A designed nanostructure with MoS2 nanosheets (NSs) perpendicularly grown on graphene sheets (MoS2/G) is achieved by a facile and scalable hydrothermal method, which involves adsorption of Mo7O24(6-) on a graphene oxide (GO) surface, due to the electrostatic attraction, followed by in situ growth of MoS2. These results give an explicit proof that the presence of oxygen-containing groups and pH of the solution are crucial factors enabling formation of a lamellar structure with MoS2 NSs uniformly decorated on graphene sheets. The direct coupling of edge Mo of MoS2 with the oxygen from functional groups on GO (C-O-Mo bond) is proposed. The interfacial interaction of the C-O-Mo bonds can enhance electron transport rate and structural stability of the MoS2/G electrode, which is beneficial for the improvement of rate performance and long cycle life. The graphene sheets improve the electrical conductivity of the composite and, at the same time, act not only as a substrate to disperse active MoS2 NSs homogeneously but also as a buffer to accommodate the volume changes during cycling. As an anode material for lithium-ion batteries, the manufactured MoS2/G electrode manifests a stable cycling performance (1077 mAh g(-1) at 100 mA g(-1) after 150 cycles), excellent rate capability, and a long cycle life (907 mAh g(-1) at 1000 mA g(-1) after 400 cycles).

A metallic nanoparticle-decorated ceramic anode was prepared by in situ reduction of the perovskite Sr2FeMo0.65Ni0.35O6-δ (SFMNi) in H2 at 850 °C. The reduction converts the pure perovksite phase into mixed phases containing the Ruddlesden-Popper structure Sr3FeMoO7-δ, perovskite Sr(FeMo)O3-δ, and the FeNi3 bimetallic alloy nanoparticle catalyst. The electrochemical performance of the SFMNi ceramic anode is greatly enhanced by the in situ exsolved Fe-Ni alloy nanoparticle catalysts that are homogeneously distributed on the ceramic backbone surface. The maximum power densities of the La0.8Sr0.2Ga0.8Mg0.2O3-δ electrolyte supported a single cell with SFMNi as the anode reached 590, 793, and 960 mW cm(-2) in wet H2 at 750, 800, and 850 °C, respectively. The Sr2FeMo0.65Ni0.35O6-δ anode also shows excellent structural stability and good coking resistance in wet CH4. The prepared SFMNi material is a promising high-performance anode for solid oxide fuel cells.

Molybdenum disulfide (MoS2), which possesses a layered structure and exhibits a high theoretical capacity, is currently under intensive research as an anode candidate for next generation of Li‐ion batteries. However, unmodified MoS2 suffers from a poor cycling stability and an inferior rate capability upon charge/discharge processes. Herein, a unique nanocomposite comprising MoS2 nanothorns epitaxially grown on the backbone of carbon nanotubes (CNTs) and coated by a layer of amorphous carbon is synthesized via a simple method. The epitaxial growth of MoS2 on CNTs results in a strong chemical coupling between active nanothorns and carbon substrate via CS bond, providing a high stability as well as a high‐efficiency electron‐conduction/ion‐transportation system on cycling. The outer carbon layer can well‐accommodate the structural strain in the electrode upon lithium‐ion insertion/extraction. When employed as an anode for lithium storage, the prepared material exhibits remarkable electrochemical properties with a high specific capacity of 982 mA h g−1 at 0.1 A g−1, as well as excellent long‐cycling stability (905 mA h g−1 at 1 A g−1 after 500 cycles) and superior rate capability, confirming its potential application in high‐performance Li‐ion batteries.

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High-performance Li-ion batteries require materials with well-designed and controlled structures on nanometre and micrometre scales. Electrochemical properties can be enhanced by reducing crystallite size and by manipulating structure and morphology. Here we show a method for preparing hierarchically structured Li4Ti5O12 yielding nano- and microstructure well-suited for use in lithium-ion batteries. Scalable glycothermal synthesis yields well-crystallized primary 4–8 nm nanoparticles, assembled into porous secondary particles. X-ray photoelectron spectroscopy reveals presence of Ti+4 only; combined with chemical analysis showing lithium deficiency, this suggests oxygen non-stoichiometry. Electron microscopy confirms hierarchical morphology of the obtained material. Extended cycling tests in half cells demonstrates capacity of 170 mAh g−1 and no sign of capacity fading after 1,000 cycles at 50C rate (charging completed in 72 s). The particular combination of nanostructure, microstructure and non-stoichiometry for the prepared lithium titanate is believed to underlie the observed electrochemical performance of material.