Patent ID: 8252265

Claim:
A method for making a chalcopyrite-type compound, comprising: reacting a reaction mixture in a first solvent under reflux condition to form the chalcopyrite-type compound containing M 1 , M 2 , and A, in which M 1 is selected from Cu, Au, Ag, Na, Li, and K, M 2 is selected from In, Ga, Al, Ti, Zn, Cd, Sn, Mg, and combinations thereof, and A is selected from S, Se, Te, and combinations thereof; filtering the reaction mixture after the reaction so as to obtain a crude cake of the chalcopyrite-type compound; mixing the crude cake with a second solvent and a powder of a post-treatment material selected from S, Se, Te, and combinations thereof so as to form a treatment mixture; and heating the treatment mixture under reflux condition in a manner to permit the crude cake to undergo a post treatment for removing impurities from the crude cake.