Micro-Raman study of the m-MoO2 to α-MoO3 transformation induced by cw-laser irradiation

✍ Scribed by M.A. Camacho-López; L. Escobar-Alarcón; M. Picquart; R. Arroyo; G. Córdoba; E. Haro-Poniatowski

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 473 KB
• Volume: 33
• Category: Article
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2010.10.028

✦ Synopsis

In this work we report the monoclinic-MoO 2 to orthorhombic-MoO 3 transformation induced by continuous wave-laser irradiation. A Helium-Neon laser was used as energy source. The transformation involved two processes: an initial oxidation followed by a transition from a crystalline phase (MoO 2 ) to the other (MoO 3 ). Both processes, oxidation and structural changes, were monitored in situ by micro-Raman spectroscopy. Structural transformations were analyzed as a function of the laser power and as a function of the exposure time (transformation kinetics). Under these low power irradiation conditions it was found that the monoclinic-MoO 2 transforms completely to the well-known orthorhombic phase a-MoO 3 in a few minutes.