Synthesis and evaluation of silicon dioxide nanoparticle coating as corrosion inhibitor for mild steel

Corrosion is a material removal process in which a refined metal is converted into a chemically stable oxide. This process is the gradual deterioration of materials by chemical or electrochemical reactions with their environment. Corrosion is heavily influenced by environmental factors such as air, moisture, water, and temperature. This study aims to minimize corrosion resistance by applying silicon dioxide nanocoating to mild steel. Silicon dioxide nanomaterials are synthesized with a precursor using the sol–gel method and coated on a mild steel substrate using a spin coater. A corrosion test is conducted on the sample to determine inhibition efficiency and corrosion rate. The nanocoated substrate is tested in a NaCl solution. The characterization techniques of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) tests are conducted on the substrate. SEM results show the morphology and structure of the coated and uncoated substrates. Nanomaterials are distributed uniformly on the substrate in the third and fourth layers of coating. The absence of cracks in the third and fourth layers of coating can be attributed to the uniform deposition of nanomaterials and the required amount. EDS results indicate the presence of elements or compositions in the nanocoating. The corrosion test result reveals that corrosion rate decreased and inhibition efficiency increased up to three coatings. If more than three coatings are present, then the corrosion rate is increased due to micelle formation.