Researchers in China have developed a dipolar passivation method that reduces defects and improves charge transport in solar cells based on narrow-bandgap tin lead perovskite, enabling the fabrication of all-perovskite tandem solar cells with efficiencies of around 30% and enhanced stability. The dipolar passivation strategy strengthens the ohmic contact, promotes efficient hole injection into the hole transport layer, and repels electrons from the perovskite interface, reducing non-radiative recombination and carrier transport losses. The cell achieved a power conversion efficiency of 24.9% and retained around 87% of its initial efficiency after 1,025 hours, showing promising long-term stability. The researchers aim to further improve the dipolar passivation method for enhanced stability in tandem devices, contributing to the ongoing efforts to develop more efficient and sustainable solar energy solutions.