Preparation of Co3O4 self-cleaning nanocoatings: Investigation of ZnO seeded steel meshes

Abstract In this study, superhydrophobic Co3O4 surfaces with micro/nano hierarchical structures were synthesized on the stainless steel mesh (type: 304, size: #50) by the chemical bath deposition (CBD) method. Taguchi L9 experimental design was applied to evaluate the influence of the type and concentration amounts of the additives, the zinc salt solution concentration as the seeding medium, and the reaction time. After surface modification, the sample synthesized under the optimized conditions showed superhydrophobic properties with the water contact angle (WCA) of 162.6±2.6° and contact angle hysteresis (CAH) of 2˚. X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR), and Energy Dispersive X-ray (EDX) analyses were used to characterize the synthesized samples. The FESEM images of the optimum sample confirmed the formation of the flower-like structures assembled from numerous petals with thicknesses of ~50 nm to 95 nm. The chemical stability and the self-cleaning characteristics of the obtained superhydrophobic surface were also investigated. Results of the assessments showed that the Co3O4 superhydrophobic surfaces were exhibited an excellent self-cleaning performance.