Synthesis of germanium nitride nanowires

The two types of single-crystalline alpha-Ge₃N₄ nanowires (NWs) were synthesized at 550degC by annealing the crystalline Ge sample in the hydrazine vapor containing 3 mol.% of water. The mass transfer was accomplished by volatile GeO molecules. The tapered NWs were grown by the vapor-liquid-solid method with ~8 nm Ge catalyst droplet surrounded by ~5 nm thick GeO_x shell. NWs with uniform diameters were formed on the same sample by the oxide-assisted growth method. In the photoluminescence spectra of NWs the five peaks were observed in the blue-green region with energies close to the photoluminescence peaks of germanium suboxides.