Identifying the origin of the <i>V</i>_oc deficit of kesterite solar cells from the two grain growth mechanisms induced by Sn²⁺ and Sn⁴⁺ precursors in DMSO solution

Abstract

The large V_oc deficit of kesterite solar cell mainly comes from the defective surface caused by multi-phase fusion grain growth; direct phase transformation grain growth produces high quality absorber with clean surface and thus high device V_oc.