Synthesis of long indium nitride nanowires with uniform diameters in large quantities

Large quantities of indium nitride (InN) nanowires are synthesized by the in situ nitriding of indium oxide (In2O3) powders in an ammonia (NH3) flux. Tens of milligrams of nanowires are obtained in one batch. Every 100 mg of In2O3 starting powder can produce up to 65 mg of InN nanowires under the optimized conditions. The synthesized nanowires grow along the [001] direction with excellent crystallinity. They are of high purity and are 30-50 mu m in length with an almost uniform diameter of about 100 nm. Photoluminescence measurements of the nanowires exhibit a strong peak at 707 nm. An optical bandgap of about 1.7 eV is estimated based on the absorption spectrum. The experimental results also demonstrate that the approach of nitriding In2O3 powders in situ is feasible for the synthesis of high-purity InN nanowires in large quantities, with good reproducibility and without catalyst materials. The synthesis of InN nanowires in large quantities would be of benefit to the further study and understanding of their intrinsic properties, as well as being advantageous for their potential application in nanodevices.