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In this study, the adsorptive behavior of hydrogen atoms adsorbed onto the (110) surface of plutonium dioxide with Ga impurities was analyzed utilizing DFT. The calculations employed the PAW method and were treated within the GGA+U method to correct for the Coulomb interaction. The results indicate that H atoms exhibit distinct adsorption properties on the PuO2(110) surface with Ga impurities compared to those on a pristine PuO2(110) surface.

Rigid molecular sieving materials work well for small molecules with the complete exclusion of large ones 1 – 3 , and molecules with matching physiochemical properties may be separated using dynamic molecular sieving materials 4 – 6 . Metal–organic frameworks (MOFs) 7 – 9 are known for their precise control of structures and functions on a molecular level 10 – 15 . However, the rational design of local flexibility in the MOF framework for dynamic molecular sieving remains difficult and challenging. Here we report a MOF material (JNU-3a) featuring one-dimension channels with embedded molecular pockets opening to propylene (C 3 H 6 ) and propane (C 3 H 8 ) at substantially different pressures. The dynamic nature of the pockets is revealed by single-crystal-to-single-crystal transformation upon exposure of JNU-3a to an atmosphere of C 3 H 6 or C 3 H 8 . Breakthrough experiments demonstrate that JNU-3a can realize high-purity C 3 H 6 (≥99.5%) in a single adsorption–desorption cycle from an equimolar C 3 H 6 /C 3 H 8 mixture over a broad range of flow rates, with a maximum C 3 H 6 productivity of 53.5 litres per kilogram. The underlying separation mechanism—orthogonal-array dynamic molecular sieving—enables both large separation capacity and fast adsorption–desorption kinetics. This work presents a next-generation sieving material design that has potential for applications in adsorptive separation. A dynamic molecular sieve made from a metal–organic framework with orthogonally arrayed pockets is capable of separating propylene (C 3 H 6 ) from a propylene (C 3 H 6 )/propane (C 3 H 8 ) gas mixture.

Radioactive molecular iodine (I 2 ) and organic iodides, mainly methyl iodide (CH 3 I), coexist in the off-gas stream of nuclear power plants at low concentrations, whereas few adsorbents can effectively adsorb low-concentration I 2 and CH 3 I simultaneously. Here we demonstrate that the I 2 adsorption can occur on various adsorptive sites and be promoted through intermolecular interactions. The CH 3 I adsorption capacity is positively correlated with the content of strong binding sites but is unrelated to the textural properties of the adsorbent. These insights allow us to design a covalent organic framework to simultaneously capture I 2 and CH 3 I at low concentrations. The developed material, COF-TAPT, combines high crystallinity, a large surface area, and abundant nucleophilic groups and exhibits a record-high static CH 3 I adsorption capacity (1.53 g·g −1 at 25 °C). In the dynamic mixed-gas adsorption with 150 ppm of I 2 and 50 ppm of CH 3 I, COF-TAPT presents an excellent total iodine capture capacity (1.51 g·g −1 ), surpassing various benchmark adsorbents. This work deepens the understanding of I 2 /CH 3 I adsorption mechanisms, providing guidance for the development of novel adsorbents for related applications. Radioactive molecular iodine (I 2 ) and methyl iodide (CH 3 I) coexist in the off-gas stream of nuclear power plants at low concentrations and only few adsorbents can effectively adsorb low-concentration I 2 and CH 3 I simultaneously. Here, the authors demonstrate simultaneous capture of I 2 and CH 3 I at low concentrations by exploiting different adsorptive sites in a covalent organic framework.

