<p>In recent decades, the focus on building a sustainable living environment has shifted to two key goals: providing clean water and increasing the use of renewable energy. Photocatalytic processes are a possible alternative since photocatalysts are extremely successful at water purification and producing renewable energy sources. This study focuses on developing a sustainable photocatalyst for environmental remediation by synthesizing copper-doped Co₃O₄ nanoparticles on MoS₂ nanosheets using co-precipitation method. For the first time, we report a visible-light-driven photocatalyst of Cu–Co₃O₄/MoS₂ nanocomposite for photo-Fenton-like degradation activity. The structural, morphological, surface chemical, and optical properties of the samples were deeply analyzed. The results show a significant improvement in photocatalytic performance, achieving a <b>98%</b> degradation of methylene blue dye under visible light in <b>60 minutes.</b> The enhanced efficiency is attributed to the synergistic effect of Cu–Co₃O₄ and MoS₂, which improves charge separation, increases active sites, and facilitates electron transfer. This makes the nanocomposite a promising solution for sustainable environmental remediation.</p> Graphical Abstract <p></p>