Preparation of α-Si3N4 nanorods assembled nanobelts by crystallizing amorphous Si3N4 powders.

In this paper, a new nanomaterial, α-Si 3 N 4 nanobelts assembled by high density nanorods were prepared via the crystallization of amorphous Si 3 N 4 at 1450 °C for 12 h. The as-synthesized nanobelts exhibited a width of ∼900 nm and a thickness of ∼150 nm, and a depressed linear region in the central. α-Si 3 N 4 nanorods on the nanobelts had a width of 8–16 nm and a length of 400–450 nm. The nanorods were single-crystal, growing along (101) plane. The nanobelt appeared to be initiated by α-Si 3 N 4 nanorods constantly growing on the both sides of a nanowire which was caused by secondary nucleation and the growth of Si 3 N 4 microcrystals. Growth mechanism related to the formation of the nanobelts was analyzed in detail on the basis of vapor-solid mechanism and secondary nucleation. The current work would provide new insights into α-Si 3 N 4 nanobelts assembled by nanorods which play an important role in nanoscale devices and show widespread potential applications due to their special morphology. • α-Si 3 N 4 nanobelts assembled by nanorods were prepared from amorphous Si 3 N 4 powders. • The α-Si 3 N 4 nanorods constantly grow on the both sides of a nanowire. • Two emission peaks at 437 nm (2.84 eV) and 462 nm (2.68 eV) was measured in the photoluminescence (PL) spectrum. • The growth mechanisms of the α-Si 3 N 4 nanobelts were vapor-solid mechanism and secondary nucleation. [ABSTRACT FROM AUTHOR]