Molybdenum disulphide (MoS2) has been one of the most interesting materials for scientists and engineers for a long time. While its bulk form has been in use in conventional industries as an intercalation agent and a dry lubricant for many years, its two-dimensional forms have attracted growing attention in recent years for applications in nano-electronic applications. Specifically, the single layer form of MoS2 shows significant potential as a semiconductor analogue of graphene. These exciting applications are spread over many fields, from flexible and transparent transistor devices, to low-power, high efficiency biological and chemical sensing applications. This Review Article, for the first time, provides a comprehensive overview of the synthesis, structural polytypes, properties, and applications of bulk, few layer, and single layer MoS2.

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Synthesis and properties of molybdenum disulphide: from bulk to atomic layers

https://estudogeral.sib.uc.pt/bitstream/10316/5452/1/file03600a734caa4782ab96e0085c0310b5.pdf

Toxicity of Sodium Molybdate and Sodium Dichromate to Daphnia magna Straus Evaluated in Acute, Chronic, and Acetylcholinesterase Inhibition Tests

Mo is an essential trace element for both plants and animals in low concentrations (<5 ppm). However, provoked by uncontrolled industrial waste releases in freshwater or seawater, it is plausible that excessive availability of soluble Mo(VI) would be potentially toxic. In the environment, soluble Mo(VI) is mainly present in anionic forms of molybdate (MoO4 2−) and/or tetrathiomolybdate (MoS4 2−). The fate and transport of soluble Mo(VI) anions in surface and subsurface aquatic environments is typically controlled by adsorption in acidic soils and sediment. As such, the ability of soils/bed sediments to retain Mo(VI) is a key to determine its general mobility in the aquatic environment. This article reviews the sources and distribution of Mo speciation in solution and Mo(VI) anions adsorption mechanisms in soils and bed sediments, and evaluates the surface adsorption complexation models at the solid-water interface to estimate Mo(VI) anions adsorption in these chemical systems. Mo(VI) anions adsorption mec...

A Review of Molybdenum Adsorption in Soils/Bed Sediments: Speciation, Mechanism, and Model Applications

The thermal behavior of ammonium molybdates, i.e., (NH4)6Mo7O24·4H2O (1) and (NH4)2MoO4 (2), was studied in inert (N2) and oxidizing (air) atmospheres by TG/DTA-MS, XRD, FTIR and SEM. The thermal decomposition sequence of 2 had similarities to 1; however, there were significant differences as well. When both of them were annealed, NH3 and H2O were released parallel, and in air the as-evolved NH3 was burnt partially into NO and N2O. In both atmospheres, while 1 decomposed in four steps, the thermal decomposition of 2 involved 5 steps. In the case of 1, the intermediate products were (NH4)8Mo10O34, (NH4)2Mo4O13 and h-MoO3. In contrast, the decomposition intermediates of 2 were (NH4)2Mo3O10, (NH4)2Mo2O7, (NH4)2Mo4O13 and h-MoO3. By both 1 and 2, the final product was dominated by o-MoO3, accompanied with small amount of Mo4O11 in N2, which was absent in air. Most decomposition steps were endothermic, except for the last step around 400 °C, where crystallization from the residual amorphous phase had an exothermic heat effect. In addition, the combustion of NH3 also changed the DTA curve into exothermic in some cases. The morphology of the final products was characterized by 1–5 μm sheet-like particles, except for annealing 2 in N2, when 0.5- to 1-μm-thick and 5- to 10-μm-long needle-shaped particles were detected.

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Thermal decomposition of ammonium molybdates

MoS2 supported on P25 titania: A model system for the activation of a HDS catalyst

The article contains sections titled:



1.	Introduction	
2.	Properties	
3.	Occurrence	
3.1.	Minerals	
3.2.	Deposits	
4.	Production	
4.1.	Concentration	
4.2.	Processing of Concentrate	
4.3.	Recovery from Spent Petroleum Catalysts	
4.4.	Recovery during Production of Tungsten Ores	
4.5.	Production of Molybdenum Metal Powder	
4.6.	Production of Compact Molybdenum Metal	
4.7.	Processing of Molybdenum	
4.8.	Molybdenum-Base Alloys	
5.	Uses	
6.	Production of Ferromolybdenum	
6.1.	Ferromolybdenum Grades	
6.2.	Raw Materials	
6.3.	Submerged Arc Furnace Carbothermic Reduction	
6.4.	Metallothermic Reduction	
7.	Molybdenum Compounds	
7.1.	Overview of Molybdenum Chemistry	
7.2.	Molybdenum Oxides	
7.3.	Molybdenum Chalcogenides	
7.4.	Molybdenum Halides	
7.5.	Molybdates, Isopolymolybdates, and Heteropolymolybdates	
7.6.	Other Molybdenum Compounds	
8.	Uses of Molybdenum Compounds	
8.1.	Catalysis	
8.2.	Lubrication	
8.3.	Corrosion Inhibition	
8.4.	Flame Retardancy and Smoke Suppression	
8.5.	Pigments	
8.6.	Agriculture	
9.	Analysis	
10.	Economic Aspects	
11.	Environmental Aspects	
12.	Toxicology and Occupational Health

Douglas A. Church

Papers

Molybdenum and Molybdenum Compounds