water contamination is a drastic worldwide issue menacing the whole biosphere and disturbing people lives as long as human health is strongly depended on the drinkable form of this liquid. It becomes a growing concern when we know the major cause of many diseases around the world is dirty water. Ag/AgCl decorated tube-like g- C3N4 (T-C3N4) nanostructures were successfully fabricated by thermal pyrolysis and coprecipitation methods. The photocatalysts were comprehensively characterized through a multi-technique approach including XRD, DRS, SEM, EDX, TEM, FTIR, BET-BJH, PL, and DLS physicochemical techniques. The photoactivity of the structures was evaluated for Acid Blue 92 (AB92), a dye compound, removal and GBM (U87) cancer cells treatment under visible light. MTT viability assay, ROS assay, fluorescent images, flocytometry (Cell Cycle assay) and mitochondria membrane potential (ΔΨm) techniques were also served to illustrate the mechanism of tumor cells removal. From our results, ionic liquid-mediated growth of Ag/AgCl nanoparticles on the surface improved the photoactivity and anticancer properties of tubular g-C3N4 significantly.