Abstract: A method for determining a cation which is stable to oxygen radical. Specifically, a lithium air cell which includes at least an air electrode, a negative electrode and a non-aqueous electrolyte that is interposed between the air electrode and the negative electrode. The lithium air cell is characterized in that the nonaqueous electrolyte contains an ionic liquid that does not contain atoms having a positive charge larger than that of a hydrogen atom and is composed of cations, which have an average of the charges carried by atoms other that hydrogen atoms of 0 or less, and counter anions of the cations.

Abstract: This invention provides a catalyst material comprising a conductive material coated with a polynuclear complex molecule derived from at least two types of heteromonocyclic compounds and a catalyst metal coordinated to the coating layer of the polynuclear complex molecule, and a catalyst material comprising a conductive material coated with a polynuclear complex molecule derived from a heteromonocyclic compound and a catalyst metal, which is a composite of a noble metal and a transition metal, coordinated to the coating layer of the polynuclear complex molecule. Such catalyst material of the invention has excellent catalytic performance and serviceability as, for example, an electrode of fuel cells.

Abstract: The present invention primarily intends to provide an air secondary battery that can inhibit deterioration in charge-discharge properties caused by oxygen generated in an air cathode layer during charge. To attain the object, the invention provides an air secondary battery comprising: a power generating element constituted of an air cathode layer containing a conductive material, an anode layer containing an anode active material, and an electrolyte layer formed between the air cathode layer and the anode layer; and an exterior body that houses the power generating element, wherein the exterior body is hermetically sealed with an oxygen-containing gas encapsulated therein; and at a charge start time, a pressure inside of the exterior body is lower than an atmospheric pressure.

Abstract: The present invention provides an electron transfer mediator modified enzyme electrode which can obtain a high current density and exhibit a stable electrode performance by covalently bonding an electron transfer mediator with a surface of a conductive base material constituting the electrode via a specific spacer, and a biofuel cell comprising the electron transfer mediator modified enzyme electrode. An electron transfer mediator modified enzyme electrode comprising a conductive base material connected to an external circuit, an oxidoreductase electron-transferable with the conductive base material and an electron transfer mediator which can mediate electron transfer between the conductive base material and the oxidoreductase, wherein the electron transfer mediator is covalently bonded to the surface of the conductive base material via a spacer containing at least a straight-chain structure, and a biofuel cell comprising the electron transfer mediator modified enzyme electrode.

Abstract: The invention provides: (1) a modified hydrogenase obtained by removing electron-transfer sites from a hydrogenase constituted of: active subunits including active sites having a hydrogen oxidization-reduction activity; and electron-transfer subunits having the electron-transfer sites through which electrons are transferred between the active sites and the outside of the hydrogenase; (2) a modified hydrogenase obtained from a hydrogenase, wherein when the hydrogenase is isolated from bacteria that produces the hydrogenase, a process for exposing the hydrogenase to an oxygen atmosphere is executed; (3) an enzymatic electrode made of at least one of the foregoing modified hydrogenases; and (4) a hydrogenase modification method including: a step of isolating from hydrogenase-producing bacteria; and a step of removing the electron-transfer sites of the electron-transfer subunits from the hydrogenase by exposing the hydrogenase to an oxygen atmosphere.

Abstract: This invention provides a macrocyclic-organic-compound-based catalyst for reducing oxygen having high oxygen-reducing activity. This oxygen-reducing catalyst comprises a conductive support and, supported thereon, a porphyrin complex represented by formula (I): wherein Rs each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom, an amino group, a hydroxyl group, a nitro group, a phenyl group, or a cyano group or adjacent Rs together form a methylene chain having 2 to 6 carbon atoms or aromatic ring; R's each independently represent a thienyl group; and M represents a metal atom selected from the group consisting of Cu, Zn, Fe, Co, Ni, Ru, Pb, Rh, Pd, Pt, Mn, Sn, Au, Mg, Cd, Al, In, Ge, Cr, and Ti, provided that M may bind to a halogen atom, an oxygen atom, —OH, a nitrogen atom, NO, or ?CO.

Abstract: This invention provides a catalyst material comprising a conductive material coated with a polynuclear complex molecule derived from at least two types of heteromonocyclic compounds and a catalyst metal coordinated to the coating layer of the polynuclear complex molecule, and a catalyst material comprising a conductive material coated with a polynuclear complex molecule derived from a heteromonocyclic compound and a catalyst metal, which is a composite of a noble metal and a transition metal, coordinated to the coating layer of the polynuclear complex molecule. Such catalyst material of the invention has excellent catalytic performance and serviceability as, for example, an electrode of fuel cells.