The operation of traditional aqueous-electrolyte zinc-ion batteries is adversely affected by the uncontrollable growth of zinc dendrites and the occurrence of side reactions. These problems can be avoided by the development of functional hydrogel electrolytes as replacements for aqueous electrolytes. However, the mechanism by which most hydrogel electrolytes inhibit the growth of zinc dendrites on a zinc anode has not been investigated in detail, and there is a lack of a large-scale recovery method for mainstream hydrogel electrolytes. In this paper, we describe the development of a recyclable and biodegradable hydrogel electrolyte based on natural biomaterials, namely chitosan and polyaspartic acid. The distinctive adsorptivity and inducibility of chitosan and polyaspartic acid in the hydrogel electrolyte triggers a double coupling network and an associated synergistic inhibition mechanism, thereby effectively inhibiting the side reactions on the zinc anode. In addition, this hydrogel electrolyte played a crucial role in an aqueous acid-based Zinc/MnO 2 battery, by maintaining its interior two-electron redox reaction and inhibiting the formation of zinc dendrites. Furthermore, the sustainable biomass-based hydrogel electrolyte is biodegradable, and could be recovered from the Zinc/MnO 2 battery for subsequent recycling. Functional hydrogel electrolytes show promising potential for enhancing the sustainability of aqueous zinc-ion batteries. Here, the authors introduce a biomass-based hydrogel electrolyte that not only prevents side reactions on the zinc anode but also enables easy retrieval from the zinc batteries.

Direct photocatalytic CO 2 reduction from primary sources, such as flue gas and air, into fuels, is highly desired, but the thermodynamically favored O 2 reduction almost completely impedes this process. Herein, we report on the efficacy of a composite photocatalyst prepared by hyper-crosslinking porphyrin-based polymers on hollow TiO 2 surface and subsequent coordinating with Pd(II). Such composite exhibits high resistance against O 2 inhibition, leading to 12% conversion yield of CO 2 from air after 2-h UV-visible light irradiation. In contrast, the CO 2 reduction over Pd/TiO 2 without the polymer is severely inhibited by the presence of O 2 ( ≥ 0.2 %). This study presents a feasible strategy, building Pd(II) sites into CO 2 -adsorptive polymers on hollow TiO 2 surface, for realizing CO 2 reduction with H 2 O in an aerobic environment by the high CO 2 /O 2 adsorption selectivity of polymers and efficient charge separation for CO 2 reduction and H 2 O oxidation on Pd(II) sites and hollow TiO 2 , respectively. While selective CO 2 reduction is crucial for its removal from the environment, the presence of O 2 hinders this process. Here authors show CO 2 photoreduction in the presence of O 2 by incorporating Pd(II) sites into a coordination polymer on TiO 2 to selectively adsorb CO 2 .

Atmospheric ozone has long been a threat to human health, however, rational design of high-performance O 3 -decomposition catalysts remains challenging. Herein, we demonstrate the great potential of a series of isomorphous bimetallic MOFs denoted as PCN-250(Fe 2 M) (M = Co 2+ , Ni 2+ , Mn 2+ ) in catalytic O 3 decomposition. Particularly, PCN-250(Fe 2 Co) showed 100% O 3 removal efficiency for a continuous air flow containing 1 ppm O 3 over a wide humidity range (0 ‒ 80% RH) at room temperature. Mechanism studies suggested that the high catalytic performance originated from the introduction of open Co(II) sites as well as its porous structure. Additionally, at low pressures around 10 Pa, PCN-250(Fe 2 Co) exhibited high adsorption capacities (89 ‒ 241 mg g −1 ) for most VOCs, which are not only a class of hazardous air pollutants but also the precursor of O 3 . This work opens up a new avenue to develop advanced air purification materials for O 3 and VOCs removal in one. Warm-season O 3 pollution has been increasingly frequent worldwide in the past few years, exposing a threat to human health as well as the natural environment. Here, the authors showcase a stable MOF which can not only effectively capture various airborne VOCs, but decompose trace O 3 in ambient air.

