Synthesis and Characterization of Colloidal InP Quantum Rods

InP nanorods and nanowires in the diameter range of 30-300 Å and 100-1000 Å in length were synthesized. For the preparation of nanorods, we used an organometallic precursor that decomposes thermally into InP and In metal particles. The latter serves as a nucleation catalyst for the growth of the semiconductor. Quantum rods of zinc blende structure with a high degree of crystallinity are grown along the (111) crystallographic planes. The absorption spectrum of InP nanorods with diameter of about 30 Å. and 100-300 Å in length is in the visible spectral regime, suggesting a substantial blue shift with respect to the bulk (band gap 1.35 eV) that is due to size confinement. Moreover, the Stokes shift of the emission band in the quantum rods is substantially larger than the shift in the corresponding quantum dots.