Tin-based amorphous and composite materials

In recent years increasing attention has been devoted to tin composite oxide glasses (TCO glasses), which are most promising candidates as anode materials in lithium secondary batteries and they are also desirable from environmental viewpoint low melting glasses, sensing elements, non-linear optical materials and coatings. The aim of this paper is to review the studies of SnO-based oxide glasses and to present our experience in developing such amorphous materials. The obstacles in producing such materials are oxidation or disproportionation of SnO at high temperatures. Different techniques were applied to established reproducible methods for the synthesis of Sn-containing glasses. Tin oxide glasses were obtained in the binary systems with classical glass-former oxides: SnO–SiO₂, SnO–GeO₂, SnO–B₂O₃, SnO–P₂O₅, SnO–BPO₄ and in oxyhalide systems SnX₂–P₂O₅, (X = F, Cl). SnO essentially improves some technological characteristics of glasses, but many unsolved problems regarding the mechanism of its influence still remain. Depending on the composition, SnO tends to change its behavior from network-modifier to network-former. But the structural role and chemistry of tin in inorganic glasses is still not clearly understood. Our studies were focused on the systems of SnO–P₂O₅, SnO–P₂O₅–MO (M = Zn, Ba), SnCl₂–P₂O₅, SnCl₂–P₂O₅–MeCl₂ (Me_nO_m). The influence on the quality of glasses of different factors, such as nature of raw materials, the batch preparation and the melting conditions, has been studied. Low-melting stable glasses have been obtained at ambient atmosphere.