Eu3+-Doped Wide Band Gap Zn2SnO4 Semiconductor Nanoparticles: Structure and Luminescence

• Published in: Journal of physical chemistry. C Vol. 120; no. 33; pp. 18887 - 18894
• Main Authors: Dimitrievska, Mirjana, Ivetić, Tamara B, Litvinchuk, Alexander P, Fairbrother, Andrew, Miljević, Bojan B, Štrbac, Goran R, Pérez Rodríguez, Alejandro, Lukić-Petrović, Svetlana R
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 25.08.2016
• Subjects: analysis; doping; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; nanoparticles
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.6b05335

Nanocrystalline Zn2SnO4 powders doped with Eu3+ ions were synthesized via a mechanochemical solid-state reaction method followed by postannealing in air at 1200 °C. X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and Raman and photoluminescence (PL) spectroscopies provide convincing evidence for the incorporation of Eu3+ ions into the host matrix on noncentrosymmetric sites of the cubic inverse spinel lattice. Microstructural analysis shows that the crystalline grain size decreases with the addition of Eu3+. Formation of a nanocrystalline Eu2Sn2O7 secondary phase is also observed. Luminescence spectra of Eu3+-doped samples show several emissions, including narrow-band magnetic dipole emission at 595 nm and electric dipole emission at 615 nm of the Eu3+ ions. Excitation spectra and lifetime measurements suggest that Eu3+ ions are incorporated at only one symmetry site. According to the crystal field theory, it is assumed that Eu3+ ions participate at octahedral sites of Zn2+ or Sn4+ under a weak crystal field, rather than at the tetrahedral sites of Zn2+, because of the high octahedral stabilization energy for Eu3+. Activation of symmetry forbidden (IR-active and silent) modes is observed in the Raman scattering spectra of both pure and doped samples, indicating a disorder of the cation sublattice of Zn2SnO4 nanocrystallites. These results were further supported by the first principle lattice dynamics calculations. The spinel-type Zn2SnO4 shows effectiveness in hosting Eu3+ ions, which could be used as a prospective green/red emitter. This work also illustrates how sustainable and simple preparation methods could be used for effective engineering of material properties.