<p>A sustainable approach to clean water depends on materials that can effectively remove organic contaminants. ZnO/SnS₂/Ti₃C₂ nanocomposites were synthesized by a one-pot hydrothermal method, and the Ti₃C₂ loading was varied from 200 to 800 mg to examine its effect in this work. The addition of Ti₃C₂ MXene was found to improve charge-carrier separation and enhance the visible-light response of the system. These modifications helped assess their influence on the material’s ability to degrade cationic and anionic dye pollutants. The characterization results revealed that ZnO/SnS₂/Ti₃C₂ (800 mg) displayed slower charge-carrier recombination, a narrowed energy band gap of 1.84 eV, and stronger absorption in the visible light range. The experimental findings showed that the ZnO/SnS₂/Ti₃C₂ (800 mg) ternary nanocomposite achieved 98.3% removal of Congo red (anionic) and 99% removal of methylene blue (cationic) from wastewater after about 110 min of UV-A irradiation (λ_max = 352 nm), along with a COD reduction of up to 90%. Radical scavenger tests confirmed that the degradation of Congo red is mainly driven by hydroxyl and superoxide radicals. The ZnO/SnS₂/Ti₃C₂ (800 mg) photocatalyst maintained 76% of its Congo red degradation efficiency after four successive regeneration cycles, demonstrating excellent structural stability and long-term durability. The results confirm that the ZnO/SnS₂/Ti₃C₂ system provides a stable, efficient, and cost-effective strategy for sustainable wastewater treatment.</p> Graphical abstract <p></p>