A facile method to prepare stearic acid-TiO2/zinc composite coating with multipronged robustness, self-cleaning property, and corrosion resistance

Abstract

Despite that some superhydrophobic coatings have been developed to enhance the corrosion resistance of steel, there lacks a solution that also fulfills both robustness and service durability. Taking advantage of the controlled generation of particles during electrodeposition, a multifunctional stearic acid (STA)-TiO2/zinc composite (TZC) coating with hierarchical micro/nanostructures by codeposition of TiO2 nanoparticles and zinc ions was prepared on carbon steel substrates. The structures of STA-TZC coating were characterized by a series of means. The micro/nanoscale structured surface based on TZC with STA overcoat imparted the prepared STA-TZC coating with outstanding superhydrophobic property; the water contact angle and sliding angle were 160±1.4° and 5.4±0.2°, respectively. According to the tests of knife scratching, adhesive tape peeling, sandpaper abrasion, and chemical corrosion resistance, the STA-TZC coating presented good mechanical and chemical stabilities. Additionally, STA-TZC coating showed excellent self-cleaning property, corrosion resistance, and superhydrophobic stability. The results indicated that filling the voids of porous zinc coating with TiO2 nanoparticles and subsequently modifying with STA film could greatly improve the coating’s resistance to corrosion and mechanical abrasion. This electrochemical codeposition-modification method has broad application prospects for exploring and preparing metal-based superhydrophobic coatings.