The hydrosilylation reaction is one of the largest-scale application of homogeneous catalysis and is widely used to enable the commercial manufacture of silicon products. However, considerable issues including disposable platinum consumption, undesired side reactions and unacceptable catalyst residues still remain. Here, we synthesize a heterogeneous partially charged single-atom platinum supported on anatase TiO (Pt/TiO) catalyst via an electrostatic-induction ion exchange and two-dimensional confinement strategy, which can catalyze hydrosilylation reaction with almost complete conversion and produce exclusive adduct. Density functional theory calculations reveal that unexpected property of Pt/TiO originates from atomic dispersion of active species and unique partially positive charge Pt electronic structure that conventional nanocatalysts do not possess. The fabrication of single-atom Pt/TiO catalyst accomplishes a reasonable use of Pt through recycling and maximum atom-utilized efficiency, indicating the potential to achieve a green hydrosilylation industry.

electricity on a large scale with ultralow greenhouse gases emission. [2] Uranium is the most critical ingredient for the production of nuclear power. In order for nuclear power to be a sustainable energy generation in the future, economically viable sources of uranium beyond terrestrial ores must be developed. [3] The oceans hold ≈4.5 billion tons of uranium, [4] making them a potential huge resource to support nuclear power production for hundreds of years. [5] All that is required is the ability to capture this element from seawater in cost-and energy-efficient ways. In the last decades, researchers worldwide have tried various methods to recover uranium from seawater and aqueous solution, such as coprecipitation, [6] ion-exchange, [7] adsorption via porous organic polymers, [8,9] and organic-inorganic hybrid adsorbents. [10][11][12][13][14][15][16] Among these technologies, the adsorption approach, particularly by using fiber-based adsorbents, is recognized as the most feasible process in terms of practicality, processability, cost, and environmental concerns. [3,17] In the 1990s, Japan Atomic Energy Agency (JAEA) research teams had successfully captured over 1083 g of uranium directly from ocean by using nonwoven fabric adsorbent, firmly establishing the practicality of uranium recovery from the oceans in appreciable quantities. [3,18] Uranium extraction from seawater via fiber adsorption has recentlyThe oceans contain hundreds of times more uranium than terrestrial ores. Fiber-based adsorption is considered to be the most promising method to realize the industrialization of uranium extraction from seawater. In this work, a pre-amidoximation with a blow spinning strategy is developed for mass production of poly(imide dioxime) nanofiber (PIDO NF) adsorbents with many chelating sites, excellent hydrophilicity, 3D porous architecture, and good mechanical properties. The structural evidences from 13 C NMR spectra confirm that the main functional group responsible for the uranyl binding is not "amidoxime" but cyclic "imidedioxime." The uranium adsorption capacity of the PIDO NF adsorbent reaches 951 mg-U per g-Ads in uranium (8 ppm) spiked natural seawater. An average adsorption capacity of 8.7 mg-U per g-Ads is obtained after 56 d of exposure in natural seawater via a flowthrough column system. Moreover, up to 98.5% of the adsorbed uranium can be rapidly eluted out and the adsorbent can be regenerated and reused for over eight cycles of adsorption-desorption. This new blow spun PIDO nanofabric shows great potential as a new generation adsorbent for uranium extraction from seawater.

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The uranium level in seawater is ≈1000 times as high as terrestrial ores and can provide potential near‐infinite fuel for the nuclear energy industry. However, it is still a significant challenge to develop high‐efficiency and low‐cost adsorbents for massively extracting uranium from seawater. Herein, a simple and fast method through low‐energy consumption sunlight polymerization to direct fabrication of a poly(amidoxime) (PAO) hydrogel membrane, which exhibits high uranium adsorption capacity, is reported. This PAO hydrogel owns semi‐interpenetrating structure and a hydrophilic poly(acrylamide) 3D network of hydrogel which can disperse and fix PAOs well. As a result, the amidoxime groups of PAOs exhibit an outstanding uranium adsorption efficiency (718 ± 16.6 and 1279 ± 14.5 mg g −1 of m uranium / m PAO in 8 and 32 ppm uranium‐spiked seawater, respectively) among reported hydrogel‐based adsorbents. Most importantly, U‐uptake capacity of this hydrogel can achieve 4.87 ± 0.38 mg g −1 of m uranium / m dry gel just after four weeks within natural seawater. Furthermore, this hydrogel can be massively produced through low‐energy consumption and environmentally‐friendly sunlight polymerization. This work will provide a high‐efficiency and low‐cost adsorbent for massive uranium extraction from seawater.

