### Nanomaterials/Nano-Modified Coatings as Corrosion Inhibitors  
Today, nanotechnology is a rapidly expanding subject with uses in academia. Due to their outstanding and distinctive basic physicochemical characteristics, including greater external region, mechanical characteristics, optical activity, and chemical reactivity, NPs with sizes ranging from 1 to 100 nm have been used in a variety of production, ecological, health sciences, agricultural, and food applications [37; 38; 39]. The most significant use of NPs in the industrial sector is their ability to preserve metal from corrosion in distinct predicaments. Metals are employed as basic materials or fundamental materials in enterprises and several other fields due to their many appealing features, including electrical and thermal conductance, increased boiling and melting ranges, greater compressive strength, greater mass-to-volume fraction, and flexibility. Electrochemical interactions involving metals and their surroundings occur when metals engage with their environment [40; 41]. A variety of methods are employed to slow the corrosion rate (C\({}_{\text{R}}\)), including metallic surface treatment, environmental alterations, the application of CIs, and changes in pH and utilization of coatings. As compared to their typical macroscopic counterparts, nanomaterials (NMs) and their additives have a high surface-to-volume ratio, making them effective CIs [42; 43]. By obstructing the active surface area on the metallic substrate, NMs restrict the pace of corrosion and halt surface reactions. They also give toughness, flatness, endurance, optical properties, and heat resistance. These substances are eco-sustainable and biodegradable. This review article's goal is to examine novel and effective methods for employing NP-based coatings/nano-modified coatings to generate more potent CIs and corrosion mitigation for several metals and alloys. Over the past decades, various nanomaterials have been used by numerous research teams based on their suitability for anti-corrosion purposes. Here, some of them are examined together with their additives and exceptional anticorrosive properties. In an experiment, to utilize nano-modified coatings in defensive coverings to avail CIs in the long term, [PERSON] et al. [18] created sodium carboxymethylcellulose (CMC-Na) microparticles carrying benzotriazole (BTA) as CIs. The produced biopolymeric CMC-Na microparticles were morphologically evaluated using SEM, and their discharge characteristic was investigated by UV-Vis. The findings demonstrate that the microparticles that were created were uniform, circular, and of a matrix sort of character. SEM morphologies of the spray-dried particulates produced under various testing circumstances are shown in Figure 4. It is clear to see that, independent of the empirical conditions, all microparticles exhibited a spherical form with a flawless substrate as their most distinguishing feature. The dearth of coatings or incrustations on the microspheres' substrates together with their uniform texture indicates that the CIs were disseminated throughout the biopolymeric matrix. Spherical-shaped particulates with homogeneous substrates were frequently produced when this family of biopolymers was used. The suitable proportion (1.25:1) amongst the encapsulated substance and the encasing polymeric matrices, together with the usage of poly (vinyl alcohol) (PVA) as a plasticizer in this study, helped to generate homogenous particulates. A preferred approach to improve the elasticity, hardness, and impact strength of polymeric coatings while reducing instability is the inclusion of plasticizers. Thus, it is probable that PVA reduced the intermolecular contacts in the CMC-Na matrix, increased polymeric chain motion, and, as a consequence, enhanced the physical characteristics of the resultant particulates and enhanced the corrosion mitigation of the nano-modified coatings. Moreover, it was found that the spray flow volume and input temperature had a big impact on the procedure outputs and discharge patterns.