The increasing concerns over environmental pollution and climate change have driven global efforts to develop sustainable detection and remediation techniques. Carbon-based materials are essential in tackling these challenges due to their distinctive characteristics, including high surface area, adjustable porosity, electrical conductivity, and chemical stability. This chapter explores real-world case studies demonstrating the application of carbon-based materials, both bulk and nano-carbon, in addressing environmental challenges. Bulk carbon materials, including activated carbon, biochar, carbon black, and carbon fiber, find extensive application in water purification, air filtration, soil remediation, and photocatalysis, showcasing their cost-effectiveness in effectively removing various contaminants from air, water, and soil. Meanwhile, nano-carbon materials, including carbon nanotubes, graphene, activated carbon nanoparticles, carbon quantum dots, and nanodiamonds, offer enhanced capabilities in sensing hazardous pollutants, adsorbing toxic gases, removing heavy metals, and degrading chemical and biological contaminants. Carbon-based sensors, known for their high sensitivity and selectivity, are increasingly used in real-time monitoring of pollutants like heavy metals, volatile organic compounds, and greenhouse gases. Case studies illustrate these sensors’ advanced solutions for early detection and rapid response. Innovative remediation technologies that leverage carbon materials’ adsorption, catalysis, and filtration properties are also explored. Examples from water treatment plants, air purification systems, and soil remediation projects emphasize their cost-effectiveness, recyclability, and scalability. The effectiveness and sustainability of these approaches are emphasized concerning the circular economy by producing carbon materials from renewable resources like agricultural waste and biomass. It highlights the growing significance of low-cost, eco-friendly carbon sources in environmental applications. Furthermore, it discusses challenges, including the regeneration of spent materials, large-scale implementation, and the need for environmental impact assessments. A comprehensive analysis of bulk and nano-carbon materials highlights their relative strengths, challenges, and future potential for advancing sustainable environmental detection and remediation.