Tin–oxide nanoparticles with controlled narrow size distributions are synthesized while physically encapsulated inside silica mesoporous templates. By means of ultraviolet-visible spectroscopy, a redshift of the optical absorbance edge is observed. Photoluminescence measurements corroborate the existence of an optical transition at 3.2 eV. The associated band of states in the semiconductor gap ...

Understanding the detailed electronic structure of deep defect states in narrow band-gap semiconductors has been a challenging problem. Recently, self-consistent ab initio calculations within density functional theory using supercell models have been successful in tackling this problem. In this paper, we carry out such calculations in PbTe, a well-known narrow band-gap semiconductor, for a larg...

Since the discovery of mesostructured materials in the early 1990s a great deal of effort has been devoted to developing new structures, compositions, and functionalities. The ability to synthesize semiconducting singleor multicomponent metal-oxide mesostructured materials with controlled morphologies has been a major step towards functional materials with potential applications in sensing, cat...