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The development of hydrogen fuel cells is greatly hindered by the unwanted generation of H2O2 at the cathode. A non‐Pt cathode catalyst is now shown to be capable of simultaneously reducing both O2 and H2O2, thus rendering H2O2 a useful part of the feed stream. The applicability of this unique catalyst is demonstrated by employing it in a fuel cell running on H2/CO and O2/H2O2. Peroxide allowed: The development of hydrogen fuel cells is greatly hindered by the unwanted generation of H2O2 at the cathode. A non‐Pt cathode catalyst is now shown to be capable of simultaneously reducing both O2 and H2O2, thus rendering H2O2 a useful part of the feed stream. The applicability of this unique catalyst is demonstrated by employing it in a fuel cell running on H2/CO and O2/H2O2. [ABSTRACT FROM AUTHOR]

Abstract: The sodium oxygen battery is a promising metal–air battery; however, the discharge process is not well understood and the major discharge product is still under debate. The discharge products determined the theoretical specific energy and electrochemical performance of the battery. Now it is demonstrated that NaO2 spontaneously disproportionates to Na2O2, no matter whether it is dissolved in solution or stays on the surface. The behaviors of NaO2 in solution and on the surface are different. Solvents play a crucial effect on the disproportionation of dissolved NaO2 species, which is fast in low donor number (DN) solvents such as acetonitrile but sluggish in high DN solvents such as DMSO. In situ XRD results exhibited the different product growing processes in various solvents. Surface NaO2 would slowly disproportionate to Na2O2 anyway, but this process is relatively slow compared to the time span of discharge process and it does not affect the major product on discharge. [ABSTRACT FROM AUTHOR]

The encumbered tetraisocyanide dianion Na2[Fe(CNAr [ABSTRACT FROM AUTHOR]

Graphene production by wet chemistry is an ongoing scientific challenge. Controlled oxidation of graphite introduces oxo functional groups; this material can be processed and converted back to graphene by reductive defunctionalization. Although thermal processing yields conductive carbon, a ruptured and undefined carbon lattice is produced as a consequence of CO2 formation. This thermal process is not understood, but it is believed that graphene is not accessible. Here, we thermally process oxo-functionalized graphene (oxo-G) with a low (4-6 %) and high degree of functionalization (50-60 %) and find on the basis of Raman spectroscopy and transmission electron microscopy performed at atomic resolution (HRTEM) that thermal processing leads predominantly to an intact carbon framework with a density of lattice defects as low as 0.8 %. We attribute this finding to reorganization effects of oxo groups. This finding holds out the prospect of thermal graphene formation from oxo-G derivatives. [ABSTRACT FROM AUTHOR]

Pincer-type complexes [OsH2(CO){PyCH2NHCH2CH2NHP tBu2}] and [OsH2(CO){HN(CH2CH2P iPr2)2}] catalyze the disproportionation reaction of aldehydes via an outer-sphere bifunctional mechanism achieving turnover frequencies up to 14 000 h−1. The N−H group of the catalysts is a key player in this process, elucidated with the help of DFT calculations. [ABSTRACT FROM AUTHOR]

A perovskite-structure oxide containing unusually high-valence Fe3.5+ was obtained by high-pressure synthesis. Instability of the Fe3.5+ in Ca0.5Bi0.5FeO3 is relieved first by charge disproportionation at 250 K and then by intermetallic charge transfer between A-site Bi and B-site Fe at 200 K. These previously unobserved successive charge transitions are due to competing intermetallic and disproportionation charge instabilities. Both transitions change magnetic and structural properties significantly, indicating strong coupling of charge, spin, and lattice in the present system. [ABSTRACT FROM AUTHOR]

The synthesis of the first linear coordinated CuII complex Cu{N(SiMe3)Dipp}2 ( 1 Dipp=C6H5-2,6Pr i2) and its CuI counterpart [Cu{N(SiMe3)Dipp}2]− ( 2) is described. The formation of 1 proceeds through a dispersion force-driven disproportionation, and is the reaction product of a CuI halide and LiN(SiMe3)Dipp in a non-donor solvent. The synthesis of 2 is accomplished by preventing the disproportionation into 1 by using the complexing agent 15-crown-5. EPR spectroscopy of 1 provides the first detailed study of a two-coordinate transition-metal complex indicating strong covalency in the Cu−N bonds. [ABSTRACT FROM AUTHOR]

The disproportionation of elemental sulfur at moderate temperatures is investigated in the redox condensation involving o-halonitrobenzenes 1 and benzylamines 2. As a redox moderator, elemental sulfur plays the dual role of both electron donor and acceptor, generating its lowest and highest oxidation states: S−2 (sulfide equivalent) in benzothiazole 3 and S+6 (sulfate equivalent) in sulfamate 4, and filling the electron gap of the global redox condensation process. Along with this process, a cascade of reactions of reduction of the nitro group of 1, oxidation of the aminomethyl group of 2, metal-free aromatic halogen substitution, and condensation finally led to 2-arylbenzothiazoles 3. [ABSTRACT FROM AUTHOR]

A robust catalyst for the selective dehydrogenation of formic acid to liberate hydrogen gas has been designed computationally, and also successfully demonstrated experimentally. This is the first such catalyst not based on transition metals, and it exhibits very encouraging performance. It represents an important step towards the use of renewable formic acid as a hydrogen-storage and transport vector in fuel and energy applications. [ABSTRACT FROM AUTHOR]

Attractive models: Synthetic ZnII complexes were investigated as models of copper–zinc superoxide dismutase. Superoxide underwent a unique disproportionation reaction in the electrostatic sphere of the complexes (see picture; bpy=2,2′‐bipyridyl). The effectiveness of the ZnII complexes in inducing the disproportionation of superoxide depended on both the Lewis acidity and the coordination geometry of the Zn center. [ABSTRACT FROM AUTHOR]