Advances in Graphene Oxide-Based Composites and Membranes: Structural Engineering, Multifunctional Performance, and Emerging Applications

Graphene oxide (GO), with its high surface area, tunable chemistry, and exceptional mechanical, thermal, and electrical properties, is rapidly advancing as a transformative material in both composite engineering and membrane technology. In composite systems, GO serves as a multifunctional reinforcement, significantly improving strength, stiffness, thermal stability, and conductivity when integrated into polymeric, ceramic, or metallic matrices. These enhancements are enabling high-performance solutions across electronics, aerospace, automotive, and construction sectors, where lightweight yet durable materials are in demand. In addition, GO-based membranes are revolutionizing water purification, desalination, and other high-end separation technologies. The layered structure, adjustable interlayer spacing, and abundant oxygen-containing functional groups of GO allow precise control over permeability and selectivity, enabling efficient transport of desired molecules while blocking contaminants. Tailoring GO morphology and surface chemistry offers a pathway to optimized membrane performance for both industrial and environmental applications. This paper gives a comprehensive overview of the latest developments in GO-based composites and membranes, highlighting the interplay between structure, morphology, and functionality. Future research directions toward scalable fabrication, performance optimization, and integration into sustainable technologies are discussed, underscoring GO’s pivotal role in shaping next-generation advanced materials.