Steel is used to manufacture a wide range of products from tiny surgical tools to huge ships. However, it can become corroded or contaminated when liquid comes into contact with it. A new method to coat steel with the compound tungsten oxide has been reported by researchers from Harvard University in Nature Communications this week. It enables liquid to slip off the surface while keeping the steel strong. Dr Ben de Laune, a materials chemist from the University of Birmingham, explains to Rosalind Davies why this is so important.