Silicon carbide nano-rods was synthesized by the pyrolysis of a polysilazane preceramic precursor in the presence of 3%(mass fraction) FeCl

2

as a catalyst under 1700 ℃.SEM

XRDand EDXwas employed to characterize their structure and component.XRDpattern demonstrated that nano-rods consist of 3C-SiCas a sole type of crystalline with a plenty of stack fault

and no trace indicated a-SiC polytypes.The ratio of silicon and carbon is estimated as close to 1:1 based on EDXsemiquantitative estimation. Electron microscopy results revealed that the SiCnanorods of 80～200 nm in diameter and several hundred micrometers to a few millimeters in length preferentially grow along(111) direction.Optical properties of nanorods were studied using micro-Raman spectrum

photoluminescence and optical band edge Absorption.In PLspectra an intensive emission at 3.27 eV was observed

and a weak broad emission band was located at low energy side about 2.4 eV

while the optical absorption spectra revealed that there is an optical Absorption edge at the identical energy level mentioned above.However

the optical Absorption spectra showed a complex structure.In order to get more definite information

Raman spectra were measured on these SiCnanorods.Raman spectrum gives a sharp scattering peak at near 800 cm

-1

with a shoulder multiply peak at low energy side.Using Gaussian peak fitting

we found that it contains two peaks at 799.6 and 777 cm

-1

corresponding to the TOmode for 3C-SiC and a-SiC respectively.Basis of the results of XRD

Raman

optical absorption and PL emission

we conduced to one supposition that the SiC nanorods are mixing-polycrystal with a multi-layer structure.