Thermal Stability, Optical and Electrical Properties of Substoichiometric Molybdenum Oxide

Substoichiometric molybdenum oxide ceramics have aroused widespread interest owing to their promising optical and electrical performance. In this work, the thermal stability and decomposition mechanism of Mo(9)O(26) and Mo(4)O(11) at 700–1000 °C and 700–1100 °C were investigated, respectively. Based on this information, MoO(x) (2 < x < 3) bulk ceramics were prepared by spark plasma sintering (SPS). The results show that Mo(9)O(26) is stable up to 790 °C in an argon atmosphere. As the temperature rises, it decomposes into Mo(4)O(11). Mo(4)O(11) can exist stably at 830 °C, beyond which it will convert to MoO(2). The MoO(x) ceramic bulks with four different components (MoO(2.9), MoO(2.8), MoO(2.7) and MoO(2.6)) were successfully sintered by SPS, and their relative density was greater than 96.4% as measured by the Archimedes principle. The reflectivity of MoO(x) ceramic bulk is low and only 6.3% when the composition is MoO(2.8). The resistivity increases from 10(−3) to 10(−1) Ωcm with the increase in the O/Mo atomic ratio x. In general, the thermal stability information provides a theoretical basis for the processing of MoO(x) materials, such as the sintering of the MoO(x) target. The optical and electrical properties show that MoO(x) is a low-reflective conductive oxide material with great photoelectric application value.