Understanding the growth mechanism of wurtzite Cu2ZnSnS4 nanocrystals and the photodegradation properties

Abstract High quality wurtzite Cu 2 ZnSnS 4 (W-CZTS) nanocrystals (NCs) could be easily obtained by a simple green one-pot reaction process. Forming mechanism of the nanocrystals was investigated by XRD and Raman characterization. It demonstrated that forming W-CZTS started with nucleation of Cu 2 S, then Sn 4 + diffused into Cu 2 S to form the Cu 2 SnS 3 , finally Zn 2 + diffused into Cu 2 SnS 3 to obtain W-CZTS. The optical and photocatalytic results of the W-CZTS NCs indicated that W-CZTS nanocrystals with copper-poor composition showed a better photocatalytic activity (the degradation of MB (methylene blue) could reach up to 81.79%). Moreover, this non-injected one-pot method could be further popularized and become a common approach to synthesize other quaternary wurtzite Cu 2 MSnS 4 (M = Fe 2 + , Co 2 + , Ni 2 + , Mn 2 + , Mg 2 + ) nanocrystals.