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| Section2 = | Section3 = }} Silver molybdate (Ag2MoO4) presents two types of electronic structure, depending on the pressure conditions in which the crystal is subjected. At room temperature, Ag2MoO4 exhibits a spinel-type cubic structure related to beta (β-Ag2MoO4) phase, which is more stable in nature. However, when exposed to high hydrostatic pressure, these crystals have a tetragonal structure associated to alpha (α-Ag2MoO4) metastable phase. Recently, the literature has reported the formation of α-Ag2MoO4 metastable phase by the solution-phase precipitation method under environment condition, and using 3-bis(2-pyridyl)pyrazine (dpp) as doping. The influence of pH at starting solution on the growth and formation processes of distinct heterostructures (brooms, flowers and rods) was investigated by Singh ''et al''. and Fodjo ''et al''., in which the sodium borohydride was employed to induce the reduction of silver nanoparticles on the surface of Ag2MoO4 crystals in order to enhance the Raman scattering. In other studies, Ag-Ag2MoO4 composites prepared by microwave-assisted hydrothermal synthesis presented interesting photocatalytic activity for the degradation of Rhodamine B under visible light. In addition, Ag2MoO4 mixed with graphite acts as a good lubricant for Ni-based composites, improving the tribological properties of this system. Different synthesis methods have been employed to obtain pure β-Ag2MoO4 crystals, including solid-state reaction or oxide mixture at high temperature, melt-quenching and Czochralski growth. Particularly, high temperatures, long processing times, and/or sophisticated equipment are necessary in these synthetic routes. Moreover, the final products may be composed of irregular particle shapes with nonhomogeneous size distribution as well as contain the presence of secondary phases. In recent years, pure β-Ag2MoO4 crystals have been synthesized by the co-precipitation, microwave-assisted hydrothermal synthesis,〔 dynamic template route using polymerization of the acrylamide assisted templates and impregnation/calcination method. Recentely, the literature have reported the formation of β-Ag2MoO4 crystals using different chemical solvents in the reaction medium. These β- Ag2MoO4 microcrystals were synthesized by the precipitation method, employing several polar solvents: deionized water (H2O), methanol (CH4O), ethanol (C2H6O), 1-propanol (C3H8O) and 1-butanol (C4H10O) at 60oC for 8 h. X-ray diffraction (XRD), Rietveld refinements and field emission scanning electron microscopy (FESEM) were employed in structural and morphological characterizations. A schematic representation of a β-Ag2MoO4 structure modeled by means of Rietveld refinement data is illustrated below: https://photos.google.com/album/AF1QipMDxzPdU5M9hzKMkJEE-GDVYrDFnS50MHMPSAOe/photo/AF1QipMf9YfsTzQJtcP7YZLt4Ca1CFLzYgmFQjPWaot4?key=CMbW68ma-I-N_gE ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Silver molybdate」の詳細全文を読む スポンサード リンク
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