Photoluminescence of nanostructured PbTiO3 processed by high-energy mechanical milling

This letter reports on a process to prepare nanostructured PbTiO3 (PT) at r oom temperature with photoluminescence (PL) emission in the visible range. This process is based on the high-energy mechanical milling of ultrafine Pb TiO3 powder. The results suggest that high-energy mechanical milling modifi es the particle's structure, resulting in localized states in an interfacia l region between the crystalline PT and the amorphous PT. These localized s tates are believed to be responsible for the PL obtained with short milling times. When long milling times are employed, the amorphous phase that is f ormed causes PL behavior. An alternative method to process nanostructured w ide-band-gap semiconductors with active optical properties such as PL is de scribed in this letter. (C) 2001 American Institute of Physics.