采用溶胶凝胶法制备的前驱物进一步在900℃,氨气气氛中氮化得到粒径相对均匀、平均粒径为11.2rim的六方相氮化镓纳米晶体。XRD,HRTEM,SAED,EDS,FTIR被用于表征产物的微结构及组成。室温光致发光光谱显示产物位于3.46eV的带边发光峰和从2.6~3.2eV的宽的发光带。产物可直接用于制备氮化镓量子点复合材料和制备高质量的一维氮化镓晶体。
Single-phase wurtzite GaN nanocrystals With an average diameter of 11.2 nm were synthesized through a sol-gel technique and subsequent nitrition. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) confirmed they had a hexagonal structure and a narrow size distribution of the nanocrystals. X-ray powder diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) measurement showed that the GaN powder was of single-phase wurtzite structure with a considerable fraction of structural defects such as tWin and stacking faults. The IR spectrum showed that only the Ga-N stretch is present at 580cm-1. Room-temperature photoluminescence measurement revealed a broad emission ranging from 2.6 to 3.2 eV With some fine structures, which are believed to be associated With the defect levels.