Molybdenum selenides

Chandra S, Sahu SNJ (1984) Electrodeposited semiconducting molybdenum selenide films. 1. Preparatory technique and stractural characterization. J Phys D Appl Phys 17 2115-2123 Dukstiene N, Kazancev K, Prosicevas 1, Guobiene A (2004) Electrodeposition of Mo-Se thin films from a sulfamatic electrolyte. J SoUd State Electrochem 8 330-336 Ponomarev EA, Neumann-SpaUart M, Hodes G, Levy-Qement C (1996) Electrochemical deposition of M0S2 thin films by reduction of tetrathiomolybdate. Thin SoUd EUms 280 86-89... 

Pig. 10-18. (a) PolarizatioD curves of anodic dissolution and (b) Mott-Schottky plots of an n-type semiconductor electrode of molybdenum selenide in the dark and in a photo-excited state in an acidic solution C = electrode capacity (iph) = anodic dissolution current immediately after photoexdtation (dashed curve) ipb = anodic dissolution current in a photostationary state (solid curve) luph) = flat band potential in a photostationary state. [From McEv( -Etman-Memming, 1985.]... 

Molybdenum selenide and molybdenum sulfide electrodes shall demonstrate the influence of different surface orientation on photoredox reactions. Figure U represents the crystal structure of MoS where one can immediately see that on the van der Waals-sur-face exclusively sulfur atoms are exposed to the contact with the electrolyte. They should behave very differently from any other surface where the molybdenum atoms are not so well shielded from interaction with the electrolyte solution. 

Photocurrent voltage curves have been studied with molybdenum selenide crystals of different orientation and different pretreatment. Figure 5 represents results for three typical surfaces of n-type MoSe (JJ+). An electrode with a very smooth surface cleaved parallel to the van der Waals-plane shows a very low dark current in contact with the KI containing electrolyte since iodide cannot directly inject electrons into the conduction band and can only be oxidized by holes. At a bias positive from the flat band potential U where a depletion layer is formed a photocurrent can be observed as shown in this Figure. This photocurrent reaches a saturation at a potential about 300 mV more positive than when surface recombination becomes negligible. 

Molybdenum Selenide.—On addition of mineral acids to solutions of molybdates through which hydrogen selenide has been passed, a brown precipitate of indefinite composition, but containing molybdenum selenide, is obtained. ... 

Se chemical shifts span a wide range of ca. 3300 ppm the extremes are marked by selenoaldehydes, some molybdenum selenides, and cationic heterocycles (up to S = 2434) at the high-frequency end and bridging selenium (p) in tungsten complexes (3 = —900) at the low-frequency end. A detailed discussion of electronic influences on Se chemical shifts and its variation in different classes of compounds has been published. In the following, some general characteristic tendencies are collected. 

Canfield D. and Parkinson B. A. (1981), Improvement of energy conversion efficiency by specific chemical treatments of molybdenum selenide (n-MoSei) and tungsten selenide (n-WSci) photoanodes , J. Am. Chem. Soc. 103, 1279-81. 

Ammonium sulphide) Barium sulphide Calcium sulphide Chromium (II) sulphide Copper (II) sulphide Diantimony trisulphide Dibismuth trisulphide Dicaesium selenide Dicerium trisulphide Digold trisulphide Europium (II) sulphide Germanium (II) sulphide Iron disulphide Iron (II) sulphide Manganese (II) sulphide Mercury (II) sulphide Molybdenum (IV) sulphide... 

Chromium(III) sulfide, CrySs chromium selenide, CrSe chromium(III) telluride, Cr2Tc3 molybdenum(IV) sulfide, M0S2 (molybdenite) molybde-num(IV) selenide, MoSe2 molybdenum(IV) telluride, MoTey tungsten(IV) sulfide,... 

Alonso-Vante N, Cattarin S, Musiani M. 2000. Electrocatalysis of O2 reduction at polyaniline + molybdenum-doped mthenium selenide composite electrodes. J Electroanal Chem 481 200-207. 

R. E. McCarley No, we have done very little work along this line, although I think important results will be obtained from studies of mixed 0, S phases. So far we have found no direct structural analogies between the reduced ternary molybdenum oxide phases and the various ternary sulfide or selenide phases of the Chevrel type. 

Bis-3,4-(trifluoromethyl)-l,2-diselenete 651 is prepared by refluxing selenium with hexafluoro-2-butyne. It reacts with triphenylphosphine and triphenyl-arsine. Triphenylphosphine selenide was isolated, but no other compounds were identified.Ring-opened complexes with nickel, copper, vanadium, molybdenum (652), tungsten, iron, and cobalt are analogous to complexes of the 1,2-dithiete (527) (Section XXXV.2.C.). 

Water-free inorganic solvents, such as ammonia, sulfur dioxide, and hydrazine, have been tested in terms of their suitability for electrolytic metal deposition. Liquid ammonia is used for a series of electrolytic metal deposition processes. Besides the low boiling point (- 33 °C) of this solvent its toxicity is disadvantageous. It has been reported that group lA and IIA metals, such as hthium, sodium, magnesium, and beryllium can be deposited from solutions based on ammonia as a solvent [45]. However, only thin or incoherent layers are thus produced [43, 44]. Because it is possible to form anions of molybdenum, lead, selenium, and tellmium in anunonia, these elements can be anodically deposited. Thus, deposition of the semiconductor lead selenide has also been achieved with ammonia as a solvent. 

Limonene cfr-epoxide (549) is favored by employing molybdenum-catalyzed epoxidation of limonene, and it undergoes franj-diaxial opening with sodium phenylselenide. Both the ring-opened selenides were readily converted to trans-... 

---