Controllable wettability by tailoring one-dimensional tellurium micro–nanostructures

Abstract

Controllable wettability is significant for fundamental research and practical applications such as smart and fluid-controllable devices, cell proliferation and inkjet printing. In this work, four one-dimensional Te micro–nanostructures have been fabricated by one-step physical vapor deposition method on the surface of the widely used engineering material FeCoCr alloy. The top morphology and framework of the one-dimensional Te micro–nanostructures can be precisely controlled by the source and deposition temperature, which enables us to design the desired wettability of a solid surface. The wettability of the FeCoCr alloy surface dramatically changes from the near-superhydrophilicity of a Te microscale triangle array to the complete superhydrophobicity of a random-oriented Te nanoscale needle array. Significantly, a complete non-stick superhydrophobic surface with a contact angle of 171° is achieved, for the first time, by adjusting the framework of Te micro–nanostructures from needle microrod arrays to random-oriented needle nanowire networks, which form a special three dimensional (3D) nanoporous network structure. The controllable wettability is suggested to arise from the synergy between the roughness and the framework of Te micro–nanostructures. Our finding not only opens an avenue for the application of Te micro–nanostructures but also paves a way towards the design for controlling the wettability of one-dimensional micro–nanostructure arrays.