The intermetallic materials digold bismuthide, gold diantimonide, and gold ditelluride were chemically synthesized with a bottom-up wet chemical approach, which has not been achieved before. These gold-based materials display a nano- to microparticle grain size and a well-defined composition-based structure. True intermetallic nanoparticle-based materials have traditionally proven challenging to obtain via wet chemical approaches, making the materials created here significant from a fundamental synthesis standpoint. The knowledge gained by developing reliable synthesis approaches toward intermetallic nanoparticles may be used to develop new materials and enhance the understanding of how to refine the characteristics and enhanced properties of emerging nanoparticle semiconductor materials in advanced applications such as for thermoelectrics.

Climate change, diminishing reserves of fossil fuels, energy security, and consumer demand all depend on alternatives to our current course of energy usage and consumption. A broad consensus concurs that implementing energy efficiency and renewable energy technologies are necessities now rather than luxuries to be deferred to some distant future. Neither effort can effect serious change in our energy patterns without marked improvements in electrical energy storage, with electrochemical energy storage in batteries and electrochemical capacitors serving as key components of any plausible scenario.1,2 Consumer expectations of convenience and long-lived portable power further drive the need to push these old devices onto a new performance curve. This issue of MRS Bulletin addresses the significant advances occurring in research laboratories around the world as old electrode materials and designs are re-envisioned, and abandoned materials of the past are reinvigorated by arranging matter and function on the nanoscale to bring batteries and electrochemical capacitors into the 21st century.

The lithium intercalation chemistry of LiNb6Cl15, a 16 e− Nb-cluster, has been explored in order to obtain new Nb-cluster compounds. As a result, three different phases have been detected. Full de-intercalation of lithium produces Nb6Cl15, a new 15 e− Nb-cluster. The oxidation reaction is reversible since lithium can be intercalated again to produce the parent LiNb6Cl15. On the other hand, intercalation of lithium into LiNb6Cl15 seems to proceed through two single phases with the following stoichiometries: Li1.5Nb6Cl15 and Li3Nb6Cl15. For these two compositions the extra electrons (0.5 and 2 respectively/formula) should enter the eg* molecular orbitals arising from Nb-Nb interactions inside the cluster. The reductions of LiNb6Cl15 leading to these two new electron-rich Nb-cluster are reversible as detected by chronopotentiometry.

Poly(methyl methacrylate)/MgAl layer double hydroxides (PMMA/MgAl LDH) nanocomposites were prepared by in situ free radical polymerization with the organic modified MgAl-K2 LDH in the methyl methacrylate monomer and initiator of benzoyl peroxide. The morphology of MgAl-K2 LDH and PMMA/MgAl-K2 LDH nanocomposites were investigated by transmission electron microscopy (TEM) and powder X-ray diffraction, indicated that the MgAl-K2 LDH were dispersed in PMMA matrix to form PMMA/MgAl-K2 LDH nanocomposites with heterogeneous morphology comprising both exfoliated and intercalated PMMA/MgAl-K2 LDH nanocomposites . The thermal and mechanical characterization were carried out by thermogravimetric analysis (TGA) ¡Bdifferential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The properties of PMMA/MgAl-K2 LDH nanocomposites exhibit the better thermal and mechanical properties.

The surfactant cetyltrimethylammonium ion (CTA+) was confined within the galleries of montmorillonite (MMT) to obtain a series of organo-montmorillonites (C16-MMTs) through an ion-exchange intercalation reaction. The C16-MMT formed a single precipitate layer when CTA+ loading was 18.3 wt% but stratified at high loadings. The conformational disorder increased with increasing CTA+ loading. The upper precipitate was characterized by a larger gallery height and a higher surfactant loading in comparison with lower precipitate. The confined methylene chains adopted a lateral monolayer with a small percentage of conformation freedoms at CTA+ loading of 18.3 wt%. The intercalated methylene chains were arranged either in a lateral monolayer or in a tilted interdigitated bilayer at CTA+ loading of 24.7 wt% while in either a tilted interdigitated bilayer or a lateral bilayer at high CTA+ loadings. The different arrangements of methylene chains intercalated in the MMT galleries are believed to be the reason for the stratification.

The microwave irradiation technique (MWIT) was applied to synthesize lithium manganese oxide having spinel structure using LiOH·H2O and ε–MnO2 as starting materials. The crystal and electronic structure depends on the irradiation time; x-ray diffraction patterns of the sample irradiated for 9 min were in good agreement with that of cubic structure without showing the peak of MnO2. The electronic structure of synthesized samples before and after lithium ion intercalation and/or deintercalation was investigated by Mn L-edge and O K-edge x-ray absorption spectroscopy.