Study on controlled Al-doped single-crystalline Si₃N₄ nanobelts

Controlled Al doped Si₃N₄ single-crystal nanobelts were synthesized by catalyst-assisted pyrolysis of polymeric precursors. The Al-doping levels can be tailored by varying the Al concentration in the polymeric precursors. The as-synthesized nanobelts were characterized by SEM, XRD, EDS, TEM and HRTEM. The single-crystal belts had perfect crystal structures with few defects such as dislocations and stacking faults. The nanobelts obtained are several tens nanometers in thickness, several hundreds nanometers in width. The growth direction of the Al doped α-Si₃N₄ nanobelts was [011]. The growth mechanisms of α-Si₃N₄ nanobelts were proposed to be solid-liquid-gas-sold (SLGS). The optical properties of Al doping Si₃N₄ nanobelts were measured. Current results suggested that the optical properties of the nanomaterials can be controlled by adjusting Al doping contents.