Chalcogenides material

The wide use of p-block and early transition metal chalcogenide materials for electronics applications (semiconductors, semi-metals, battery materials, etc.) has resulted in a large amount of work concerned with CVD using mixtures of metal halides and chalcogenoethers as dual source precursors and preformed complexes as single sources.166... 

Bochmann M (1996) Metal chalcogenide materials, Chalcogenolato complexes as singlesource precursors. Chemical Vapor Deposition 2(3), 85-97... 

Physico-Chemical Properties of Novel Nanocrystalline Ruthenium Based Chalcogenide Materials... 

As an example, Fig. 5.6 depicts a typical diffraction spectrum. It is evident that long range order does not exist in our chalcogenide samples. However, the broad difffactrogram peak centered at 20 = 42.5° has the characteristic of a nanodivided ruthenium metal [22]. This points out that the active center in this chalcogenide materials is essentially of metallic nature. The material, either in powder or colloidal form, was analyzed by the EXAFS technique [11]. The local range order of this technique allowed for some structural determination of our samples. Thus, for example, the co-ordination distances for ruthenium-selenium and ruthenium-ruthenium are R(RU-se) = 2.43 A y R(ru.rU) = 2.64 A, respectively. The metal-metal co-ordination distance is of the same order of magnitude as that of well known cluster based materials such as the Chevrel phase [35, 37], cf. Fig. 5.2b. This testifies that the used chemical route leads to the formation of cluster-like materials. 

Electrocatalysis via Thin and ultra Thin Layers of Chalcogenide Materials... 

The novel cluster-like chalcogenide material RuxSey deposited in thin [5, 26, 31, 36] and ultra-thin layers [9, 11] or in powder form embedded in a polymer matrix [30] was found to be an efficient catalyst for the molecular oxygen reduction in acid medium. Fig. 5.10 summarizes the current-potential (j-E) characteristics as a function of the substrate s nature. First of all, one can appreciate that similar activities are obtained from materials synthesized in powder or in colloidal form when deposited onto GC (Fig. 5.10, compare curves (1) and (2)). For the sake of comparison, the j-E characteristic generated on the naked GC substrate for the electrochemical process is contrasted in curve (5). 

Photo)Electrocatalysis on Nanostructured TiO2 Surface Modified via Chalcogenide Materials... 

Similar face capped octahedral clusters are found in a family of chalcogenide materials called Chevrel phases - PbMo6S8 etc. 

Photoirradiation of this stacked film causes the Ag to diffuse into the Se-Ge film in a process referred to as Ag-photodoping. This diffusion, which is characteristic of amorphous chalcogenide materials, causes the Se-Ge film to become insoluble in alkaline solutions and the resist thus functions as a negative-type photoresist. The photodoped regions also are resistant to fluorine-based plasmas enabling dry development of the resist (7). Dry development has also been achieved using a reactive-ion etching (RIE) technique and is discussed later. 

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