Electron paramagnetic resonance and 1H nuclear magnetic resonance study of Y-doping effect on the hydrogen shallow donors in ZnO nanoparticles

Hydrogen shallow donors in sol-gel-derived pristine and rare-earth Y-doped ZnO nanoparticles have been investigated by electron paramagnetic resonance (EPR) and high-resolution ¹H nuclear magnetic resonance (NMR). It is shown by EPR measurements that the energy level of the hydrogen shallow donors in the Y-doped ZnO is much deeper (E ～ 174 meV) than in the pristine ZnO (E ～ 75 meV). The temperature-dependent ¹H NMR chemical shift and linewidth measurements of the pristine and the Y-doped ZnO systems indicated that Y-doping effectively modifies the lattice environment and hinders the hydrogen motions in the ZnO nanoparticles.