The magnesium-aluminum layered double hydroxides (MgAl-LDHs) with different molar ratios were prepared by hydrothermal method for the effective removal of fluoride ions (F−) from adsorbed water. The results showed that it was rich with CO32− anions in the interlayer of prepared MgAl-LDHs, which made it significantly better than activated Al2O3 in removing adsorbed F−. The adsorption performance of F− on MgAl-LDHs was evaluated, and the results indicated that the MgAl-LDHs demonstrated a remarkable following the pseudo-second-order kinetics for successfully removing F− through a monolayer adsorption process following the Langmuir isotherms models. The equilibrium adsorption capacity reached 43.1 mg·g−1 for MgAl-LDHs-3 with the metal molar ratio of 6:4. MgAl-LDHs can easily be used several times after calcination for the adsorptive removal of F−. After five cycles of regeneration experiments, the removal efficiency of the MgAl-LDHs-3 adsorbent for fluoride ions still reached 78%.

Global investment in counteracting climate change has galvanized increasing interest in carbon capture and sequestration (CCS) as a versatile emissions mitigation technology. As decarbonization efforts accelerate, CCS can target the emissions of large point-source emitters, such as coal- or natural gas-fired power plants, while also supporting the production of renewable or low-carbon fuels. Furthermore, CCS can enable decarbonization of difficult-to-abate industrial processes and can support net CO 2 removal from the atmosphere through bioenergy coupled with CCS or direct air capture. Here we review the development of porous materials as next-generation sorbents for CO 2 capture applications. We focus on stream- and sector-specific challenges while highlighting case studies within the context of the rapidly shifting energy landscape. We conclude with a discussion of key needs from the materials community to expand deployment of carbon capture technologies. Porous materials can selectively and reversibly adsorb large quantities of gas. This Review highlights progress made in using this class of materials for CO 2 capture processes and discusses key gaps that the materials community can address to accelerate greater adoption of adsorptive carbon capture technologies.

The integrated CO 2 capture and conversion (iCCC) technology has been booming as a promising cost-effective approach for Carbon Neutrality. However, the lack of the long-sought molecular consensus about the synergistic effect between the adsorption and in-situ catalytic reaction hinders its development. Herein, we illustrate the synergistic promotions between CO 2 capture and in-situ conversion through constructing the consecutive high-temperature Calcium-looping and dry reforming of methane processes. With systematic experimental measurements and density functional theory calculations, we reveal that the pathways of the reduction of carbonate and the dehydrogenation of CH 4 can be interactively facilitated by the participation of the intermediates produced in each process on the supported Ni–CaO composite catalyst. Specifically, the adsorptive/catalytic interface, which is controlled by balancing the loading density and size of Ni nanoparticles on porous CaO, plays an essential role in the ultra-high CO 2 and CH 4 conversions of 96.5% and 96.0% at 650 °C, respectively. The integrated CO 2 capture and conversion (iCCC) technology has been booming for carbon neutrality. Here the authors optimized the Ni–CaO composite catalyst to promote iCCC involving consecutive high-temperature Calcium-looping and dry reforming of methane and illustrated their synergistic promotions at the suitable catalyst interface.

Magnetic Fe 3 O 4 nanoparticles (NPs) were successfully synthesized via co-precipitation method using ferric chloride and ferrous sulphate as the starting materials. The shape and the size of Fe 3 O 4 NPs were controlled by using different types of additive including ammonium hydroxide and sodium hydroxide. The results revealed that by adding ammonium hydroxide, the particles attained a spherical shape with a uniform size. On the other hand, the shape of the particles turned from spherical to cubic using sodium hydroxide. The magnetic results showed that both samples attained hysteresis loop, which indicated that both samples have ferromagnetic behavior. In addition, Fe 3 O 4 NPs with cubic shape showed higher adsorptive behaviour towards Congo red compared to spherical Fe 3 O 4 NPs, which is attributed to the enhancement of their magnetic properties. The adsorption of Congo red onto cubic Fe 3 O 4 NPs was best described by Langmuir isotherm model, while spherical Fe 3 O 4 NPs followed Freundlich isotherm model.