Researchers at the National University of Singapore (NUS), Chinese Academy of Sciences (CAS) and Avantama have developed a new interface using antimony doped tin oxides (ATOx), that creates a chemically stable interface between the cell layers that's more uniform, conducts electricity better, and is more transparent. This enabled reduced energy loss and improved cell efficiency - 25.7% (certified steady-state efficiency of 24.8%) for an area of 0.05 cm2, retained under maximum power point tracking over 500 h and 24.6% (certified steady-state efficiency of 24.0%) for an area of 1 cm2.
The team reported p-type antimony-doped tin oxides (ATOx) combined with a self-assembled monolayer molecule as an interlayer between the perovskite and hole-transporting layers (HTL) in inverted solar cells. The scientists said that ATOx increases the chemical stability of the interface; they showed that the redox reaction that commonly took place at the NiOx/perovskite interface is negligible at the ATOx/perovskite interface.
The scientists demonstrated that ATOx suppresses non-radiative recombination in the perovskite layer and enhances the depletion at the perovskite/HTL interface for efficient charge extraction.