Synthesis and Performance of BaAl 2 O 4 with a Wide Spectral Range of Optical Absorption
2007; Wiley; Volume: 17; Issue: 18 Linguagem: Inglês
10.1002/adfm.200700506
ISSN1616-3028
AutoresLiwu Zhang, Lai Wang, Yongfa Zhu,
Tópico(s)Layered Double Hydroxides Synthesis and Applications
ResumoAbstract Oxygen‐deficient BaAl 2 O 4 , with strong optical absorption in the spectra range from 200 to 2500 nm, was prepared by a simple and economic thermal treatment of BaAl 2 O 4 in a H 2 gas flow. Further studies found that a molar ratio of oxygen vacancies of about 0.4 % existed in the prepared oxygen‐deficient BaAl 2 O 4 sample. The influence of oxygen vacancies on the electronic band structures and optical absorption of BaAl 2 O 4 are elucidated via first principle calculations. Oxygen vacancies introduce impurity states above the valence band; these impurities expand and enhance the optical absorption of BaAl 2 O 4 . This approach is proposed to develop a new type of optical materials and to be applicable to many wide bandgap materials.
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