Synthesis and processing of AgInO 2 delafossite compounds by cation exchange reactions

• Published in: Thin solid films Vol. 411; no. 1; pp. 140 - 146
• Main Authors: Clayton, Jane E, Cann, David P, Ashmore, Nathan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2002
• Subjects: Cation exchange reactions; Delafossite compounds; Silver indium oxide; Cation exchange reactions; Silver indium oxide; Delafossite compounds
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/S0040-6090(02)00203-1

In recent years, ternary noble metal oxide compounds based on the delafossite structure have attracted great interest because of their potential use as transparent conductors. In this work, the experimental conditions which affect the synthesis and properties of Ag-based compounds by the cation exchange technique was explored. The reaction between AgNO 3 and NaInO 2 was performed at temperatures ranging from 200 to 300 °C in air over a period of 48 h or more. With X-ray diffraction, the phase distribution and crystallite size was monitored and related to the experimental conditions. Electron microscopy was also utilized to observe the phase distribution and locate the presence of secondary phases such as Ag metal. From these results, it was concluded that the volume change associated with the NaInO 2 to AgInO 2 transformation affected the delafossite crystallite size. The effects of KNO 3 in promoting the cation exchange reaction were also discussed in terms of stabilizing the AgNO 3:NaNO 3:KNO 3 solution. Finally, it was shown that n-type AgInO 2 with a conductivity of 6 S cm −1 was synthesized by modifying the precursor NaInO 2 phase.