Raman scattering and photoluminescence of quasi-aligned ternary ZnCdO nanorods

Abstract

Ternary ZnCdO single-crystal nanorods with a high Cd incorporation of about 16 at% were synthesized onto Au-catalyzed Si substrate using a physical vapour deposition method. Field emission scanning electron microscopy observation, x-ray diffraction analysis and Raman spectrum showed that the ZnCdO nanorods were well-aligned along the c-axis. Raman spectrum revealed that the E2 (high) mode of the ZnCdO nanorods shifted towards the higher frequency side by 5 cm−1 with respect to that of pure bulk ZnO, corresponding to biaxial compressive stress of 1.14 GPa. The near-band-edge emission of ZnCdO red-shifted to 3.04 eV due to Cd substitution. The defect-related emission exhibited anomalous phonon replicas with an energy of 102 meV, which was attributed to the disorder-activated B1 phonon mode.