α-MoO3 Crystals with a Multilayer Stack Structure Obtained by Annealing from a Lamellar MoS2/g-C3N4 Nanohybrid

• Main Authors: Pablo Martín-Ramos, Ignacio A. Fernández-Coppel, Manuel Avella, Jesús Martín-Gil
• Format: Article
• Language: English
• Published: MDPI AG 2018-07-01
• Series: Nanomaterials
• Subjects: α-MoO3; carbon nitride; g-C3N4; molybdenum trioxide; nanoplates; synthesis
• Online Access: http://www.mdpi.com/2079-4991/8/7/559

Transition metal oxides and chalcogenides have recently attracted great attention as the next generation of 2-D materials due to their unique electronic and optical properties. In this study, a new procedure for the obtaining of highly crystalline α-MoO3 is proposed as an alternative to vapor-phase synthesis. In this approach, a first reaction between molybdate, citrate and thiourea allowed to obtain MoS2, which—upon calcination at a temperature of 650 °C in the presence of g-C3N4—resulted in MoO3 with a definite plate-like shape. The colorless (or greenish) α-MoO3 nanoplates obtained with this procedure featured a multilayer stack structure, with a side-length of 1–2 μm and a thickness of several nanometers viewed along the [010] direction. The nucleation-growth of the crystal can be explained by a two-dimensional layer-by-layer mechanism favored by g-C3N4 lamellar template.