We develop a simple and economical thermal annealing method for the synthesis of phosphorus-doped graphene, which exhibits remarkable electrocatalytic activity towards the oxygen reduction reaction and enhances the electrochemical performance as an anode material for lithium ion batteries. The experimental results suggest the significant role of phosphorus atoms in graphene.

Iron carbide nanoparticles have long been considered to have great potential in new energy conversion, nanomagnets, and nanomedicines. However, the conventional relatively harsh synthetic conditions of iron carbide hindered its wide applications. In this article, we present a facile wet-chemical route for the synthesis of Hägg iron carbide (Fe(5)C(2)) nanoparticles, in which bromide was found to be the key inducing agent for the conversion of Fe(CO)(5) to Fe(5)C(2) in the synthetic process. Furthermore, the as-synthesized Fe(5)C(2) nanoparticles were applied in the Fischer-Tropsch synthesis (FTS) and exhibited intrinsic catalytic activity in FTS, demonstrating that Fe(5)C(2) is an active phase for FTS. Compared with a conventional reduced-hematite catalyst, the Fe(5)C(2) nanoparticles showed enhanced catalytic performance in terms of CO conversion and product selectivity.

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In nur sechs Stufen gelang die Totalsynthese von Eupomatilon‐3 in 48 % Gesamtausbeute dank der Entwicklung einer dynamischen kinetischen Racematspaltung, mit der ein racemisches α,β‐ungesättigtes Butenolid in hoher Ausbeute und mit hohem Enantiomeren‐ und Diastereomerenüberschuss reduktiv umgewandelt werden kann. Diese kupferkatalysierte Racematspaltung wurde bei mehreren α,β‐ungesättigten γ‐Arylbutenoliden angewendet.

Lithium ion batteries (LIBs) possess energy densities higher than those of the conventional batteries, but their lower power densities and poor cycling lives are critical challenges for their applications to electric vehicles (EVs) or grid stations. The energy and power densities, as well as the life of LIBs are dependent on electrodes where sluggish diffusion control process and structural stability are the main concerns. Here, the lithium storage mechanism of anode materials and the Goodenough diagram to explain the potential of cell and key parameters to determine the performance of an anode are highlighted. The cost reduction parameters and the availability of anode materials for future batteries on the basis of their resources and performances will be discussed. Further, the recent progress on anode nanostructures and solutions to the associated challenges will be outlined. The use of several techniques to determine the dynamic variations in nanostructures including both structural and chemical changes of electrode nanostructures during cycling as well as the limitations for high load applications will be explained. Finally, the concluding remarks will highlight the characteristics for both anode and cathode for better choice of electrode combinations in the full batteries.

Due to their unique properties, together with their ease of synthesis and functionalization, graphene-based materials have been showing great potential in energy storage and conversion. These hybrid structures display excellent material characteristics, including high carrier mobility, faster recombination rate and long-time stability. In this review, after a short introduction to graphene and its derivatives, we summarize the recent advances in the synthesis and applications of graphene and its derivatives in the fields of energy storage (lithium ion, lithium-air, lithium-sulphur batteries and supercapacitors) and conversion (oxygen reduction reaction for fuel cells). This article further highlights the working principles and problems hindering the practical applications of graphene-based materials in lithium batteries, supercapacitors and fuel cells. Future research trends towards new methodologies to the design and the synthesis of graphene-based nanocomposite with unique architectures for electrochemical energy storage and conversion are also proposed. The Royal Society of Chemistry.

Phase-controlled nickel sulfide (Ni3 S4 and NiS1.03 ) nanoparticle (NP)/nitrogen-doped graphene (NG) composites are prepared through a facile one-pot hydrothermal process. The composites show ultrahigh capacity retentions of 98.87% and 95.94% for Ni3 S4 /NG and NiS1.03 /NG electrodes, respectively, as anode materials for lithium ion batteries.

It is extremely desirable but challenging to create highly active, stable, and low-cost catalysts towards oxygen reduction reaction to replace Pt-based catalysts in order to perform the commercialization of fuel cells. Here, a novel iron nitride/nitrogen doped-graphene aerogel hybrid, synthesized by a facile two-step hydrothermal process, in which iron phthalocyanine is uniformly dispersed and anchored on graphene surface with the assist of π-π stacking and oxygen-containing functional groups, is reported. As a result, there exist strong interactions between Fe x N nanoparticles and graphene substrates, leading to a synergistic effect towards oxygen reduction reaction. It is worth noting that the onset potential and current density of the hybrid are significantly better and the charge transfer resistance is much lower than that of pure nitrogen-doped graphene aerogel, free Fe x N and their physical mixtures. The hybrid also exhibits comparable catalytic activity as commercial Pt/C at the same catalyst loading, while its stability and resistance to methanol crossover are superior. Interestingly, it is found that, apart from the active nature of the hybrid, the large surface area and porosity are responsible for its excellent onset potential and the high density of Fe-N-C sties and small size of Fe x N particles boost charge transfer rate.