Efficient surface engineering of aluminum foil by using piranha solution strategy

The diverse silanes grafted onto the surface of aluminum and its alloys offers various functions in high-performance applications from enzymatic surface reaction to sensor purposes. The chemical etching is a basic technique for initiating silanization on surfaces but challenges remain in refining modification conditions and investigating the grafting mechanism. Here, a piranha solution (PS) strategy with mild treatment conditions by either acid or base PS is applied to tune the surface architecture and properties of aluminum foil. Optimal PS activation conditions are found in 20 vol% base PS after 60 min treatment. Subsequently, perfluorinated and non-perfluorinated silanes were grafted onto the surface of PS activated aluminum foil using the grafting to mode. More than 41.3 x 10(-6) mol cm(-2) hydroxyl groups and a hydrophilic surface (CA=31.3 +/- 3.3 degrees) were obtained from the base PS activated aluminum foil. A 43.4% grafting efficiency for silanes was introduced on the surface of the activated foil. This study is expected to open doors for the further PS studies on metallic substrates in various applications.

Automated summary

This study investigates the surface modification of aluminum foil using a piranha solution (PS) strategy with mild treatment conditions. The results show that optimal activation conditions are achieved with base PS treatment. The study demonstrates the potential application of PS on metallic substrates in various fields.