Natural sustainable coatings for marine applications: advances, challenges, and future perspectives

Abstract The increasing environmental concerns associated with conventional marine coatings have driven significant research interest toward the development of natural sustainable coatings as eco-friendly alternatives. This review addresses the urgent need for greener solutions by systematically analyzing recent advancements in bio-based marine coatings, focusing on materials derived from natural polymers, plant-based oils, marine biopolymers, and bioinspired functional additives. Through a critical evaluation of over 100 articles retrieved from the Scopus database (2018–2025), key sustainable materials such as chitosan, alginate, barnacle cement proteins, and plant-derived surfactants are identified, with detailed discussion of their antifouling and anticorrosion mechanisms. The review reveals that while these materials show great promise, significant challenges remain related to durability, scalability, and regulatory acceptance. Future trends point toward the integration of nanotechnology, smart responsive coatings, and bioinspired antifouling strategies to overcome current limitations. Based on the synthesis of recent findings, this study recommends a multidisciplinary approach combining material innovation, biotechnology, and adaptive design to accelerate the industrial adoption of natural sustainable coatings, thereby promoting marine sustainability and reducing ecological footprints. This review provides a clear roadmap for future research and development in the field, guiding both academic investigation and industrial application.