Above 10% efficiency earth-abundant Cu2ZnSn(S,Se)4 solar cells by introducing alkali metal fluoride nanolayers as electron-selective contacts

The present investigation mainly addresses the open circuit voltage issue in kesterites based Cu2ZnSn(S,Se)4 solar cells by introducing an alkali metal fluoride electron-selective nanolayer between ITO and CdS without a conventional hole-blocking ZnO layer.300