Fabrication of bismuth superhydrophobic surface on zinc substrate

The dendritic Bi/Bi₂O₃/ZnO superhydrophobic surface (SHPS) was facilely obtained on zinc substrate via etching in 0.5 mol L⁻¹ HCl solution for 2 min, immersing in 2 mmol L⁻¹ Bi(NO₃)₃/0.1 mol L⁻¹ HNO₃ solution for 2.5 min and annealing treatment at 180 °C for 2 h. The wetting property results demonstrated that the superhydrophobic sample had excellent water-repellency with a static water contact angle of ~ 160° and sliding angle of ~ 0° under the optimum condition, which can be visually confirmed by the impacting droplet could rebound back immediately and roll off the horizontally placed sample. Moreover, it exhibited remarkable self-cleaning ability, buoyancy, desired stability in long-term storage in air, corrosion resistance in 3.5 wt% NaCl solution, ice-over delay at − 16 °C and durability in lab-simulated abrasion test.