Nitrogen plasma-driven structural modulation of ZnO nanorods for enhanced UV-Visible photosensing

Abstract

Zinc oxide (ZnO) nanorods exhibit promising optoelectronic properties, which can be further tuned through defect engineering and compositional modulation. In this study, highly crystalline ZnO nanorods were synthesized using an atmospheric pressure plasma system and doped with nitrogen via vacuum plasma treatment under varying powers and durations. Structural analyses revealed that harsher plasma conditions induce nanorod deformation, lattice strain, and bond length contraction. XRD and Raman analyses confirmed bond length variations and defect-related peak shifts, while XPS and PL analyses identified nitrogen-related species including Zn3N2 and alpha-/beta-/gamma-N. Under optimized conditions, UV photocurrent increased from 0.29 to 2.36 mu A (375 nm), while visible-light photocurrent reached 9.8 mu A (450-720 nm), indicating significantly enhanced photosensing behavior and clear correlations to structural modulation. These findings demonstrate a versatile platform for high-performance photodetectors and next-generation optoelectronic devices.