Fabrication of Pd nanoparticles on Al substrate with excellent superhydrophobicity and photocatalytic activity

A stable palladium superhydrophobic surface (PdSHS) with static water contact angle of 161 ± 1° and sliding angle of 2° was fabricated on aluminum (Al) substrate through etching, deposition, and anneal process. The chemical composition, surface texture, and morphology were tested by X-ray diffraction pattern, X-ray photoelectron spectroscopy, scanning electron microscopy, along with energy dispersive spectroscopy. Pd nanoparticles were organized on micro and nanoscale on rough Al substrate. The electrochemical impedance spectroscopy was explored to test anti-corrosion behavior of PdSHS that is enhanced significantly than that of Al substrate. The environmental stability, durability and large size of PdSHS are also investigated with satisfactoried results. The photodegradation rate, chemical reaction constant and half-life of methylene blue are 98.31%, 5.89 × 10⁻² s⁻¹, and 5.27 min respectively when the PdSHS was as photocatalyst, which is much better than that of superhydrophilic sample. The photocatalytic degrading proficiency of PdSHS remains relatively stable even after 11 cycles. These can enhance industrial applications of the Pd nanoparticles on Al substrate and its alloys.