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A one‐dimensional (1D) halogen‐bridged dinuclear‐metal complex (MMX‐chain) exhibits various electronic states based on a mixed‐valence metal‐dimer system. This report deals with the synthesis and physical properties of a new MMX‐chain with a bulky pendant ligand, Pt2(mcc‐HexCS2)4I (mcc‐HexCS2=trans‐4‐(methoxycarbonyl)cyclohexanedithiocarboxylate). The steric hindrance caused by the bulky substituent induces a strain in its 1D chain, achieving at ambient condition the first pure alternate charge‐polarization (ACP) state (−Pt2+−Pt3+−I−−Pt3+−Pt2+−I−−), a kind of spin‐Peierls state, as confirmed by X‐ray diffraction and its conducting and magnetic properties. The strain effect is also manifested as a very large linear thermal expansion along the chain direction, which is quite different from conventional MMX‐chains without a bulky ligand. The design of low‐dimensional materials with ligand variations is expected to lead to the emergence of new electron–lattice coupled electronic states. [ABSTRACT FROM AUTHOR]

Heterostructured catalysts show outstanding performance in electrochemical reactions owing to their beneficial interfacial properties. However, the rational design of heterostructured catalysts with the desired interfacial properties and charge‐transfer characteristics is challenging. Herein, we developed a SrMn3O6−x‐SrMnO3 (SMOx‐SMO) heterostructure through epitaxial growth, which demonstrated excellent electrocatalyst performance for the oxygen reduction reaction (ORR). The formation of high‐valence Mn3+/4+ is beneficial for promoting a positive shift in the position of the d‐band center, thereby optimizing the adsorption and desorption of ORR intermediates on the heterojunction surface and resulting in improved catalytic activity. When SMOx‐SMO was applied as an air‐electrode catalyst in a rechargeable zinc‐air battery, a high output voltage and power density was achieved, with performance comparable to a battery prepared with Pt/C‐IrO2 air‐electrode catalysts, albeit with much better cycling stability. [ABSTRACT FROM AUTHOR]

Herein we report an efficient synthesis to prepare O‐doped nanographenes derived from the π‐extension of pyrene. The derivatives are highly fluorescent and feature low oxidation potentials. Using electrooxidation, crystals of cationic mixed‐valence (MV) complexes were grown in which the organic salts organize into face‐to‐face π‐stacks, a favorable solid‐state arrangement for organic electronics. Variable‐temperature electron paramagnetic resonance (EPR) measurements and relaxation studies suggest a strong electron delocalization along the longitudinal axis of the columnar π‐stacking architectures. Electric measurements of single crystals of the MV salts show a semiconducting behavior with a remarkably high conductivity at room temperature. These findings support the notion that π‐extension of heteroatom‐doped polycyclic aromatic hydrocarbons is an attractive approach to fabricate nanographenes with a broad spectrum of semiconducting properties and high charge mobilities. [ABSTRACT FROM AUTHOR]