Surface plasmon driven enhancement in UV-emission of electrochemically grown Zn1−xCdxO nanorods using Au nanoparticles

Highlights: ► Zn1−xCdxO (0 < x < 0.16) nanorods have been synthesized by electrodeposition. ► No mixed phases are observed up to x = 0.16. ► A bandgap tuning of 0.20 eV obtained. ► 12-Fold enhancement in the UV-emission intensity for x = 0.04 achieved. -- Abstract: Zn1−xCdxO (0 < x < 0.16) alloys semiconductor nanorods having a diameter of 80–150 nm and length ∼2 μm has been synthesized by electrodeposition. Au-nanoparticles (Au-NPs) have been sputtered on the Zn1−xCdxO nanorods for different sputtering times (from 0 to 100 s). The photoluminescence (PL) spectra of bare Zn1−xCdxO nanorods showed a weak bandgap emission in UV region and a broad defect-related emission band in the visible region of the electromagnetic spectrum. The UV-emission attains maximum intensity for the 50 s Au sputtered ZnCdO nanostructures and this enhancement in intensity is due to the transfer of electrons from defect states within the bandgap of ZnCdO to the Au-NPs that cause an increase of resonant electron density. These resonant electrons escape from the surface of the 99 Au-NPs to conduction band of ZnCdO nanorods leading to the suppression of defect related emission intensity. The suppression of defects related emission decreased with higher cadmium concentration in Zn1−xCdxO nanorods