Catalytic synthesis of Ti2S nanofibers

Dititanium sulfide (Ti2S) nanofibers were synthesized through chemical reac tions from gaseous reagents of TiClx, H2S, and S with the help of Ni cataly sts at elevated temperature (950 degreesC). Highly dispersed Ni nanoparticl es and H2S (or S) gases were obtained by decomposing the preintroduced NiSO 4 nanoparticles confined in the pores of activated carbon in a reducing H-2 atmosphere. The active Ni catalyst provides an energetically favored site for the absorption of gaseous TiClx, H2S, and S to form an ultrafine liquid alloy droplet containing Ti and S atoms. Then a vapor-liquid-solid growth was involved in the formation of Ti2S nanofibers. SEM and TEM investigation s show that the Ti2S crystals grew in the form of nanofibers with diameters mainly around 20 similar to 50 nm and lengths up to several tens of microm eters. Most Ti2S nanofibers have smooth surface with a quadrilateral, trian gular, or hexagonal cross section, while the others have a wavy appearance.