Soft chemistry

At the start of this Chapter, an essay by Peter Day was quoted in which he lauds the use of soft chemistry , exemplifying this by citing the use of organometallic precursors for making thin films of various materials used in microelectronics. The same approach, but without the softness, is increasingly used to make ceramic fibres here, ceramic includes carbon (sometimes regarded as almost an independent state of matter because it is found in so many forms). 

J J. O. Besenhard, in Soft Chemistry Routes to New Materials (Eds. J. Rouxel, M. Toumoux, R. Brec), Materials Science Volumes 152-153, Trans-Tech Publications, Switzerland, 1994, p. 13. 

A broader and more important implication of the oxychlorides is the potential of expanding the ligand combination to other transition-metal cluster systems. The advances in soft-chemistry techniques open up new possibilities for the sta-... 

Long et al. reported the synthesis of tungsten oxychloride clusters via a soft-chemistry route [60], which confirms the potential for wide applications of the ligand combination strategy in cluster chemistry. 

Metal chalcogenides, apart from their technological significance in industrial applications, have played an important role in the development of new synthetic concepts and methods in the area of solid-state chemistry. A great example is alkali metal intercalation into TiS2 (Chap. 6) first reported three decades ago, which highlighted the then-novel synthetic approach called soft chemistry chimie douce). This low-temperature process allows for new compounds to be obtained while retaining the structural framework of the precursor. Related to this concept is the... 

Julien, C., Letranchant, C., Rangan, S., Lemal, M., Ziolkiewicz, S., Castro-Garcia, S., El-Farh, L., Benkaddour, M., Layered LiNi0j5Co0j5O2 cathode materials grown by soft-chemistry via various solution methods, Mater. Sci. Eng. B76, 145-165 (2000). 

Prabahan, S. R. S., Saparil, N. B., Michael, S. S., Massot, M., Julien, C., Soft-chemistry syntethis of electrochemically-active spinel LiMn204 for Li-ion batteries, Solid State Ionics 112, 25-34 (1998). 

Rouxel, J., Tournoux, M. and Brec, R. (eds)(1994) Soft Chemistry Routes to New Materials Chimie Douce, Trans Tech Publications, pp. 422. 

Soft Chemistry , proximity to nature and bionics contain the idea that chemical-technical solutions from nature can provide a stimulus for industrial processes and products. 

Cd -vZnvS (48-50) or dilute magnetic semiconductors like Cdi vMn,.S (51,52). Recently, as described later, CdTe has been prepared via a soft chemistry, for the first time. 

Synthesis by soft chemistry made the first disodium telluride, Na2Te. This product is highly poisonous and oxidable. To make Na2Te we used the two procedures... 

In this edition, we have incorporated new material in all the chapters and updated references to the literature. New sections dealing with porous solids, fullerenes and related materials, metal nitrides, metal tellurides, molecular magnets and other organic materials have been added. Under preparative strategies, we have included new types of synthesis reported in the literature, specially those based on soft chemistry routes. We have a new section covering typical results from empirical theory and electron spectroscopy. There is a major section dealing with high-temperature oxide superconductors. We hope that this edition of the book will prove to be a useful text and reference work for all those interested in solid state chemistry and materials science. 

D.S. Bern, J.D. Houmes and H.-C. zur Loye. In Soft Chemistry Routes To New Materials, (Trans Tech Publications, Universite de Nantes, 1994), 183. 

Materials chemistry contains all the elements of modem chemistry. These include synthesis, structure, dynamics, and properties. In synthesis, one employs all possible methods and conditions from high-temperature and high-pressure techniques to mild solution methods (chimie douce or soft chemistry).3 Chemical methods generally tend to be more delicate, often yielding novel, metastable products. Kinetic rather than thermodynamic control of reactions favors the formation of such structures. Supramolecular organization provides new ways of designing materials. 

In solid state chemistry, a special term soft chemistry was proposed to describe the methods based on preliminary synthesis of intermediate compounds which are further used to prepare final products [4]. One of the authors of this monograph has introduced the term soft mechanochemistry for mechanochemical reactions with the participation of highly reactive compounds [30]. They include the reactions with the participation of compounds containing oxygen-hydrogen groups as well as other relatively unstable compounds such as peroxides, nitrates, metal carbonates and other reactive compounds. 

Iron vanadate, FeV04, is a prospective material for lithium rechargeable batteries and in catalysis. In [90] mechanical coactivation of iron and vanadium oxides was used to prepare intimate nanoscale mixture, similar to those prepared by soft chemistry. Reduction of this mixture at the same temperature and oxygen partial pressure conditions as of soft chemistry products (500°C and 10 Pa) leads to formation of a nanometric vanadium ferrite with the only spinel phase. The characterization of the powders thus prepared was perfomed by X-ray diffraction, SEM, IR spectrometry, thermogravimetry and colourimetry. It was shown that the homogeneity of grain size and chemical composition is achieved if the initial oxides have similar grain size. 

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