Metal‐halide perovskite has emerged as an effective photovoltaic material for its high power conversion efficiency (PCE), low cost and straightforward fabrication techniques. Unfortunately, its long‐term operational durability, mainly affected by halide ion migration and undercoordinated Pb2+ is still the bottleneck for its large‐scale commercialization. In this work, an ionic liquid (IL) is designed to effectively cap the grain surface for improved stability and reduced trap density. More specifically, the Br− in the IL passivates the undercoordinated Pb2+ by chemically bonding to it, resulting in a thin layer of ionic‐liquid‐perovskite formed on the surface, leading to improved photovoltaic performance and better stability. Specifically, the solar cell exhibits an open‐circuit voltage of 1.192 V and PCE of 24.33% under one‐sun illumination with negligible hysteresis, and a large area (10.75 cm2) integrated module achieves PCE of 20.33%. Moreover, the bare device maintains over 90% of its initial efficiency after 700 h of aging at 65 °C. It also shows outstanding stability with only about 10% degradation after being exposed to the ambient environment for 1000 h. The superior efficiency and stability demonstrate that the present IL passivating strategy is a promising approach for high‐performance large area perovskite solar cell applications.

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The self-healing phenomenon universally existed in organisms (from molecular level repair of DNA to macroscopic level repair of the soft tissue) is extremely important for organisms to maintain their normal physiological functions. As a smart soft material, self-healing gels attracted much attention owing to repair the damaged structures and functions just like biological features. There is a great challenge to design novel self-healing gels in order to meet the need of multi-functional flexible gels. Endowing self-healing gels with photoluminescent property can promote and extend the applications of gels in biomedical field (biological imaging, drug delivery and biosensors, etc.) and engineering (optical switch, pH sensors and thermal sensors, etc.), which attracts more attention of researchers. This paper reviews the latest design ideas, performance of photoluminescent self-healing gels and their potential applications. The challenges and future development about photoluminescent self-healing gels is also proposed here.