Kesterite

South Korean scientists have built a kesterite solar cell based on a zinc tin oxide (ZTO) buffer layer. It offers almost the same efficiency as kesterite cells based on toxic cadmium sulfide buffer layers, as the energy of the electrons between the kesterite absorber layer and ZTO buffer layer are aligned.

Researchers in South Korea have analyzed the effects of alkali doping on the fill factor of kesterite solar cells and have built a device on a flexible metal foil optimized with a sodium fluoride doping layer.

Scientists in India have developed a new molecular precursor for applications in kesterite solar cells. They used the precursor to build a superstrate type solar cell with an efficiency that is purportedly among the highest ever recorded. They relied on a low-temperature process to manufacture the device.

An international research group has found that the presence of a few lattice defects in a kesterite PV cell material can actually improve efficiency, rather than lowering it. The group believes that kesterite PV cells could see mass production within the next decade.

German scientists have developed a new process for the formation of a phase pure kesterite Cu2ZnSnSe4 (CZTSe), which they claim can improve the material homogeneity and suppress the well-known issue of tin losses. The new technique is based on stacked elemental and alloyed precursors with a Zn/Cu-Sn/Zn precursor structure.

Scientists at South Korea’s Daegu Gyeongbuk Institute of Science and Technology have set a new efficiency record of 11.4% for a cell based on a copper zinc tin sulfide thin film applied to a flexible substrate.