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Abstract Electrochemical technologies add a unique dimension for ore refinement, representing tunable methods that can integrate with renewable energy sources and existing downstream process flows. However, the development of electrochemical extraction technologies has been impeded by the technological maturity of hydro- and pyro-metallurgy, as well as the electrical insulating properties of many metal oxide ores. The fabrication and use of carbon/insulating material composite electrodes has been a longstanding method to enable electrochemical activation. Here, using real hectorite ore, we employ this technical approach to fabricate hectorite-carbon black composite electrodes (HCCEs) and achieve electrochemical activation of hectorite. Anodic polarization results in lithium-ion release through a multi-step chemical and electrochemical mechanism that results in 50.7 ± 4.4% removal of lithium from HCCE, alongside other alkaline ions. This technical proof-of-concept study underscores that electrochemical activation of ores can facilitate lattice deterioration and ion removal from ores.

Abstract Metal-organic frameworks (MOFs) are highly attractive porous materials with applications spanning the fields of chemistry, physics, biology, and engineering. Their exceptional porosity and structural flexibility have led to widespread use in catalysis, separation, biomedicine, and electrochemistry. Currently, most MOFs are synthesized under equilibrium liquid-phase reaction conditions. Here we show a general and versatile non-equilibrium flame aerosol synthesis of MOFs, in which rapid kinetics of MOF formation yields two distinct classes of MOFs, nano-crystalline MOFs and amorphous MOFs. A key advantage of this far-from-equilibrium synthesis is integration of different metal cations within a single MOF phase, even when this is thermodynamically unfavorable. This can, for example, produce single-atom catalysts and bimetallic MOFs of arbitrary metal pairs. Moreover, we demonstrate that dopant metals (e.g., Pt, Pd) can be exsolved from the MOF framework by reduction, forming nanoclusters anchored on the MOF. A prototypical example of such a material exhibited outstanding performance as a CO oxidation catalyst. This general synthesis route opens new opportunities in MOF design and applications across diverse fields and is inherently scalable for continuous production at industrial scales.

Abstract The Hume-Rothery rules governing solid-state miscibility limit the compositional space for new inorganic material discovery. Here, we report a non-equilibrium, one-step, and scalable flame synthesis method to overcome thermodynamic limits and incorporate immiscible elements into single phase ceramic nanoshells. Starting from prototype examples including (NiMg)O, (NiAl)Ox, and (NiZr)Ox, we then extend this method to a broad range of Ni-containing ceramic solid solutions, and finally to general binary combinations of elements. Furthermore, we report an “encapsulated exsolution” phenomenon observed upon reducing the metastable porous (Ni0.07Al0.93)Ox to create ultra-stable Ni nanoparticles embedded within the walls of porous Al2O3 nanoshells. This nanoconfined structure demonstrated high sintering resistance during 640 h of catalysis of CO2 reforming of methane, maintaining constant 96% CH4 and CO2 conversion at 800 °C and dramatically outperforming conventional catalysts. Our findings could greatly expand opportunities to develop novel inorganic energy, structural, and functional materials.

Weak interactions between substrates and the active site environment have been known to be vital in enzyme catalysis. Inspired by this, the authors synthesize hyper-crosslinked porous polymer-based catalysts with different H-bonds to enhance adsorption and modify the interfacial sites and reactivity.

Layered double hydroxides (LDH) are ideal for charge storage, however, the sluggish reaction dynamics are obstacle to their development. Here, triggered by mismatching integration of Mn sites, the authors configure wrinkled Mn/NiCo-LDH with strains and defects, where promoted mass & charge transport behaviors are realized.

Layered boron compounds attract enormous interest in applications. This work reports first-principles calculations coupled with global optimization to show that the outer boron surface in MgB2 nanosheets undergo disordering and clustering, which is experimentally confirmed in synthesized MgB2 nanosheets.

Heavy metals and metalloids pose major threats to health and environmental ecosystems, thus systems for low-cost remediation are needed. Here the authors report the scalable design of a hydrogen-bonded organic–inorganic framework for selective removal of trace heavy metal ions from water.

The design of solution-processed thermoelectric nanomaterials with efficient, stable performance remains a challenge. Here, the authors report an in-situ doping method based on nanoscale interface engineering to realize n-type thermoelectric nanowires with high performance and stability.

To realize the potential of soft hybrid (inorganic-organic) materials for thermoelectrics, the underlying transport-related physics must be understood. Here, the authors extend the Kang-Synder framework with experimental analysis to gain insight on the thermoelectric transport in hybrid materials.

Despite recent success in developing new covalent organic frameworks (COFs) materials, synthesis of chemically stable COFs still remains challenging. Here the authors demonstrate a facile strategy that transforms imine-linked COFs into robust porous aromatic frameworks by kinetically fixing the reversible imine linkage via an aza-Diels-Alder cycloaddition reaction.

Abstract Thermoelectric power generation can play a key role in a sustainable energy future by converting waste heat from power plants and other industrial processes into usable electrical power. Current thermoelectric devices, however, require energy intensive manufacturing processes such as alloying and spark plasma sintering. Here, we describe the fabrication of a p-type thermoelectric material, copper selenide (Cu2Se), utilizing solution-processing and thermal annealing to produce a thin film that achieves a figure of merit, ZT, which is as high as its traditionally processed counterpart, a value of 0.14 at room temperature. This is the first report of a fully solution-processed nanomaterial achieving performance equivalent to its bulk form and represents a general strategy to reduce the energy required to manufacture advanced energy conversion and harvesting materials.

Low thermal conductivities in nanomeshes have been attributed to both wave-like and particle-like behaviour of phonons. Here, the authors use periodicity-controlled silicon nanomeshes to show that the particle backscattering effect dominates for periodicities above 100 nm and temperatures above 14 K.

Hydrogen fuel cell electric vehicles are poised to transform the automotive industry, but the lack of safe, high density solid state hydrogen storage solutions is stifling progress. Here, the authors develop a graphene oxide/magnesium nanocomposite which appears to overcome many of the existing challenges.

Nature Communications 7:10804 Article number 10804 (2016); Published 23 February 2016; Updated 18 March 2016 The financial support for this Article was not fully acknowledged. The Acknowledgements should have included the following: The authors gratefully acknowledge research support from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Fuel Cell Technologies Office, under Contract No.