Nanoporous tungsten with tailorable microstructure and high thermal stability

Abstract Nanoporous tungsten was prepared by a strategy combining mechanical alloying and chemical dealloying at room temperature. The feature size of the nanoporous structure is adjustable by modifying dealloying medium and duration. The formation of nanoporous tungsten is dependent on the surface diffusion of W atoms and their diffusivity in the dealloying medium is in a magnitude order of 10−20 m2 s−1. The structure of nanoporous tungsten has a high activation energy for surface diffusion, which contributes to its extremely high thermal stability. The nanoporous tungsten may be promising for applications at high temperatures.