Rapid Synthesis of Undoped and Er Doped MoO3 Layered Plates by Resistive Heating of Molybdenum: Structural and Optical Properties

Abstract

Resistive heating of molybdenum wires is used for the synthesis of alpha‐MoO3 layered nano‐ and microplates. A high density of MoO3 plates grow on the surface of the metallic wire in 2–3 min when an electric current density of the order of 104 Acm−2 flows through the Mo wire. During the current flow, a temperature gradient along the wire appears due to the heat dissipation at the electric contacts at both ends of the wire. The plates grow preferentially in the region heated at 450–500 °C. The synthesized MoO3 plates are characterized by micro Raman spectroscopy, scanning electron microscopy, electron backscatter diffraction, cathodoluminescence, and X‐ray photoelectron spectroscopy. In addition, this quick synthesis approach enables the doping of the nanoplates. Setting in contact the Mo wire with Er2O3 powders during the resistive heating, Er doping of the resulting MoO3 is achieved. The Er incorporation during growth is revealed in the cathodoluminescence spectra of the plates, which show the characteristic emission lines of Er3+ions. Diffusion mechanisms related to the very rapid and effective growth by resistive heating of the undoped and Er doped molybdenum oxide plates, as compared with other thermal methods, are discussed.