Experimental and theoretical correlation of very intense visible green photoluminescence in BaZrO3 powders

Abstract

Very intense visible green photoluminescence ͑PL͒ was observed at room temperature in structurally ordered-disordered BaZrO 3 powders. Ab initio calculations, ultraviolet-visible absorption spectroscopy, electron paramagnetic resonance, and PL were performed. Theoretical and experimental results showed that local defects in the cubic structure caused byplay an important role in the formation of hole-electron pairs, giving rise to a charge gradient in the structure which is responsible for PL emission.

Cathodoluminescence characterization of polystyrene-BaZrO3 hybrid composites

“…The respective Gaussian decomposition into three possible bands A, B, C is also presented. This spectrum is similar to PL emission profile [16,17] and is typical for multiphonon and multilevel process, i.e., a system in which the electronic relaxation occurs by several paths, including numerous energy levels within the band gap [7]. According to [16][17][18][19][20]26] Figure 2 illustrates CL spectra of nano-BZO samples, both as prepared and annealed during 2 h at different temperatures (up to 800 °C).…”

“…This spectrum is similar to PL emission profile [16,17] and is typical for multiphonon and multilevel process, i.e., a system in which the electronic relaxation occurs by several paths, including numerous energy levels within the band gap [7]. According to [16][17][18][19][20]26] Figure 2 illustrates CL spectra of nano-BZO samples, both as prepared and annealed during 2 h at different temperatures (up to 800 °C). These results demonstrate hightemperature stability of CL intensity and spectral composition, contrary to the results published earlier [16][17][18][19][20]26].…”

“…According to [16][17][18][19][20]26] Figure 2 illustrates CL spectra of nano-BZO samples, both as prepared and annealed during 2 h at different temperatures (up to 800 °C). These results demonstrate hightemperature stability of CL intensity and spectral composition, contrary to the results published earlier [16][17][18][19][20]26]. This behavior is attributed to micro-BZO (d < 10 μm) powders.…”

“…Since recently it also attracts a considerable attention as a fluorescent material. It is well known that the luminescent characteristics of BZO significantly depend on fabrication technology of micro-and nanocrystals; using different technological routes, samples can be tailored to show violet, blue, green or red luminescence [7,8,[16][17][18][19][20].…”

Fingerprints of short-range and long-range structure in BaZr1−xHfxO3 solid solutions: an experimental and theoretical study

“…This material is chemically and thermally stable 4,5 , as well as their optical properties were observed under different circumstances, since quasi-amorphous compounds 6 through quasi-crystalline systems 6,7 and finally to periodic crystals 8,9 . BZO presents cubic perovskite sym- metry with ZrO 6 octahedral and BaO 12 cubooctahedral clusters.…”