<p>The increasing prevalence of environmental pollutants has driven the need for efficient and versatile treatment methods. This review provides a comprehensive overview of copper-based photocatalysts for pollutant degradation, with a focus on their potential to address various organic pollutants. Copper oxide nanoparticles, or CuO NPs, have emerged as promising materials due to their ability to utilize light energy for the photocatalytic breakdown of persistent contaminants, such as dyes, pesticides, and pharmaceuticals. Advancements in the green synthesis of CuO NPs are discussed, with an emphasis on eco-friendly and cost-effective precursors, including recycled materials, which contribute to both improved photocatalytic performance and sustainability. The versatility of copper-based photocatalysts in degrading a wide range of pollutants is explored, highlighting their potential for diverse environmental applications. The review also examines the challenges and future directions in the field, emphasizing the need for continued research to optimize these materials for more effective and sustainable wastewater treatment technologies.</p>