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In the current study, Y-doped vertically aligned ZnO nanowires are grown on p-Si substrates by employing cost-effective double-step chemical bath deposition technique. The doping percentages are varied systematically (YxZn1-xO, x= 0.0, 0.01, 0.02, 0.03, 0.04 M) to investigate the impact of rare earth doping on structural, optical and luminescence properties of ZnO nanowires. The crystalline quality, morphology, optical absorbance and defect states of grown nanowires are studied extensively by employing XRD, FESEM, UV-VIS and room-temperature PL. XRD results reveal that Y-doped ZnO nanowires have single phase hexagonal structure without any extra peaks related to the Y-mixed oxides. FESEM analysis indicates that the dopant with higher radius dose not affected the morphology of ZnO nanowires. The optical energy band gaps of such nanowires are calculated by employing UV-VIS spectroscopy and values are estimated to be 3.11 eV to 2.97 eV. The absorption coefficient, reflective index and extinction coefficient are also extracted and analysed for all of such nanowires. PL results showed that the undoped ZnO nanowires exhibit low UV emission (374 nm) and relatively high green emission (552 nm), whereas, after a low amount of Y doping, UV emission peak enhanced along with an additional blue emission peak at 437 nm. Such blue emission peak is associated with the Zn interstitials related defects, which is generally responsible for the enhancement of donor concentrations in ZnO. Significantly, the oxygen vacancy related green emission peak reduces gradually with increasing Y incorporation. The work provides a detailed study on optical properties of Y-doped ZnO nanowires, which is essential for developing the next-generation heterojunction based optoelectronic devices.
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