The increasing demand for portable electronic devices has created significant activity in the development of compact lightweight batteries of high-energy density, and lithium batteries have become attractive in this regard. The commercial lithium cells use lithium cobalt oxide cathodes and the high cost and toxicity of cobalt has prompted the design and synthesis of alternate insertion hosts. Several low-temperature synthesis routes have been pursued during the past few years both to improve the properties of known oxide hosts as well as to access new insertion oxides, particularly metastable phases. This review, after providing a brief background to lithium batteries, lithium insertion compounds, and lithium ion batteries, presents the low-temperature synthesis and electrochemical properties of manganese, cobalt, nickel, iron, vanadium, chromium, titanium, molybdenum, and tin oxides. The use of soft chemistry methods such as sol−gel processing, ion-exchange reactions, hydrothermal reactions, and oxidation−reduction reactions in solutions to obtain oxide hosts are presented.

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Effects of NH3 nitridation on the chemical and electrical properties of N2O oxides have been studied. Compared with NH3-nitrided SiO2, NH3 nitridation does not degrade the electrical properties of N2O oxides, thus resulting in superior impurity diffusion barrier properties, while preserving excellent interface immunity to hot-carrier injection and much lower charge trapping. Correlation studies between the chemical and electrical properties of NH3-nitrided N2O and NH3-nitrided SiO2 have been done to explain these results.

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Reduction of aqueous K(2)MoO(4) with aqueous KBH(4) at ambient temperatures has been investigated systematically to obtain lower valent molybdenum oxides. Several lower valent oxides such as MoO(2), Mo(4)O(11), K(0.26)MoO(3) (red bronze), K(0.30)MoO(3) (blue bronze), and K(0.85)Mo(6)O(17) are formed during the reduction process; however, only MoO(2) has been obtained as single-phase product. The nature of the product formed is strongly influenced by the reducing power of KBH(4). The reducing power increases with decreasing pH or increasing concentration and volume of KBH(4). The as-prepared samples are amorphous as revealed by X-ray diffraction and transmission electron microscopy. They crystallize sharply at around 350-500 degrees C as revealed by differential scanning calorimetry. Since the products formed are amorphous in nature, they may become particularly attractive for battery electrodes and catalysis.