Tin and germanium monochalcogenide IV-VI semiconductor nanocrystals for use in solar cells.

The incorporation of colloidal semiconductor nanocrystals into the photoabsorbant material of photovoltaic devices may reduce the production costs of solar cells since nanocrystals can be readily synthesized on a large scale and are solution processable. While the lead chalcogenide IV-VI nanocrystals have been widely studied in a variety of photovoltaic devices, concerns over the toxicity of lead have motivated the exploration of less toxic materials. This has led to the exploration of tin and germanium monochalcogenide IV-VI semiconductors, both of which are made up of earth abundant elements and possess properties similar to the lead chalcogenides. This feature article highlights recent efforts made towards achieving synthetic control over nanocrystal size and morphology of the non-lead containing IV-VI monochalcogenides (i.e., SnS, SnSe, SnTe, GeS and GeSe) and their application toward photovoltaic devices.