<p>The global transition towards clean energy requires the development of sustainable and scalable alternatives to fossil fuels, with green hydrogen emerging as a key solution. While nanocatalysts have shown significant potential in hydrogen production, obstacles remain, particularly in advancing efficient and cost-effective catalysts derived from waste materials. The existing body of literature lacks comprehensive assessments of the environmental and economic implications of these catalysts, thereby constraining their wider applicability. This study addresses this deficiency by consolidating recent advancements in converting industrial, agricultural, and municipal waste into high-performance nanocatalysts for hydrogen generation. In comparison to conventional methodologies, these waste-derived catalysts have demonstrated hydrogen yields that are up to 30% higher and have significantly diminished carbon footprints, as corroborated by life cycle assessment (LCA) studies. This study also investigates practical applications, policy frameworks, and sustainability metrics to furnish a comprehensive understanding of their potential. Ultimately, it delineates critical technical and economic challenges, advocating for interdisciplinary research to expedite the implementation of waste-based catalytic technologies. This study highlights the transformative potential of nanocatalysis in green hydrogen systems and underscores its alignment with objectives related to the circular economy and climate initiatives.</p>