Keywords: hydrothermal synthesis, barium zirconate, nanocrystalline BaZrO3, upconversion emission, ytterbium, erbium, band gap, luminescence, sodium hydroxide, NaOH, nanotechnology
NaOH–controlled upconversion of nanocrystalline BaZrO3:Er,Yb phosphor
Strong green and red upconversion emissions of Er3+ in nanocrystalline BaZrO3:Yb,Er are observed. Powder samples were obtained by a simple hydrothermal process at 100°C under different NaOH molar concentrations and annealed in air at 1000°C for 3 h. Band gap and luminescence depend on precipitant molar concentration. Faceted single–phase BaZrO3 secondary particles were obtained for precipitant concentrations of 1.0 M, whereas for other precipitant concentrations, ZrO2 segregation was observed.