Monolithic perovskite/black-silicon tandems based on tunnel oxide passivated contacts

Perovskite/silicon tandems offer a promising pathway to increase the efficiency beyond the Auger limit of silicon at minimal additional cost. However, it is challenging to accommodate the solution-processed perovskite without flattening or reducing pyramidal texture of silicon subcells. Herein, we report the first monolithic perovskite/silicon tandem featuring an industrially applicable front-side-nanostructured black silicon with a tunnel oxide passivated contact (TOPCon). The TOPCon together with the surface reconstruction of black silicon contributes to the high-level surface passivation without sacrificing the broadband light trapping. Additionally, the reconstructed nanotexture significantly facilitates the wetting of perovskite and acts as a nanoconfining scaffold to guide the vertical growth of perovskite. The resulting tandem yields a certified efficiency of 28.2%, representing one of the highest efficiencies reported on either perovskite/TOPCon or double-side-textured perovskite/silicon tandems.