The increasing presence of hazardous compounds in water and air, primarily due to industrial waste, poses a significant threat to environmental sustainability and public health. Advanced photocatalysis employing graphene nanomaterials offers a promising solution to mitigate this issue. This chapter explores the pivotal role of graphene-based nanomaterials (GBNMs) as sustainable photocatalysts for degrading hazardous compounds. By leveraging graphene’s exceptional electronic, optical, and surface properties, the efficiency of photocatalytic processes can be significantly enhanced. The chapter analyzes the fabrication techniques of graphene-based nanocomposites, emphasizing their structural characteristics and the mechanisms driving photocatalysis under light irradiation. It further investigates the degradation pathways for common hazardous pollutants, including dyes, pharmaceuticals, and pesticides. The discussion extends to the environmental benefits of these materials, addressing critical challenges associated with scaling up their application and outlining future research directions to bridge the gap between laboratory studies and practical implementations. This chapter highlights the promise of GBNMs to promote cleaner and greener technologies, underscoring their transformative role in advancing sustainable environmental solutions.