Marine sponges are used as biomonitors of heavy metals contamination in coastal environment as they process large amounts of water and have a high capacity for accumulating heavy metals. Here, inspired by the unique physical and physiological features of marine sponges, a surface engineered synthetic sponge for the highly efficient harvesting of uranium from natural seawater is developed. An ultrathin poly(imide dioxime) (PIDO)/alginate (Alg) interpenetrating polymer network hydrogel layer is uniformly wrapped around the skeleton of a melamine sponge (MS) substrate through a simple dippingdrying-crosslinking process, providing the hybrid MS@PIDO/Alg sponge with excellent uranium adsorption performance and sufficient mechanical strength to withstand the harsh conditions of practical applications. The maximum adsorption capacity reaches 910.98 mg-U g-gel -1 for the PIDO/Alg hydrogel layer and 291.51 mg-U g-sponge -1 for the whole hybrid MS@PIDO/ Alg sponge in uranium-spiked natural seawater. The adsorption capacity measured after 56 d of exposure in 5 tons of natural seawater is evaluated to be 5.84 mg-U g-gel -1 (1.87 mg-U g-sponge -1 ). This novel approach shows great promise for the mass production of high-performance sponge adsorbent for uranium recovery from natural seawater and nuclear waste.

Fort he practical extraction of uranium from seawater,a dsorbents with high adsorption capacity,f ast equilibrium rate,h igh selectivity,a nd long service life are needed. Herein, ac himeric spidroin-based super uranyl-binding protein (SSUP) fiber was designed by fusing the gene of super uranyl-binding protein (SUP) with the gene of spidroin. SUP endowed the SSUP fiber with high affinity and selectivity to uranium, and spidroin gave the SSUP fiber with high mechanical strength and high reusability.T he wet SSUP fiber is aw ater-rich hydrogel-like structure,w hich provided abundant hydrophilic intermolecular space for the entrance of uranyl ions,a nd could accelerate the rate for uranium adsorption. In seawater,t he SSUP fiber achieved ab reakthrough uranium extraction capacity of 12.33 mg g À1 with an ultrashort equilibration time of 3.5 days,suggesting that SSUP fiber might be ap romising adsorbent for uranium extraction from the natural seawater.Uranium is ak ey element of the nuclear-energy industry, which accounts for 13 %o ft he worldse lectricity supply without greenhouse gas generation. [1] Theocean, with atotal amount of 4.5 billion tons of uranium, is estimated to contain thousands of times of more uranium than terrestrial uranium reserves. [2] As ac onsequence of low solubility,t he concentration of soluble uranium in seawater is only 3.3 ppb (mgkg À1 ). [3] In addition, the coexisting marine interference metal ions,e specially vanadium, can seriously compete with uranium and make the extraction of uranium from seawater challenging. [4] Meanwhile,t he complex marine environment can severely hazard the adsorbents and reduces the service life of adsorbents.T hus,t he development of uranium adsorbents with high loading capacity,h igh specificity,f ast saturation time,h igh reusability,a nd strong mechanical property,are highly desirable.Amidoxime-based polymer adsorbents exhibit high potential because of their relatively high selectivity and binding capacity and have been used in uranium recovery from seawater since the 1980s. [2a] Fiber adsorbents based on the amidoxime group achieved the highest reported uranium extraction capacities of 1089 mg g À1 in uranium-spiked simulated seawater and 9.59 mg g À1 in real seawater. [5] The polymer fiber adsorbents are thus thought to be the optimal strategy for industrial recovery of uranium from seawater. [3, 6] However,t he saturation time of amidoxime-based polymer adsorbents is usually 4to8weeks in natural seawater, [7] which significantly reduces the efficiency and increases the economic cost for uranium extraction. Based on ah alf-wave rectified alternating current electrochemical (HW-ACE) method, the uranium extraction kinetics and capacity were enhanced to 1932 mg g À1 in 1000 ppm (mg kg À1 )u ranium spiked simulated seawater. [8] Recently,i norganic oxides/ sulfides, [9] metal-organic frameworks, [10] porous organic polymers, [11] covalent organic frameworks, [12] porous aromatic frameworks, [13] and carbon-based adsorbents [14] have been developed...

Highly efficient recovery of uranium from seawater is of great concern because of the growing demand for nuclear energy. The use of amidoximebased 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 ([UO 2 (CO 3 ) 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.

The ocean reserves 4.5 billion tons of uranium and amounts to a nearly inexhaustible uranium supply. Biofouling in the ocean is one of the most severe factors that hazard uranium extraction and even cause the failure of uranium extraction. Therefore, development of uranium adsorbents with biofouling resistance is highly urgent. Herein, a strategy for constructing anti‐biofouling adsorbents with enhanced uranium recovery capacity in natural seawater is developed. This strategy can be widely applied to modify currently available carboxyl‐contained adsorbents, including the most popular amidoxime‐based adsorbent and carboxyl metal organic framework adsorbent, using a simple one‐step covalent cross‐link reaction between the antibacterial compound and the adsorbent. The prepared anti‐biofouling adsorbents display broad antibacterial spectrum and show more than 80% inhibition to the growth of marine bacteria. Benefitting from the tight covalent cross‐link, the anti‐biofouling adsorbents show high reusability. The modified amidoxime‐based adsorbents show enhanced uranium recovery capacity both in sterilized and bacteria‐contained simulated seawater. The anti‐biofouling adsorbent Anti‐UiO‐66 constructed in this study exhibits 24.4% increased uranium recovery capacity, with a uranium recovery capacity of 4.62 mg‐U per g‐Ads, after a 30‐day field test in real seawater, suggesting the strategy is a promising approach for constructing adsorbents with enhanced uranium extraction performance.