Defect and dopant induced photoluminescence of molten salt synthesized BaZrO3 crystals

Determining the Atomic Arrangement near the Oxygen Vacancy in Yttrium-Doped Barium Zirconate by Photoluminescence Spectroscopy

“…Since the electrotonic levels of oxygen vacancies in zirconia are dominated by the surrounding Zr 4d orbitals, which allow us to distinguish whether or not Zr is adjacent to the oxygen vacancies from the PL spectrum, such information of atomic arrangements helps us to understand the ionic transport influence by the dopants. The situation is almost the same in BaZrO 3 ; the electronic state of an oxygen vacancy in BaZrO 3 is also governed by the Zr 4d orbitals of the ZrO 6 octahedra. , The PL spectra of BaZrO 3 have been discussed with respect to the application as a luminescent material, − and the reported PL spectra showed a strong dependence on the defect type, defect density, and the environment . Thus, we consider that PL measurements can be used to characterize the atomic arrangement around oxygen vacancies in doped BaZrO 3 .…”

“…Note that a similar broad PL band has also been reported for undoped BaZrO 3 powders 28,31 and nanoparticles. 33 It has been pointed out that F + -centers, that is, oxygen vacancies with single unpaired electrons, are present in these materials. 29,35 We verified the presence of F + -centers in our samples by ESR, and Figure 4a shows the X-band ESR spectra at room temperature.…”

3D‐Architected Alkaline‐Earth Perovskites

“…[51,[62][63][64][65] The assignments of particular peaks in literature are often divergent and may differ depending on the synthesis method, particle morphology, size (e.g., nanometric or micrometric size), or crystallinity. [62] The emission ≈1.6-1.7 eV was previously assigned to the V O in HfO 2 , Hf 4+ , or other transition elements, which trace amounts are often found in ZrO 2 . [66,67]…”

Color tunable aerogels/sponge-like structures developed from fine fiber membranes

“…The same observation is true for the pure red emitting aerogel where the bright red emission band at 695 nm is ascribed to the 2 E -4 A 2 transition due to trivalent chromium ions occupying the octahedral sites within the red nanoparticles. 33,47,48 No fluorescence quenching of the fibers is observed due to the aerogel formation, rather the freeze-drying process removes the hydration from the structure which eliminates the chance of quenching. Moreover, the aerogels show higher emission intensities than fiber mats (Fig.…”