Partitioning of americium from lanthanides (Ln) present in used nuclear fuel plays a key role in the sustainable development of nuclear energy1–3. This task is extremely challenging because thermodynamically stable Am(III) and Ln(III) ions have nearly identical ionic radii and coordination chemistry. Oxidization of Am(III) to Am(VI) produces AmO22+ ions distinct with Ln(III) ions, which has the potential to facilitate separations in principle. However, the rapid reduction of Am(VI) back to Am(III) by radiolysis products and organic reagents required for the traditional separation protocols including solvent and solid extractions hampers practical redox-based separations. Herein, we report a nanoscale polyoxometalate (POM) cluster with a vacancy site compatible with the selective coordination of hexavalent actinides (238U, 237Np, 242Pu and 243Am) over trivalent lanthanides in nitric acid media. To our knowledge, this cluster is the most stable Am(VI) species in aqueous media observed so far. Ultrafiltration-based separation of nanoscale Am(VI)-POM clusters from hydrated lanthanide ions by commercially available, fine-pored membranes enables the development of a once-through americium/lanthanide separation strategy that is highly efficient and rapid, does not involve any organic components and requires minimal energy input.

Hexagonal boron nitride (h-BN) is regarded as one of the most efficient catalysts for oxidative dehydrogenation of propane (ODHP) with high olefin selectivity and productivity. However, the loss of the boron component under a high concentration of water vapor and high temperature seriously hinders its further development. How to make h-BN a stable ODHP catalyst is one of the biggest scientific challenges at present. Herein, we construct h-BN⊃xIn2O3 composite catalysts through the atomic layer deposition (ALD) process. After high-temperature treatment in ODHP reaction conditions, the In2O3 nanoparticles (NPs) are dispersed on the edge of h-BN and observed to be encapsulated by ultrathin boron oxide (BO x ) overlayer. A novel strong metal oxide–support interaction (SMOSI) effect between In2O3 NPs and h-BN is observed for the first time. The material characterization reveals that the SMOSI not only improves the interlayer force between h-BN layers with a pinning model but also reduces the affinity of the B–N bond toward O• for inhibiting oxidative cutting of h-BN into fragments at a high temperature and water-rich environment. With the pinning effect of the SMOSI, the catalytic stability of h-BN⊃70In2O3 has been extended nearly five times than that of pristine h-BN, and the intrinsic olefin selectivity/productivity of h-BN is well maintained.

Reticular chemistry provides opportunities to design solid-state electrolytes (SSEs) with modular tunability. However, SSEs based on modularly designed crystalline metal− organic frameworks (MOFs) often require liquid electrolytes for interfacial contact. Monolithic glassy MOFs can have liquid processability and uniform lithium conduction, which is promising for the reticular design of SSE without liquid electrolytes. Here, we develop a generalizable strategy for the modular design of noncrystalline SSEs based on a bottom-up synthesis of glassy MOFs. We demonstrate such a strategy by linking polyethylene glycol (PEG) struts and nanosized titanium-oxo clusters into network structures termed titanium alkoxide networks (TANs). The modular design allows the incorporation of PEG linkers with different molecular weights, which give optimal chain flexibility for high ionic conductivity, and the reticular coordinative network provides a controlled degree of cross-linking that gives adequate mechanical strength. This research shows the power of reticular design in noncrystalline molecular framework materials for SSEs.

Understanding the atomistic mechanisms of non-equilibrium processes during solid-state synthesis, such as nucleation and grain structure formation of a layered oxide phase, is a critical challenge for developing promising cathode materials such as Ni-rich layered oxide for Li-ion batteries. In this study, we found that the aluminum oxide coating layer transforms into lithium aluminate as an intermediate, which has favorable low interfacial energies with the layered oxide to promote the nucleation of the latter. The fast and uniform nucleation and formation of the layered oxide phase at relatively low temperatures were evidenced using solid-state nuclear magnetic resonance and in situ synchrotron X-ray diffraction. The resulting Ni-rich layered oxide cathode has fine primary particles, as visualized by three-dimensional tomography constructed using a focused-ion beam and scanning electron microscopy. The densely packed fine primary particles enable the excellent mechanical strength of the secondary particles, as demonstrated by in situ compression tests. This strategy provides a new approach for developing next-generation, high-strength battery materials.

Silica is commonly considered an inert support, and limited research has been concentrated on its role in constructing active metal− (hydr)oxide interfaces. Herein, we found that modifying the surface of nickel with silica will significantly promote its catalytic performance toward the water−gas shift reaction (WGSR), and the well-fabricated Ni np @PS(H450) exhibits a WGSR rate of up to 725 ± 7 μmol CO g cat −1 s −1 at 350 °C, which is at the highest level compared with previously reported Ni-based catalysts. Combining the experiment and theory, we demonstrated that Ni δ+ −O−SiO x interfaces divide the Ni surface into small domains consisting of contiguous Ni atoms. With the aid of an ensemble effect, the adsorption energies of CO, OH, and H can be tuned into appropriate ranges. Moreover, the Ni δ+ −O− SiO x interfaces also inhibit the formation of a dense NiO (or Ni(OH) 2 ) layer, thus endowing the catalyst with high stability. This study offers valuable insights into the catalytic mechanism linking Ni and silica, which can aid in the development of high-performance Ni-based catalysts.