Spectroscopic Studies of Nd3+ Exchanged Beta' Alumina
Abstract
Sodium Beta and Beta' aluminas have long been known for their properties as solid electrolytes. The materials possess an anisotropic crystal structure which consists of spinel blocks of closely packed Al(3+) and O(2-) separated by loosely packed 'conduction planes' which contain the mobile ionic species (i.e., Na(+)) and O(2-). The fast ion transport properties of these materials are related to the nature of these planes. One other significant property, particularly for te Beta' aluminas, is their remarkable ion exchange behavior. Numerous divalent and trivalent ions exchange rapidly with sodium in Beta' alumina, enabling a wide range of divalent and trivalent Beta' alumina compositions to be synthesized. The ability to easily incorporate transition metal and lanthanide ions within Beta' alumina has led to the investigation of the optical behavior of ion exchanged Beta' aluminas. Optical absorption spectroscopy and Electron Spin Resonance (ESR) techniques were used to study the site occupations for Neodymium (3+) occupy mid-oxygen sites primarily. There is some population of the tetrahedral site, however, the concentration is too low to be clearly observed by ESR. Crystals which were completely exchanged (approx. 1.8x 10 to the 21st power Nd/cu. cm) exhibited rather different behavior. The spectroscopy results for these material indicate that there is a combination of both isolated Nd(3+) ions as well as discrete pairs.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1988
- Accession Number
- ADA197446
Entities
People
- Bruce S. Dunn
- D. L. Yang
- D. Vivien
Organizations
- University of California, Los Angeles