Synthesis, characterization and investigation of properties photoluminescent of MoO₃

Full text: Molybdenum trioxide (MoO₃ ) as one of the well-known n-type semiconductors is attractive due to its various potential applications in many fields, such as photochromic, electrochromic devices, sensors, catalysts and photoluminescence. Molybdenum trioxide exhibits new optical absorption bands after it is irradiated with UV-light. As we know, molybdenum trioxides have three forms: the well-known thermodynamically stable phase of α-MoO₃, metastable phases of β-MoO₃ and h-MoO₃ . The metastable structures often show some novel or enhanced properties compared to their thermodynamically stable forms, but their preparation are usually more difficult. MoO₃ nanocrystals were synthesized by HT method. Molybdate tetrahydrate ((NH₄ )₆Mo₇O₂₄·4H₂O), nitric acid (HNO₃ ) (v/v) and deionized water. All the XRD patters of MoO₃ nanocrystals can be indexed to the hexagonal structure with space group P63. Diffraction peaks related to the secondary phases were not detected, indicating the obtention of a monophasic system. The MoO₃ obtained by HT method present a hight intensity of PL emission. This behavior can be related to the greatest number of defects on the crystals formed by this method. References: [1] I. NAVAS, R. VINODKUMAR, P. MAHADEVAN. Self-assembly and photoluminescence of molybdenum oxide nanoparticles. Appl Phys A. 103(2011)373-380. [2] J. SONG, X. NI, D. ZHANG, H. ZHENG. Fabrication and photoluminescence properties of hexagonal MoO₃ rods. Solid State Sciences 8(2006)1164-1167. (author)