Facile synthesis of powder-based processing of porous aluminum nitride

The use of aluminum nitride (AlN) has recently begun to be explored for advanced functional applications. For some particular applications, it is more advantageous to use porous-structured AlN, simply because it can provide a greater surface area and higher permeability. However, porous or bulk AlN is very difficult to achieve due mainly to its high melting point (2200 °C). This study proposes a new novel processing method to synthesize porous AlN through a complete transformation from porous aluminum (Al) using a remarkably low nitriding/sintering temperature (620 °C) as opposed to only the surface nitride AlN-Al core composite systems reportedly at or above 1000 °C in the literature. A uniform microporous bead structure of porous AlN with a mean pore size of 74.0 ± 27.7 μm was obtained that also contained nanoparticles ranging from 80 to 230 nm that covered the surface.