Facile methods for fabricating wettability patterns on metal substrates

Extreme-wettability-patterned surfaces have attracted great attention due to their excellent application prospects for liquid manipulation. However, developing a simple and universal method to fabricate wettability patterns on a variety of metals remains a great challenge. In this work, three specific preparation approaches were developed to fabricate wettability patterns on copper substrates using chemical processing combined with mask technology. Surface wettability can be suitably controlled by changing the solution concentration and immersion time. The surface has good stability and low pollution under external action. The three preparation methods have differences in preparation process, wettability and mask function. On the basis of these approaches, various complex wettability patterns could be prepared on different metal substrates using designed masks. Furthermore, various wettability-patterned surfaces were successfully fabricated for liquid manipulation applications, such as controlling the fluid shape and water transport. The methods proposed are expected to have promising application potential in patternable printing, water collection and heat-dissipation devices.