Reduction characteristics of molybdenum trioxide with aluminum and silicon

Abstract

Thermodynamics for reduction of molybdenum oxides by aluminum and silicon were calculated, and the results show that reduction reaction is feasible at a certain temperature region. Compared to the presence of CaO or CaCO 3 , reduction products of molybdenum trioxide with aluminum and silicon at various temperatures were detected by X-ray diffraction (XRD). Results show that molybdenum trioxide is reduced by aluminum or silicon step by step, and the intermediate product is MoO 2 . At 1000°C, molybdenum trioxide could be reduced to metal Mo by aluminum, and in the presence of CaO, metal Mo as the reduction product appears even at 800°C. In contrast, silicon could barely reduce molybdenum trioxide to metal Mo even at 1200°C. In the presence of CaO or CaCO 3 , reducibility of silicon increases significantly, and the reduction products are metal Mo and MoSi 2 . Altogether, CaO or CaCO 3 performs two major roles in reduction process: restraining sublimation of MoO 3 and decreasing the temperature of reducing MoO 3 to metal Mo.

In Situ Transmission Electron Microscopy Study of Molybdenum Oxide Contacts for Silicon Solar Cells

“…Furthermore, HRTEM images further revealed the presence of an AlO x interlayer at the MoO x /Al interface in the as‐deposited state (Figure a). This can be attributed to favorable thermodynamic conditions . The higher oxygen affinity of Al compared to Mo is the driving force for oxygen diffusion from MoO x toward Al resulting in the formation of AlO x interlayer as well as creation of defect states within MoO x layer.…”

In Situ Transmission Electron Microscopy: A Powerful Tool for the Characterization of Carrier-Selective Contacts

“…This can be attributed to favorable thermodynamic conditions. [23] The higher oxygen affinity of Al compared to Mo is the driving force for oxygen diffusion from MoOx towards Al resulting in the formation of AlOx interlayer as well as creation of defect states within MoOx layer. When the annealing temperature is increased to 200°C, AlOx and MoOx layers are clearly distinguishable which indicates that no major change occurs at MoOx/AlOx interface.…”

Effects of ammonium molybdate additive and sintering temperature on the properties of foam ceramics based on ceramic tile polishing waste

“…The weight loss in sample S2 was less than that in sample S0, which indicated that the sublimation of MoO 3 obtained from decomposition of (NH 4 ) 6 Mo 7 O 24 was not happened and may be restrained by the existence of CaO or CaCO 3 in CTPW. 32), 33) In addition, the initial temperature of weight increment (about 1000°C) that may be the starting temperature of SiC oxidation reaction in sample S2 were lower than that in sample S0. This variation showed that the MoO 3 (like alkali metal oxide or alkali earth metal oxide) could promote the formation of liquid phase in a lower temperature.…”