NEW DIRECTIONS IN TIN SULFIDE MATERIALS CHEMISTRY

Tin sulfide-based materials can exist in many forms, ranging from disc rete molecular species, to 1D chains, 2D dense and porous sheets and 3 D open frameworks. The local coordination geometry around a tin center may vary from trigonal pyramidal, to tetrahedral, trigonal bipyramida l and octahedral, and around sulfur from terminal, v-shaped to trigona l pyramidal. The oxidation state may take + 2 and + 4 for tin and -2, -1, 0 for sulfur. The tin sulfide chemistry is further enriched by the catenation ability of sulfur. In addition, other elements (metal and non-metal) can be incorporated into the tin sulfide structures to yiel d ternary and quaternary materials. More importantly, using the recent developed 'soft chemistry' synthetic approach, various novel porous t in (poly)sulfide materials have emerged that display interesting optic al, electrical and adsorption properties. Representative tin sulfide m aterials will be presented and discussed in this review to demonstrate the development of tin sulfide chemistry in the last three decades.