Premium
Dipole‐Induced Band‐Gap Reduction in an Inorganic Cage
Author(s) -
Lv Yaokang,
Cheng Jun,
Steiner Alexander,
Gan Lihua,
Wright Dominic S.
Publication year - 2014
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201307721
Subject(s) - dopant , band gap , doping , materials science , dipole , metal , cobalt , photocatalysis , absorption (acoustics) , nanotechnology , nanoparticle , chemical physics , inorganic chemistry , chemistry , optoelectronics , catalysis , organic chemistry , metallurgy , composite material
Metal‐doped polyoxotitanium cages are a developing class of inorganic compounds which can be regarded as nano‐ and sub‐nano sized molecular relatives of metal‐doped titania nanoparticles. These species can serve as models for the ways in which dopant metal ions can be incorporated into metal‐doped titania (TiO 2 ), a technologically important class of photocatalytic materials with broad applications in devices and pollution control. In this study a series of cobalt(II)‐containing cages in the size range ca. 0.7–1.3 nm have been synthesized and structurally characterized, allowing a coherent study of the factors affecting the band gaps in well‐defined metal‐doped model systems. Band structure calculations are consistent with experimental UV/Vis measurements of the Ti x O y absorption edges in these species and reveal that molecular dipole moment can have a profound effect on the band gap. The observation of a dipole‐induced band‐gap decrease mechanism provides a potentially general design strategy for the formation of low band‐gap inorganic cages.