Molybdenum oxides/bronzes

M. Greenblatt, Molybdenum oxide bronzes with quasi low-dimensional properties. Chem. Rev. 88 (1988) 31. 

Figure 3. SEM image of u sample of toroidal niesostruciured molybdenum oxide bronzes showing lack of any extended order in the structure.

Special mention must be given to the numerous studies concerning hydrogen bronze formation induced by spillover. In particular, tungsten and molybdenum oxide hydrogen bronzes have been thoroughly studied since Khoobiar s experiments (4). 

C. Schlenker ed., Low Dimensional Electronic Properties of Molybdenum Bronzes and Oxides , Kluwer, Dordrecht, 1989. 

C. Schlenker, J. Dumas, C. Escribe-FUippini, and H. Guyot, in Low Dimensional Electronic Properties of Molybdenum Bronzes and Oxides , ed. C. Schlenker Kluwer, Dordrecht, 1989, p. 159. 

Oxides of the type A O- (A = alkali metal) are known as tungsten oxide bronzes. These are readily prepared by the insertion of the alkali metal into WO3. The corresponding molybdenum bronzes are more difficult to prepare. High pressures and electrochemical methods are generally employed to synthesize some of them. A simple solid-state reaction between an alkali iodide and M0O3 or Moj j Wj 03 (under dry conditions) has been found to yield such molybdenum oxide bronzes [11]. The following reaction represents a simple means of making these bronzes ... 

Zinc oxide silicate Bronze Molybdenum disulfide... 

On the other side, there are efforts to use some bronzes as reference electrodes. Gabel et al. [191] who studied the behavior of several polycrystalline bronzes found that tungsten substituted lithium molybdenum oxide bronzes with general formula A cMoi yW3,03 may be applied as materials for solid-state reference electrodes. They found that the potential of such electrodes does not change significantly with the change of pH, sodium ion concentration, and redox potential of a studied solution. 

Method V - hydrogen molybdenum oxide bronze (HJMoO. This was demonstrated by Xie et al. to realize a one-step method to synthesize low-temperature solution-processed The ethanol used in synthesizing the... 

Based on the hydrogen molybdenum oxide bronze, Li et al. demonstrated high performance inverted OSCs by using solution-processed MoO. with unique features of room-temperature and water-free processing. By introducing the vacuum treatment after the deposition of the MoO film on the... 

Potassium Molybdenum Oxide Blue Bronze" Ko ioMoOj 119... 

POTASSIUM MOLYBDENUM OXIDE BLUE BRONZE K .3 Mo03... 

Potassium Molybdenum Oxide "Blue Bronze" K aMoOi 121... 

The reduction of molybdate salts in acidic solutions leads to the formation of the molybdenum blues (9). Reductants include dithionite, staimous ion, hydrazine, and ascorbate. The molybdenum blues are mixed-valence compounds where the blue color presumably arises from the intervalence Mo(V) — Mo(VI) electronic transition. These can be viewed as intermediate members of the class of mixed oxy hydroxides the end members of which are Mo(VI)02 and Mo(V)0(OH)2 [27845-91-6]. MoO and Mo(VI) solutions have been used as effective detectors of reductants because formation of the blue color can be monitored spectrophotometrically. The nonprotonic oxides of average oxidation state between V and VI are the molybdenum bronzes, known for their metallic luster and used in the formulation of bronze paints (see Paint). 

Only about 10 elements, ie, Cr, Ni, Zn, Sn, In, Ag, Cd, Au, Pb, and Rh, are commercially deposited from aqueous solutions, though alloy deposition such as Cu—Zn (brass), Cu—Sn (bronze), Pb—Sn (solder), Au—Co, Sn—Ni, and Ni—Fe (permalloy) raise this number somewhat. In addition, 10—15 other elements are electrodeposited ia small-scale specialty appHcations. Typically, electrodeposited materials are crystalline, but amorphous metal alloys may also be deposited. One such amorphous alloy is Ni—Cr—P. In some cases, chemical compounds can be electrodeposited at the cathode. For example, black chrome and black molybdenum electrodeposits, both metal oxide particles ia a metallic matrix, are used for decorative purposes and as selective solar thermal absorbers (19). 

In cases where very high adherence is necessary an undercoating of sprayed molybdenum is applied. Owing to the volatile nature of its oxide this metal presents a clean surface to the workface and with most metals (except copper) very high adhesion is obtained. To a limited extent arc-sprayed aluminium bronze will also form a strongly adherent base coating. 

A non-enzymatic color reaction for TATP and other organic peroxides was reported recently by Apblett et al. [87, 88]. The dark blue color of molybdenum hydrogen bronze suspension is changed to yellow upon oxidation with TATP. The same reagent can also be used for quick neutralization of the sensitive explosive a lasting final blue color indicates complete neutralization. The reaction with TATP is depicted in Eq. (13). 

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