Using acetylene as carbon source, high yield of carbon coils could be synthesized directly over Al 2 O 3 substrate through the decomposition of acetylene at 500°C. The microstructure and photoluminescence (PL) properties of the obtained carbon coils were investigated in detail. The results demonstrate that the as-synthesized carbon coils exhibit a strong ultraviolet (UV) PL peak at 365nm and a sideband peak at 465nm. By increasing the excitation wavelength from 220 to 300nm, the UV PL could be enhanced. Because of the as-synthesized carbon coils directly growing over Al 2 O 3 substrate, the proposed route for the synthesis of carbon nanomaterials may expand their utilization in electronics effectively.