UNSW researchers build 12.6%-efficient kesterite solar cell with lower open-circuit voltage losses

UNSW researchers developed a defect-engineering strategy for wide-bandgap CZTS solar cells that suppresses copper out-diffusion and harmful defects, achieving a 12.6% efficiency and 852.8 mV open-circuit voltage. The certified device reached 12.36% efficiency, highlighting the potential of improved defect control for kesterite and tandem photovoltaics.