title: NMR Observation of Mobile Protons in Proton-Implanted ZnO Nanorods.
abstract: The diffusion properties of H(+) in ZnO nanorods are investigated before and after 20 MeV proton beam irradiation by using (1)H nuclear magnetic resonance (NMR) spectroscopy. Herein, we unambiguously observe that the implanted protons occupy thermally unstable site of ZnO, giving rise to a narrow NMR line at 4.1 ppm. The activation barrier of the implanted protons was found to be 0.46 eV by means of the rotating-frame spin-lattice relaxation measurements, apparently being interstitial hydrogens. High-energy beam irradiation also leads to correlated jump diffusion of the surface hydroxyl group of multiple lines at ~1 ppm, implying the presence of structural disorder at the ZnO surface.
authors.affiliation: Korea Multi-purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju 38180, Korea.|Korea University of Science and Technology, Daejon 34113, Korea.
authors.forename: Jun Kue
authors.initials: JK
authors.lastname: Park
authors.affiliation: Korea Multi-purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju 38180, Korea.|Korea University of Science and Technology, Daejon 34113, Korea.
authors.forename: Hyeok-Jung
authors.initials: HJ
authors.lastname: Kwon
authors.affiliation: Department of Physics, Korea University, Seoul 02841, Korea.
authors.forename: Cheol Eui
authors.initials: CE
authors.lastname: Lee