Graphene Interface Engineering for Perovskite Solar Modules: 12.6% Power Conversion Efficiency over 50 cm² Active Area

Interfaces between perovskite solar cell (PSC) layer components play a pivotal role in obtaining high-performance premium cells and large-area modules. Graphene and related two-dimensional materials (GRMs) can be used to “on-demand” tune the interface properties of PSCs. We successfully used GRMs to realize large-area (active area 50.6 cm 2 ) perovskite-based solar modules (PSMs), achieving a record high power conversion efficiency of 12.6%. We on-demand modulated the photoelectrode charge dynamic by doping the mesoporous TiO 2 (mTiO 2 ) layer with graphene flakes. Moreover, we exploited lithium-neutralized graphene oxide flakes as interlayer at the mTiO 2 /perovskite interface to improve charge injection. Notably, prolonged aging tests have shown the long-term stability for both small- and large-area devices using graphene-doped mTiO 2 . Furthermore, the possibility of producing and processing GRMs in the form of inks opens a promising route for further scale-up and stabilization of the PSM, the gateway for the commercialization of this technology.