Octadecylsilane is widely used as a surface modifying agent in various industries. It is applied to alter the surface properties of materials, making them hydrophobic. This characteristic is particularly valuable in the production of water-repellent coatings for glass, metals, and ceramics. In chromatography, octadecylsilane is a key component in the stationary phase of reverse-phase columns, enhancing the separation of non-polar compounds. Additionally, it is utilized in the manufacturing of nanoparticles and nanocomposites to improve their dispersion and stability in non-polar media. The chemical also finds applications in the development of self-assembled monolayers (SAMs) for sensors and electronic devices, where it aids in controlling surface interactions and improving device performance.