Fig. 1. X-ray diffraction patterns of the samples fabricated at 950 ℃ and 1000 ℃ (Reaction time is 2 h)

Fig. 2. SEM images of GaN samples fabricated at different reaction time (Reaction temperature is 1000 ℃): (a) 0.5 h, (b) 1 h, (c) 2 h; (d) SEM image of GaN sample fabricated at 950 ℃.

Fig. 3. TEM images of GaN nanowires fabricated at 1000 ℃ (Reaction time is 2 h): (a) TEM image of single GaN nanowire; (b) HR-TEM image of GaN nanowire in (a); (c) TEM image of another GaN nanowire; (d) HR-TEM image of GaN nanowire in (c).

Fig. 4. Raman spectra of GaN nanowires fabricated at 1000 ℃ (Reaction time is 2 h).

Fig. 5. Growth mechanism diagram of GaN nanomaterials.

Fig. 6. PL spectrum of GaN nanowires fabricated at 1000 ℃ (Reaction time is 2 h).