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Structural changes at electrode/electrolyte interface of a lithium cell were studied by X-ray reflectometry and two-dimensional model electrodes with a restricted lattice plane of LiMn 2 O 4 . The electrodes were constructed with an epitaxial film synthesized by the pulsed laser deposition method. The orientation of the film depends on the substrate plane; the ͑111͒, ͑110͒, and ͑100͒ planes of LiMn 2 O 4 grew on the ͑111͒, ͑110͒, and ͑100͒ planes of the SrTiO 3 substrates, respectively. The ex situ reflectometry indicated that a thin impurity layer covered the lattice plane of the as-grown film. The impurity layer was dissolved and a solid-electrolyteinterface-like phase appeared after the electrode was soaked into the electrolyte. A defect layer was formed in the ͑111͒ plane, whereas no density changes were detected for the other lattice planes. The in situ observation clarified that the surface reactivity depended on the lattice planes of the spinel; the defect layer at the ͑111͒ plane was stable during the electrochemical reaction, whereas a slight decrease in the film thickness was observed for the ͑110͒ plane. Our surface characterization of the intercalation electrode indicated that the surface structure changes during the pristine stage of the change-discharge processes and these changes are dependent on the lattice orientation of LiMn 2 O 4 .Because the lithium-ion configuration composed of carbon anodes and intercalation cathodes has been widely accepted for lithium secondary batteries, significant efforts have been devoted to attain high energy and power densities to produce an excellent energy storage system. 1 In particular, recent progress in pure electric vehicles ͑EVs͒ and hybrid electric vehicles ͑HEVs͒ require high power density operation for the current battery systems. The power characteristics of the battery system are closely related to the nature of electrode reactions, which is composed of several reaction steps proceeded in series: lithium diffusion in the electrolyte, adsorption of solvated lithium on the cathode surface, desolvation, surface diffusion, charge-transfer reaction, intercalation from the surface to the bulk, and the bulk diffusion of lithium in the electrode material. Recent electrochemical studies have claimed that the desolvation process was the rate-determining step of the whole electrode reaction. 2,3 It is well known that electrode surfaces are almost covered with a passive surface layer, which is generally called the solid electrolyte interface ͑SEI͒. The idea of the SEI layer was originally introduced on the alkali and alkaline earth metal in organic electrolytes, 4 and then it is believed that the layer plays a key role in the electrochemical performance, particularly the calendar life of lithium batteries. Many experimental techniques such as X-ray photoelectron spectroscopy ͑XPS͒, 5-8 IR spectroscopy, 9,10 nuclear magnetic resonance ͑NMR͒, 11 and ellipsometry 12 have been employed to study the nature and formation mechanism of the SEI layer.Among the materials prop...

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Conventional chiral ligands rely on the use of a covalently constructed, single chiral molecule embedded with coordinative functional groups. Here, we report a new strategy for the design of a chiral ligand for asymmetric transition-metal catalysis; our approach is based on the development of an achiral cationic ammonium-phosphine hybrid ligand paired with a chiral binaphtholate anion. This ion-paired chiral ligand imparts a remarkable stereocontrolling ability to its palladium complex, which catalyses a highly enantioselective allylic alkylation of α-nitrocarboxylates. By exploiting the possible combinations of the achiral onium entities with suitable coordinative functionalities and readily available chiral acids, this approach should contribute to the development of a broad range of metal-catalysed, stereoselective chemical transformations.