Figure 6From: Nanoscale investigation of surface potential distribution of Cu2ZnSn(S,Se)4 thin films grown with additional NaF layers The schematics of band diagram around GB in (a) without NaF and (b) with NaF layer in CZTSSe thin-films. The surface potential energy increases 160 meV around grain boundary with NaF layer. In case (b) Electron–hole carriers more efficiently help separate at the GB.Back to article page