A method for preparing photoactive perovskite materials. The method comprises the step of preparing a germanium halide precursor ink. Preparing a germanium halide precursor ink comprises the steps of: introducing a germanium halide into a vessel, introducing a first solvent to the vessel, and contacting the germanium halide with the first solvent to dissolve the germanium halide. The method further comprises depositing the germanium halide precursor ink onto a substrate, drying the germanium halide precursor ink to form a thin film, annealing the thin film, and rinsing the thin film with a second solvent and a salt.

A photovoltaic device (10) is provided that comprises serially arranged photovoltaic device cells (10A, 10B). Each cell having a transparent electrode layer region electrical conductors (121A, . . . , 124A) forming an electric contact with the transparent electrode layer region, a photo-voltaic stack portion (14A, 14B) that extends over the transparent electrode region (11A, 11B) and over an insulated portion of the electrical conductors, a further electrode region (15A, 5B) that extends over the photovoltaic stack portion (14A,14B). A further electrode region (15A) of a photovoltaic device cell (10A) extends over electric contacts formed by exposed ends (12B1) of the electrical conductors of a subsequent photovoltaic device cell (10B).

The present invention provides a novel method for producing a laminate to be used as a light-transmissive electrode layer and an N-type semiconductor layer of a wet or solid-state dye-sensitized solar cell comprising a light-transmissive electrode layer, an N-type semiconductor layer, a P-type semiconductor layer, and a facing electrode in this order. In said method, a member to be used as the light-transmissive electrode layer is cathode-polarized in a treatment solution containing a Ti component so as to form a titanium oxide layer to be used as the N-type semiconductor layer on said member.

According to one embodiment, a photovoltaic cell module includes a light guide including a first main surface, a second main surface, a first side surface, a second side surface, a third side surface and a fourth side surface, an optical element opposing the second main surface, containing a cholesteric liquid crystal forming a reflective surface inclined with respect to the second main surface, and configured to reflect at least a part of light entering from the first main surface toward the light guide, a photovoltaic cell opposing the first side surface and a reflective member opposing the second side surface, the third side surface and the fourth side surface.

The light conversion efficiency of a solar cell is enhanced by using an optical downshifting layer in cooperation with a photovoltaic material. The optical downshifting layer converts photons having wavelengths in a supplemental light absorption spectrum into photons having a wavelength in the primary light absorption spectrum of the photovoltaic materiaL The cost effectiveness and efficiency of solar cells platforms can be increased by relaxing the range of the primary light absorption spectrum of the photovoltaic materiaL The optical downshifting layer can be applied as a low cost solution processed film composed of highly absorbing and emissive quantum dot heterostructure nanomaterial embedded in an inert matrix to improve the short wavelength response to the photovoltaic materiaL The enhanced efficiency provided by the optical downshifting layer permits advantageous modifications to the solar cell platform that enhances its efficiency as well.

A photoelectric conversion device includes: a substrate; a first photoelectric conversion element including a first substrate electrode, a first active layer and a first counter electrode; a second photoelectric conversion element including a second substrate electrode, a second active layer, and a second counter electrode; and a connection connecting the first counter electrode and the second substrate electrode. The second active layer is represented by a composition formula: A.sub.αBX.sub.χ, where A denotes at least one cation selected from monovalent cations, B denotes at least one cation selected from bivalent cations, and X denotes at least one ion selected from monovalent halogen ions; and the second active layer has a first and a second compound layer, the first compound layer containing a first compound satisfying 0.95≤α, and 2.95≤χ, and the second compound layer containing a second compound satisfying α<0.95, and χ<2.95.

Forming a semiconductor device includes forming a first conductive line on a substrate, forming a memory cell including a switching device and a data storage element on the first conductive line, and forming a second conductive line on the memory cell. Forming the switching device includes forming a first semiconductor layer, forming a first doped region by injecting a n-type impurity into the first semiconductor layer, forming a second semiconductor layer thicker than the first semiconductor layer, on the first semiconductor layer having the first doped region, forming a second doped region by injecting a p-type impurity into an upper region of the second semiconductor layer, and forming a P-N diode by performing a heat treatment process to diffuse the n-type impurity and the p-type impurity in the first doped region and the second doped region to form a P-N junction of the P-N diode in the second semiconductor layer.

A negative active material includes a carbon material. The carbon material satisfies the following relationship: 6<Gr/K<16, Gr is a graphitization degree of the carbon material, measured by X-ray diffraction; and K is a ratio Id/Ig of a peak intensity Id of the carbon material at a wavenumber of 1250 cm.sup.−1 to 1650 cm.sup.−1 to a peak intensity Ig of the carbon material at a wavenumber of 1500 cm.sup.−1 to 1650 cm.sup.−1, and is measured by using Raman spectroscopy, and K is 0.06 to 0.15.

Provided is a photoelectric conversion device including: a support; a charge-transporting layer including an organic charge-transporting material or a sensitizing dye electrode layer including an organic sensitizing dye, where the charge-transporting layer or the sensitizing dye electrode layer is disposed on the support; and a ceramic film disposed on the charge-transporting layer or the sensitizing dye electrode layer.

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.