Abstract:Metal corrosion occurs absolutely in aggressive media, which may cause serious consequences. Therefore, it is very important and significant to realize metal corrosion inhibition. As compared with chemically synthesized organic corrosion inhibitors, plant extract-based inhibitors have many unique advantages, such as low cost, environment-friendly, renewable and sustainable. Hence, the use of plant extract-based organic corrosion inhibitor meets the requirements of low-carbon and green chemical industry, which is conducive to achieving the goal of carbon peak and carbon neutralization in China. The use of plant extract-based organic corrosion inhibitors to prevent metal corrosion has attracted intensive attention. In this review, the research progress of natural plant extracts as metal corrosion inhibitors in recent two decades is analyzed, and the scientific basis and application of plant extracts-based organic green corrosion inhibitors are discussed. Plant extracts containing abundant heteroatomic groups are prone to process physical or chemical interaction with metal surface for the formation of adsorption films, which hinders the direct contact between metal surface and aggressive species. Thus, the electrochemical reaction on metal surface is blocked or inhibited. This helps us in realization of the protection of metal corrosion in different aggressive media and prevention of metal dissolution. This paper also gives perspective of research focus and objectives in this field, and guides us to explore organic corrosion inhibitors based on natural products.