Porous WS2 and W2N powders by hard templating with colloidal silica

Meso- and macroporous tungsten disulfide (WS2) and tungsten nitride (W2N) powders were successfully synthesized by reduction of [WO3/colloidal silica] composites under hydrogen sulfide and ammonia gases respectively. The colloidal silica, marketed as Ludox®, was used as a hard template and its removal from the composite led to a porosity release. The products were characterized by X-ray diffraction, nitrogen adsorption, mercury porosimetry and electron microscopy. Well-crystallized samples with specific surfaces areas close to ~40 m2 g−1 were thus synthesized. The present approach might be easily extended to the synthesis of other nitrides and sulfides materials.