Abstract: A compound of the present disclosure consists of A, Ag, and X. A is a monovalent cation and contains an organic cation. X is at least one selected from the group consisting of a halide ion and a thiocyanate ion. A photoelectric conversion device of the present disclosure includes a first electrode, a photoelectric conversion layer, and a second electrode arranged in this order. The photoelectric conversion device of the present disclosure contains the aforementioned compound of the present disclosure.

Abstract: A solar cell according to the present disclosure comprises a support, a photoelectric conversion element, and a sealing member. The photoelectric conversion element is in a sealed space defined by the support and the sealing member. The photoelectric conversion element comprises, in this order, a first electrode, a photoelectric conversion layer, and a second electrode, and an oxygen concentration in the sealed space is greater than or equal to 10 ppm and less than or equal to 3000 ppm in terms of volume fraction.

Abstract: A solar cell according to the present disclosure includes a support, a photoelectric conversion element, and a sealing member. The photoelectric conversion element is in a sealed space defined by the support and the sealing member. The photoelectric conversion element includes, in this order, a first electrode, a photoelectric conversion layer, and a second electrode. An oxygen concentration in the sealed space is less than 10 ppm in terms of volume fraction, and a water vapor concentration in the sealed space is greater than or equal to 100 ppm and less than or equal to 5000 ppm in terms of volume fraction.

Abstract: A solar battery of the present disclosure includes a first electrode; a photoelectric conversion layer; an intermediate layer; and a second electrode that are arranged in this order. The photoelectric conversion layer contains a perovskite compound. The intermediate layer contains a heterocyclic compound, the heterocyclic compound contains one or more and three or less six-membered rings, and at least one of the six-membered rings has 1-position and 4-position each occupied by an element having a lone pair.

Abstract: An ionizing radiation conversion device of the present disclosure includes a first electrode, a second electrode, and an ionizing radiation conversion layer disposed between the first electrode and the second electrode. Here, the first electrode contains a first metal, the second electrode contains at least one selected from the group consisting of second metals and metal oxides, and the ionizing radiation conversion layer contains a perovskite compound. The difference of a value of electron affinity of the ionizing radiation conversion layer minus a value of work function of the first electrode is greater than or equal to 0 eV and less than or equal to 0.4 eV.

Abstract: A solar cell includes a first electrode, an intermediate layer, a photoelectric conversion layer, and a second electrode in this order. The intermediate layer contains at least one compound A selected from predefined compound group I and at least one compound B selected from predefined compound group II.

Abstract: A solar cell includes a first electrode, a first electron transport layer, a second electron transport layer, a photoelectric conversion layer, and a second electrode. The first electron transport layer includes carbon and a porous electron transport material.

Abstract: The solar cell of the present disclosure includes a first electrode, a photoelectric conversion layer, an intermediate layer, a hole transport layer, and a second electrode in this order, wherein the hole transport layer includes a hole transport material and an oxidant, the photoelectric conversion layer includes a perovskite compound containing iodine, and the intermediate layer includes at least one selected from the group consisting of bromide, chloride, and fluoride.

Abstract: A light-absorbing material contains a compound represented by the composition formula HC(NH2)2SnI3 and having a perovskite structure. A solid-state 1H-NMR spectrum, which is obtained by 1H-14N HMQC measurement in two-dimensional NMR at 25° C., of the compound includes a first peak at 6.9 ppm and a second peak at 7.0 ppm. A peak intensity of the first peak is equal to 80% or more of a peak intensity of the second peak.

Abstract: The present disclosure provides a photoabsorber which has a perovskite crystal structure and is represented by the composition formula ABX3, wherein A is a monovalent cation including formamidinium cation A1 and a nitrogen-containing cation A2; the nitrogen-containing cation A2 has a larger ionic radius than the formamidinium cation A1; B is a divalent cation including a Sn cation; and X is a halogen anion. The photoabsorber according to the present disclosure improves conversion efficiency of the perovskite solar cell.

Abstract: A light-absorbing material contains a compound represented by the composition formula HC(NH2)2SnI3 and having a perovskite structure. A solid-state 1H-NMR spectrum, which is obtained by 1H-14N HMQC measurement in two-dimensional NMR at 25° C., of the compound includes a first peak at 6.9 ppm and a second peak at 7.0 ppm. A peak intensity of the first peak is equal to 80% or more of a peak intensity of the second peak.

Abstract: A method for reducing carbon dioxide is provided. In the present method, used is an anode electrode comprises a stacked structure of a photoelectric conversion layer, a metal layer, and an InxGa1-xN layer (where 0<x?1). The InxGa1-xN layer is of i-type or n-type. The metal layer is interposed between the photoelectric conversion layer and the InxGa1-xN layer. When irradiating the anode electrode with light, a first light part included in the light is absorbed by the InxGa1-xN layer and a second light part included in the light travels through the InxGa1-xN layer. The second light part is absorbed by the photoelectric conversion layer to generate electric power in the photoelectric conversion layer. The second light part has a longer wavelength than the first light part. The carbon dioxide contained in the first electrolyte solution is reduced on the cathode electrode.

