Shape-controlled synthesis of GaN microrods by ammonolysis route

It would be interesting to synthesize GaN with various morphologies for different applications. Herein, the synthesis of GaN microrods is demonstrated. The synthesis involved two steps: first, hydrothermal synthesis of GaOOH microrods at 190 °C for 24 h; second, preparation of GaN microrods in the flow of NH3 gas at 850 °C for 90 min. The synthesized GaOOH and GaN microrods were characterized by FESEM, suggesting that the initial GaOOH structural motifs were unaffected by the high temperature chemical transformations process. It was found that a slower heating rate (1 °C min−1) is beneficial to keeping the 1D skeleton of and GaN, while GaN nanoparticles with minor microtubes were obtained with a higher heating rate (10 °C min−1). Raman spectroscopy and PL spectrum of the as-prepared GaN product have been performed. The photoluminescence measurement reveals that the as-prepared wurtzite GaN microrods showed strong blue-violet emission.