Ultra-thin crystalline films of ZnS and PbS formed at the organic–aqueous interface

Ultra-thin films of ZnS have been prepared by the reaction of zinc cupferronate or zinc stearate in a toluene solution with an aqueous solution of Na2S. The films have been examined by electron microscopy and other techniques. The reaction at the interface yields excellent films which are generally single-crystalline. The effects of reaction parameters such as temperature and reactant concentration have been examined. Ultra-thin crystalline films of PbS have been obtained by the reaction of a toluene solution of lead cupferronate with the aqueous solution of Na2S. The organic–aqueous interface provides a simple and elegant method of producing good crystalline films of important semiconducting materials.