<p>The need for advanced water pollution monitoring and remediation methods has increased due to rapid development and human activity. This review emphasizes ‘electroactive nanomaterials’ importance in sustainable solutions, detailing their use in environmental water monitoring and treatment. The key materials discussed include: activated carbon, biochar-derived nanomaterials, graphene, graphene quantum dots, and metal-organic frameworks. These materials display outstanding electrochemical behaviour, tunable properties, and environmental adaptability. These nanomaterials show significant potential for real-time detection of various contaminants, making them ideal for future water monitoring. The discussion also covers potential future research, concentrating on scalable sensor technology, biocompatibility and material engineering for practical environmental applications.</p>