Abstract: The present invention provides a method for splitting water. In the present method, first, prepared is a water splitting device comprising: cathode and anode containers in which first and second electrolyte solutions are stored respectively; a proton exchange membrane disposed therebetween; a cathode electrode in contact with the first electrolyte solution and comprises a metal or metal compound; and an anode electrode in contact with the second electrolyte solution and comprises a nitride semiconductor layer. Then, the anode electrode is irradiated with light to split water contained in the first electrolyte solution. The anode electrode comprises a cobalt oxide layer formed of Co3O4 as a main component on a surface of the nitride semiconductor layer; the surface of the nitride semiconductor layer being in contact with the second electrolyte solution. The cathode electrode is electrically connected to the anode electrode without an external power supply.

Abstract: The present disclosure provides a fuel production method and a fuel production apparatus which efficiently convert solar light energy into a fuel. The fuel production apparatus of the present disclosure includes a laminate, an electrolytic bath, and a support tool or a proton permeable membrane. The laminate includes a photoelectromotive layer having a p-n junction structure, a cathode electrode, an anode electrode and a side surface insulating layer, and the photoelectromotive layer includes a semiconductor layer that absorbs light in a near-infrared region with a wavelength of 900 nm or more.

Abstract: The present invention provides a method for splitting water. In the present method, first, prepared is a water splitting device comprising: cathode and anode containers in which first and second electrolyte solutions are stored respectively; a proton exchange membrane disposed therebetween; a cathode electrode in contact with the first electrolyte solution and comprises a metal or metal compound; and an anode electrode in contact with the second electrolyte solution and comprises a nitride semiconductor layer. Then, the anode electrode is irradiated with light to split water contained in the first electrolyte solution. The anode electrode comprises a cobalt oxide layer formed of Co3O4 as a main component on a surface of the nitride semiconductor layer; the surface of the nitride semiconductor layer being in contact with the second electrolyte solution. The cathode electrode is electrically connected to the anode electrode without an external power supply.

Abstract: In a method for generating formic acid by reducing carbon dioxide, a formic acid generation apparatus is prepared. The apparatus includes: a cathode container for storing a first electrolyte solution containing carbon dioxide; an anode container for storing a second electrolyte solution; a solid electrolyte membrane sandwiched between the cathode and anode containers; a cathode electrode provided in the cathode container in contact with the first electrolyte solution, the cathode electrode having a gallium oxide region on a surface thereof; an anode electrode provided in the anode container in contact with the second electrolyte solution; and an external power supply for applying a negative voltage and a positive voltage to the cathode electrode and the anode electrode, respectively. A negative voltage and a positive voltage are applied to the cathode electrode and the anode electrode, respectively, using the external power supply to generate formic acid on the cathode electrode.

Abstract: A method for reducing carbon dioxide is provided. In the present method, used is an anode electrode comprises a stacked structure of a photoelectric conversion layer, a metal layer, and an InxGa1-xN layer (where 0<x?1). The InxGa1-xN layer is of i-type or n-type. The metal layer is interposed between the photoelectric conversion layer and the InxGa1-xN layer. When irradiating the anode electrode with light, a first light part included in the light is absorbed by the InxGa1-xN layer and a second light part included in the light travels through the InxGa1-xN layer. The second light part is absorbed by the photoelectric conversion layer to generate electric power in the photoelectric conversion layer. The second light part has a longer wavelength than the first light part. The carbon dioxide contained in the first electrolyte solution is reduced on the cathode electrode.

Abstract: The present invention provides a formic acid generation apparatus for generating formic acid by reducing carbon dioxide, comprising: a cathode container for storing a first electrolyte solution containing carbon dioxide; an anode container for storing a second electrolyte solution; a solid electrolyte membrane sandwiched between the cathode container and the anode container; a cathode electrode provided in the cathode container so as to be in contact with the first electrolyte solution, the cathode electrode having a gallium oxide region on a surface thereof; an anode electrode provided in the anode container so as to be in contact with the second electrolyte solution; and an external power supply for applying a negative voltage and a positive voltage to the cathode electrode and the anode electrode, respectively.

Abstract: Provided is a biogas generation system comprising a fermenter for generating a biogas containing carbon dioxide and methane by decomposing an organic waste by the action of methane bacteria; a biogas refinery for condensing the methane contained in the biogas by dissolving the carbon dioxide contained in the generated biogas in a liquid; and a photoelectrochemical device for generating methane, carbon monoixide, or formic acid from the carbon dioxide dissolved in the liquid. The photoelectrochemical device comprises a cathode chamber for storing a first electrolyte solution containing the carbon dioxide dissolved in the liquid; an anode chamber for storing a second electrolyte solution; a solid electrolyte membrane; a cathode electrode provided in the cathode chamber; an anode electrode provided in the anode chamber; and an external power supply for applying a negative voltage and a positive voltage to the cathode electrode and the anode electrode, respectively.

Abstract: Disclosed is a solar cell which allows more photogenerated carriers to be extracted while improving power generation efficiency. The solar cell has a light-receiving surface electrode layer (2), a first photoelectric conversion unit (31) layered over the light-receiving surface electrode layer (2), a reflective layer (32) comprising SiO and layered over the first photoelectric conversion unit (31), a second photoelectric conversion unit (33) layered over the reflective layer (32), and a backside electrode layer (4) layered over the second photoelectric conversion unit (33). An oxygen concentration of the reflective layer (32) is higher on a side of the second photoelectric conversion unit (33) than on a side of the first photoelectric conversion unit (31).