Recently, the research group led by Renxing Lin and Hairen Tan from the College of Engineering and Applied Science at Nanjing University has made breakthroughs in the field of manufacturing technology for all-perovskite tandem solar cells. The team developed a developed a dipolar passivation strategy, simultaneously reduces the defect density at the buried interface of mixed Pb-Sn perovskite and enables precise energy level adjustment at the HTL/perovskite interface. This dipolar-induced passivation strengthens the ohmic contact at the interface, facilitating efficient hole injection into the HTL while driving electrons away from the HTL/Pb-Sn perovskite interface. This approach increases the carrier diffusion length to 8.3 μm characterized by terahertz probe and allows us to improve the PCE of Pb-Sn perovskite solar cells to 24.9%, along with a high open-circuit voltage (Voc) of 0.911 V, a Jsc of 33.1 mA cm^-2 and a high FF of 82.6%. Meanwhile, the dipolar passivation effectively mitigates the contact losses in the NBG subcell introduced by the interconnecting layer of tandem device, demonstrating a record-high PCE of 30.6% (certified stabilized 30.1%) in all-perovskite tandem solar cells. This marks the first time that the efficiency of polycrystalline thin-film solar cells has exceeded 30%. The relevant research results were published on October 27, 2025, in the journal Nature under the title "All-perovskite tandem solar cells with dipolar passivation."

Source:  https://www.nature.com/articles/s41586-025-09773-7