Structure and Raman scattering of Mg-doped ZnO nanoparticles prepared by sol–gel method

Mg-doped ZnO (Mg x Zn1−x O, x = 0–0.10) nanoparticles were prepared by sol–gel method. Structural characterization by X-ray diffraction (XRD) indicates that the lattice parameter a increases and c decreases linearly with the increase in Mg content (x) due to the substitution of Mg2+ for Zn2+ in ZnO lattice. The blueshift of Raman modes is observed, impling the increase in force constant of atom vibration in the Mg x Zn1−x O (MgZnO) nanoparticles. Resonant Raman spectra show longitudinal optical phonon overtones up to fifth order, revealing that the short part of the electron–phonon interaction is enhanced and long-range part is weakened by Mg doping.