Preparation of super-hydrophobic BN nanotube mesh and theoretical research of wetting state

Abstract

In this study, we have fabricated stainless steel mesh with columnar super-hydrophobic boron nitride nanotubes (BNNTs) through the ‘gas-liquid-solid’ mechanism annealing method. We employed iron (Fe) powder as the catalyst and utilized boron (B) and boron oxide (B2O3) as the raw materials. The synthesis took place within a tubular furnace, operating under an NH3 atmosphere at a temperature of 1250C∘. The contact angle of water droplets on the experimental surface measures approximately 150∘, while the sliding angle is approximately 3∘. In the next place, the laboratory carried out a series of experiments on the tensile properties, corrosion resistance, and erosion resistance of the prepared samples. The experimental results showed that the sample material had good mechanical properties and corrosion resistance. In addition, the erosion resistance test results showed that the sample material even at high speed (2800 rpm/min). After washing the sample for 5 min, the surface of the material still has good wettability (contact angle is 136.49∘). Finally, droplet bouncing experiments have demonstrated that the adhesion force on the surface of the boron nitride nanotube stainless steel mesh is notably minimal, indicating its substantial hydrophobic properties. Additionally, we conducted an investigation into the wetting interaction between droplets and the surface of the boron nitride nanotube stainless steel mesh. By applying the Wenzel and Cassie formulas and considering the pertinent geometric parameters of the material surface, we theoretically elucidated that, upon contact, the droplets assume a ‘Cassie’ state on the surface of the super-hydrophobic boron nitride nanotube stainless steel mesh. The research results show that the superhydrophobic boron nitride nanotube stainless steel mesh has broad application prospects in the fields of hydrogen storage, sewage treatment and oil-water separation.