Superhydrophobic materials offer an innovative strategy for developing marine anti-corrosion materials due to their extremely low solid-liquid contact area and low surface energy. However, existing superhydrophobic anti-corrosion materials often suffer from poor mechanical stability and inadequate long-term protection, limiting their practical application in real-world environments.

In a recent breakthrough, a research team led by Prof. ZHANG Binbin from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) developed an ultra-robust superhydrophobic composite coating with high mechanical stability and long-term anti-corrosion performance by utilizing recycled tire rubber (RTR) particles as armored skeleton structure. Their findings were published in Chemical Engineering Journal.

Inspired by the wear-resistant, weather-resistant, and cushioning properties of multi-layered rubber running tracks, and motivated by concerns over resource waste, environmental pollution, and recycling challenges associated with accumulated waste rubber tires, the researchers innovatively designed a triple-layered superhydrophobic anti-corrosion coating using RTR particles as skeleton structure. This approach achieves both high-value recycling of waste and high-performance anti-corrosion coating design.

The as-prepared RTR armored superhydrophobic composite coating demonstrated exceptional surface stability, maintaining its superhydrophobicity after withstanding 1200 cycles of sandpaper abrasion, 450 cycles of tape-peeling tests, and 1050 g of sand impact.

Electrochemical impedance spectroscopy (EIS) revealed that the charge transfer resistance and low-frequency impedance modulus of the coated Q235 carbon steel substrate increased by seven orders of magnitude, while the corrosion current density decreased by five orders of magnitude. The coating showed no signs of failure or corrosion after 840 h of 3.5 wt.% NaCl immersion and 1680 h of marine atmospheric exposure, highlighting its excellent long-term anti-corrosion performance.

The designed RTR armored superhydrophobic coating not only enables resource recycling but also provides an innovative pathway for developing highly wear-resistant and weather-resistant functional protective materials. "We believe that with continued improvements in the stability and durability of superhydrophobic anti-corrosion materials, they will play a key role in a broader range of applications in the future," said Prof. ZHANG, the first and corresponding author.

Graphical Abstract of the Development of Highly Robust Superhydrophobic Anti-Corrosion Coating Using Recycled Tire Rubber Particles. (Image by IOCAS)

(Text by ZHANG Binbin)