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As the power‐conversion efficiency (PCE) of organic–inorganic lead halide perovskite solar cells (PSCs) is approaching the theoretical maximum, the most crucial issue concerns long‐term ambient stability. Here, the application of PCN‐224 quantum dots (QDs) is reported, a typical Zr‐based porphyrinic metal–organic framework (MOF), to enhance the ambient stability of PSCs. PCN‐224 QDs with abundant Lewis‐base groups (e.g., CO, C−N, CN) contribute to high‐quality perovskite films with enlarged grain size and reduced defect density by interaction with under‐coordinated Pb2+. Meanwhile, PCN‐224 QDs enable the well‐matched energy level at the perovskite/hole transport layer (HTL) interface, thereby facilitating hole extraction and transport. More importantly, PCN‐224 QDs‐treated HTL can capture Li+ from bis(trifluoromethanesulfonyl)imide additive, leading to the reduced aggregation and less direct contact with moisture for hygroscopic Li‐TFSI. Moreover, PCN‐224 QDs mitigated Li+ ion migration into the perovskite layer, thus avoiding the formation of deleterious defects. The resultant devices yield a champion PCE of 22.51%, along with substantially improved durability, including humidity, thermal and light soaking stabilities. The findings provide a new approach toward efficient and stable PSCs by applying MOF QDs. [ABSTRACT FROM AUTHOR]

Efficient removal of uranium from uranium‐containing nuclear wastewater is of great significance for utilizing uranium resources and protecting the environment from uranium hazards. In this paper, a polyamidoxime‐coated coconut haustorium derived magnetic biochar (CHMBC‐PAO) composite adsorbent with excellent adsorption performance, magnetism, recyclability, and photothermal conversion properties in complex environments is prepared through a simple soak‐gelation coating method for efficient removal of uranium from nuclear wastewater. The coconut haustorium biochar, carbonized by a sponge‐like organ inside the sprouted coconut, can provide rich functional groups and electronegative surface, which are conducive to the loading of functional materials and the adsorption of uranyl, respectively. The CHMBC‐PAO presents 2.4 emu g−1 saturation magnetization, making it can be efficiently recovered through magnetic recovery. It can convert absorbed light into thermal energy through molecular thermal vibration and non‐radiative relaxation process of excitons. Enhanced by the photothermal effect, CHMBC‐PAO shows an extra high uranium adsorption capacity of 310.30 mg g−1 in acidic nuclear wastewater within a short period of time, surpassing the adsorption capacity of most reported uranium removal materials. Meanwhile, the CHMBC‐PAO also presented excellent ion selectivity and reusability. Therefore, CHMBC‐PAO composite adsorbent can be considered as a potential candidate for treating radioactive nuclear wastewater. [ABSTRACT FROM AUTHOR]