Photoluminescence characteristics of rare earth-doped nanoporous aluminum oxide W.M. de Azevedo a,* , D.D. de Carvalho a , E.A. de Vasconcelos b , E.F. da Silva Jr. b a Departamento de Quı ´mica Fundamental, Universidade Federal de Pernambuco, Cidade Universita ´ria, Recife-PE 50670-901, Brazil b Departamento de Fı ´sica, Universidade Federal de Pernambuco, Cidade Universita ´ria, Recife-PE 50670-901, Brazil Available online 6 July 2004 Abstract In this work we present photoluminescence characterization of rare earth ion-doped nanoporous aluminum oxide synthesized by the anodization process in diverse solvents. We find that the luminescence of doped aluminum oxide strongly depends on the synthesis medium. When synthesized in an inorganic acid only rare earth fluorescence is present, whereas nanoporous aluminum oxide synthesized in organic solvent presents two strong unexpected luminescence emission lines, one at 429 nm and the other at 491 nm, with quite long decay time when excited with long wavelength ultraviolet light. The results suggest that light simulation of primary colors and chromaticity control of the emitted light can be done by the a combination of different rare earth ions present in the sample. # 2004 Elsevier B.V. All rights reserved. Keywords: Rare earth; Nanoporous; Luminescence; Aluminum oxide 1. Introduction Nanotechnology research, to a great extent is based on fabricating functional nanoscale structures and devices in a well-controlled way, which represents one of the most difficult challenges facing today’s researchers and engineers. The means to organize nanoelements into device structures in order to realize their desired functionalities, using inexpensive fabri- cation techniques, is essential from a technological point of view. Due to the small dimensions of these nanoelements, a bottom-up self-assembly process often provides a viable approach to overcome such technological challenges [1,2]. One of the important aspects of self-assembly lies in its capability of form- ing a large area of uniform structures through inex- pensive chemical or biological processes. A major concern of using self-assembly processes to fabricate nanoscale devices for electronic or optoelectronic applications is their compatibility with high-vacuum and high-temperature technologies. Most electronic and optoelectronic devices are based on high-quality semiconductors, and their production involves com- plicated micro or nanofabrication processes. It will be highly beneficial if the self-assembly nanofabrication techniques can be combined with traditional silicon microfabrication technologies in the pursuit of next- generation high-performance nanoscale devices. Aluminum anodization [3] is one of the most con- trollable self-assembly processes, and nanoporous Applied Surface Science 234 (2004) 457–461 * Corresponding author. Tel.: þ55 81 21268440; fax: þ55 81 21268442. E-mail address: wma@ufpe.br (W.M. de Azevedo). 0169-4332/$ – see front matter # 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.apsusc.2004.05.147