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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]

With the continuous research and development of amidoxime (AO)‐based adsorbents, industrialization production of uranium from seawater gradually becomes a reality. However, the currently available AO‐based adsorbents still suffer from low adsorption rate and poor selectivity. Herein, vertically aligned polyamioxime–graphene oxide (VA‐PG) sheet membrane is fabricated by directional freeze casting. The run‐through microchannels contribute to the free diffusion of uranyl ions (UO22+), leading to the fast adsorption kinetics. Furthermore, partially reduced graphene oxide allows high photothermal conversion efficiency and rapid in‐plane heat transfer, resulting in the fast temperature rise under simulated sunlight irradiation. Because of the endothermic behavior of UO22+, light‐irradiated VA‐PG can simultaneously satisfy the requirements of high adsorption capacity (13.63 mg‐U g‐Ads−1), high adsorption rate (0.43 mg g−1 day−1), and excellent selectivity toward U(VI) over V(V) (U/V = 1.24) in natural seawater, indicating the right direction for a breakthrough in the field of uranium extraction from seawater. [ABSTRACT FROM AUTHOR]

Uranium plays an indispensable role in the sustainable development of nuclear industry, and the recovery of uranium from nuclear wastewater is one way to solve the shortage of uranium resources. However, the recovery of uranium resources from nuclear wastewater remains a challenge due to the interfere of coexisting ions. Herein, ratios of the adsorption group and photocatalytic enrichment group are well‐designed and controllably assembled into the porous aromatic frameworks (PAFs) using molecular engineering strategy to realize high uranium recovery efficiency and high resistance to interfering ions. The optimally coordinated multivariate PAF material PAF‐AN2T8‐AO exhibits bifunctions of adsorption and photocatalytic enrichment and thus, achieves high enrichment selectivity and high uranium recovery efficiency of 99% under simulated sunlight irradiation. Compared to PAFs with only adsorption group or photocatalytic group, the uranium recovery capacity of the optimized PAF is enhanced by 1.2 times and 2.3 times, respectively. Mechanistic studies reveal that the product of photocatalytic uranium on PAF‐AN2T8‐AO is air‐stabilized solid crystal metastudtite ((UO2)O2∙2H2O). This work provides a guiding method for designing adsorption‐photocatalytic bifunctional materials and proposes a more environmentally adaptable strategy for dispersed uranium resource recovery. [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]

Highly efficient recovery of uranium from seawater is of great concern because of the growing demand for nuclear energy. The use of amidoxime‐based polymeric fiber adsorbents is considered to be a promising approach because of their relatively high specificity and affinity to uranyl. The surface area, hydrophility, and surface charge of the adsorbent are reported to be critical factors that influence uranium recovery efficiency. Here, a porous amidoxime‐based nanofiber adsorbent (SMON–PAO) that exhibits the highest uranium recovery capacity among the existing fiber adsorbents both in 8 ppm uranium spiked seawater (1089.36 ± 64.31 mg‐U per g‐Ads) and in natural seawater (9.59 ± 0.64 mg‐U per g‐Ads) is prepared by blow spinning. These nanofibers are obtained by compositing polyacrylamidoxime with montmorillonite and exhibit the increased surface area and more exposed functional amidoxime moieties for uranyl adsorption. The residual montmorillonite enhances the hydrophility and reduces the negative surface charge, thereby increasing the contact of the adsorbent with seawater and reducing the charge repulsion between negative amidoxime group and negative uranyl species ([UO2(CO3)3]4−). The finding of this study indicates that rational design of uranium recovery adsorbents by comprehensive utilizing the key factors that influence uranium recovery performance is a promising approach for developing economically feasible uranium recovery materials. A porous amidoxime‐based nanofiber adsorbent (SMON–PAO) is rationally designed to achieve high uranium recovery capacity from seawater and fabricated by blow spinning. This finding indicates that design of uranium recovery adsorbents by comprehensively utilizing the factors that influence uranium recovery performance, which are surface area, hydrophility, and surface charge, is a promising approach for developing economically feasible uranium recovery adsorbents. [ABSTRACT FROM AUTHOR]