molybdenum trioxide

Background: With the spread of nanotechnology, various nanoparticles with new and emerging properties have been produced and the potential toxic effects of the majority of these particles remains still unknown. The present study was conducted to determine the toxicity of Molybdenum Trioxide nanoparticles in blood and body tissues of male Wistar rats.
Materials and Methods: Thirty Wistar rats with an average weight of 200±10 g were included in the present experimental study; the rats were divided into three groups of control, low dose intervention and high dose intervention. Nano-trioxide molybdenum was injected at 5 and 10 mg/kg body weight for 28 days; then, blood samples and rats organs were collected to measure the molybdenum content. Molybdenum concentration was measured by atomic absorption method. The collected data were analyzed using SPSS (Version 20) and appropriate statistical methods including one-way ANOVA were used in order to compare the mean of blood variables among the groups.
Results: The results showed that decreasing hematocrit (p <0.001), hemoglobin (p <0.001), and red and white blood cells (p <0.01) in rates receiving 10 mg of Molybdenum trioxide nanoparticles was significantly higher than that among rates in the other two groups. The mean degradation of molybdenum trioxide nanoparticles in the liver and kidneys was significantly higher than the heart and stomach (p <0.05).
Conclusion: The results of the study showed that molybdenum trioxide nanoparticles at high concentrations had a more toxic effect on blood and serum parameters in comparison with the low concentrations.

We have demonstrated a simple, low cost and swift method to prepare vertically aligned hexagonal MoO 3 nanorods on substrates using microwave irradiation. Most interestingly, the hexagonal rods can be converted to layered α-MoO 3 keeping the vertical alignment intact. In the present scenario, materials with specific length scales on the order of nanometers attract immense interest because of their potential application in both the scientific and the industrial world. Nanomaterials with a specific structure, order and orientation are the subject of research and product development because they could be potentially applied to macroscopic devices owing to their catalytic, magnetic, optical, semiconductor, or other superior properties. 1 Numerous approaches have been reported for the preparation of these micro-nano structures, viz., hydrothermal, physical and chemical vapour deposition, electron and laser beam induced deposition, microwave (MW) irradiation, etc. 2,3 Even though the hydrothermal method is one of the most extensively employed solution-based chemical methods for the synthesis of a host of nanostructured materials, the reaction times are longer. MW assisted synthesis of nanostructured systems has been extensively employed in recent times 4-6 following the pioneering work on organic synthesis. 7,8 The main advantage of MW assisted synthesis is the reduced time consumption from several hours to several minutes or even seconds ! 9 In addition to the faster reaction time, it has various advantages such as eco-friendliness, cost-effectiveness, rapid heating, increased reaction kinetics and higher product yields amongst many others. Transition metal oxides are well known for their catalytic activity and semiconducting nature. 10,11 MoO 3 is a promising functional material with a direct bandgap of 2.8-3.6 eV. 12 MoO 3 based systems have found diverse applications in cataly-sis, field emitting diodes, sensors, batteries, fuel cells, photo and electro-catalysts, and photo-chromic and electro-chromic devices owing to their structure, size and shape dependent material properties. 13-16 Crystalline MoO 3 is reported to have three polymorphs: orthorhombic (α-MoO 3-thermodynamically stable), monoclinic (β-MoO 3-metastable) and hexagonal (h-MoO 3-metastable) phases. 13 Orthorhombic α-MoO 3 consists of stacked bilayer sheets of MoO 6 octahedra held by van der Waals forces. It has a highly anisotropic layered structure along the [010] direction. On the other hand, hexagonal h-MoO 3 possesses large one-dimensional (1D) tunnels along the [001] direction , having zigzag chains of [MoO 6 ] octahedra as the building blocks interlinked through the cis-position. Even though α-MoO 3 is the thermodynamically stable form, the tunnel structure of h-MoO 3 gives an added effect for electron-hole separation under light irradiation. This factor enhances the catalytic activity of h-MoO 3 compared with α-MoO 3. 12 In this work, we have studied the synthesis and morphology of uniform, vertically aligned h-MoO 3 nanorods (NRs) on rigid substrates by MW irradiation using ammonium heptamolybdate (AHM) and concentrated nitric acid as the precursors. The vertical alignment of the nanorods results in structural anisotropy and is preferred for device fabrication as transport through oriented structures can be well understood. Charge transport through aligned metal oxide nanorods is more efficient due to less scattering and it also enables addressability of such arrays. This has been well documented in the case of vertically aligned nanostructures of ZnO and TiO 2 , which are widely employed in photovoltaics and piezotronics. 17,18 In the present study, vertically oriented nanorods are obtained on seeded substrates within 90 s by MW irradiation. Although there are numerous reports on the preparation of h-MoO 3 NRs even via MW synthesis, this is the first report on the MW assisted vertically aligned growth of MoO 3 NRs to the best of our knowledge. 19-21 The effect of MW power on the crystal structure and morphology of the NRs was initially studied in the solution 6568 | CrystEngComm, 2017, 19, 6568-6572 This journal is