Optical and Electrical Properties of Eu³⁺-Doped SnO₂ Nanocrystals

Here, we report the preparation of pure and Eu 3+ -doped SnO 2 nanocrystals by microwave synthesis. The size dependence of the band gap energies of the quantum-confined SnO 2 particles agrees very well with the confinement regime. The PL intensity, decay time, and quantum efficiency are found to be sensitive to the particle size. The calculated quantum efficiencies are 22.0%, 31.0%, and 26.0% for 300, 400, and 800 °C heated samples, respectively, because minimum nonradiative decay rate is observed at 400 °C heated sample. Analysis suggests that the crystallite size plays an important role in tuning the quantum efficiency, emission intensity, and decay time of Eu 3+ -doped SnO 2 nanocrystals. Results show that the conductivity for doped sample is higher than that for pure SnO 2 nanocrystals and pure SnO 2 nanocrystals showed a typical rectifying behavior.