Electrical & Computer Engineering, Department of


Date of this Version



33rd IEEE Photovoltaic Specialists Conference, 2008. PVSC '08. Digital Object Identifier: 10.1109/PVSC.2008.4922729 Publication Year: 2008 , Page(s): 1 - 6
Copyright 2008 IEEE. Used by permission.


Reaction pathway investigations of the solvothermal preparation of nanocrystalline Culn1- xGaxSe2 in triethylenetetramine reveal the early formation of a previously unreported Cu2-xSe(S) intermediate. Over 24 hours, this reacts with In and Se species to form CulnSe2(s). If Ga is present, the reaction proceeds over an additional 48 hours to form Culn1-xGaxSe2. Adding ammonium halide salts reduces the CulnSe2 formation time to as little as 30 minutes. It is proposed that in these cases, Cu2-xSe particle growth is limited via a competitive Cu-halide complex formation. The smaller Cu2-xSe particles may react and form CulnSe2 more rapidly. A reaction pathway scheme consistent with experimental results and previous literature reports is proposed.