Synthesis of Quaternary Chalcogenide Nanocrystals: Stannite Cu2ZnxSnySe1+x+2y

摘要

great deal of attention as low-cost alternatives to conventionalnphotovoltaic materials. Among them, Cu2ZnSnS4 has been recentlynprepared by three different wet organometallic routes.1–3 In spitenof this excellent progress, shape and size control of quaternarynnanocrystals is still a challenge to overcome. An alternativenquaternary chalcogenide with high potential for photovoltaics isnCu2ZnSnSe4 (CZTSe). CZTSe combines many advantageous characteristicsnfor optoelectronic applications, such as a suitable bandngap (1.0-1.5 eV),4 a high optical absorption coefficient (up to 105ncm-1),5 low toxicity, and a relative abundance of its elements. Innaddition, CZTSe films have promising thermoelectric properties,nwith ZT values of ∼0.4 at 700 K.6 While CZTSe films have beennprepared by coevaporation,5 sputtering,7 and pulsed laser deposition,n8 to the best of our knowledge, no report devoted to thenpreparation of CZTSe nanocrystals by wet chemical methods hasnbeen published to date. Here we present a colloidal synthetic routenfor the production of nonstoichiometric CZTSe (Cu2ZnxSnySe1+x+2y)nnanoparticles with a narrow size distribution.