Disclosed are a hybrid structure using a graphene-carbon nanotube and a perovskite solar cell using the same. The hybrid structure includes a graphene-carbon nanotube formed by laminating a second graphene coated with a polymer on an upper surface of a first graphene coated with a carbon nanotube. The perovskite solar cell includes: a substrate; a first electrode formed on the substrate and including a fluorine doped thin oxide (FTO); an electron transfer layer formed on the first electrode and including a compact-titanium oxide (c-TiO.sub.2); a mesoporous-titanium oxide (m-TiO.sub.2) formed on the electron transfer layer; a perovskite layer formed on the m-TiO.sub.2 and including a perovskite compound; and a graphene-carbon nanotube hybrid structure formed on the perovskite layer.

The present invention relates to a method for obtaining a photovoltaic CZTS thin-film solar cell including arranging a precursor solution, preparing a substrate, and depositing said precursor solution on said substrate.

A layer structure for a thin-film solar cell and production method are provided. The layer structure for the thin-film solar cell includes a photovoltaic absorber layer doped, at least in a region which borders a surface of the photovoltaic absorber layer, with at least one alkali metal. The layer structure has an oxidic passivating layer on the surface of the photovoltaic absorber layer, which is designed to protect the photovoltaic absorber layer from corrosion.

A layer structure for a thin-film solar cell and production method are provided. The layer structure for the thin-film solar cell includes a photovoltaic absorber layer doped, at least in a region which borders a surface of the photovoltaic absorber layer, with at least one alkali metal. The layer structure has an oxidic passivating layer on the surface of the photovoltaic absorber layer, which is designed to protect the photovoltaic absorber layer from corrosion.

A method for preparing a solar cell, includes: forming a first electrode on a substrate; forming a light absorbing layer on the first electrode; and forming a second electrode on the light absorbing layer, wherein the method further comprises forming an impurity material layer including an impurity element on the light absorbing layer adjacent to the first electrode or the second electrode in any one side or both sides thereof, and forming a doping layer by diffusing the impurity element into a portion of the light absorbing layer.

Disclosed are a hybrid structure using a graphene-carbon nanotube and a perovskite solar cell using the same. The hybrid structure includes a graphene-carbon nanotube formed by laminating a second graphene coated with a polymer on an upper surface of a first graphene coated with a carbon nanotube. The perovskite solar cell includes: a substrate; a first electrode formed on the substrate and including a fluorine doped thin oxide (FTO); an electron transfer layer formed on the first electrode and including a compact-titanium oxide (c-TiO.sub.2); a mesoporous-titanium oxide (m-TiO.sub.2) formed on the electron transfer layer; a perovskite layer formed on the m-TiO.sub.2 and including a perovskite compound; and a graphene-carbon nanotube hybrid structure formed on the perovskite layer.

A method for preparing a solar cell, includes: forming a first electrode on a substrate; forming a light absorbing layer on the first electrode; and forming a second electrode on the light absorbing layer, wherein the method further comprises forming an impurity material layer including an impurity element on the light absorbing layer adjacent to the first electrode or the second electrode in any one side or both sides thereof, and forming a doping layer by diffusing the impurity element into a portion of the light absorbing layer.

Photovoltaic devices based on an Ag.sub.2ZnSn(S,Se).sub.4 (AZTSSe) absorber and techniques for formation thereof are provided. In one aspect, a method for forming a photovoltaic device includes the steps of: coating a substrate with a conductive layer; contacting the substrate with an Ag source, a Zn source, a Sn source, and at least one of a S source and a Se source under conditions sufficient to form an absorber layer on the conductive layer having Ag, Zn, Sn, and at least one of S and Se; and annealing the absorber layer. Methods of doping the AZTSSe are provided. A photovoltaic device is also provided.

Techniques for increasing grain size in AZTSSe absorber materials are provided. In one aspect, a method for forming an absorber film on a substrate includes: contacting the substrate with an Ag source, a Zn source, a Sn source, and an S source and/or an Se source under conditions sufficient to form the absorber film on the substrate having a target composition of: Ag.sub.XZn.sub.YSn(S,Se).sub.Z, wherein 1.7<x<2.2, 0.9<y<1.3, and 3.5<z<4.5, and including an amount of the Ag source that is from about 10% to about 30% greater than is needed to achieve the target composition; annealing the absorber film; and removing excess Ag from the absorber film. A solar cell and method for fabrication thereof are also provided.

A photovoltaic device includes a first contact layer formed on a substrate. An absorber layer includes CuZnSnS(Se) (CZTSSe) on the first contact layer. A buffer layer is formed in contact with the absorber layer. Metal dopants are dispersed in a junction region between the absorber layer and the buffer layer. The metal dopants have a valence between the absorber layer and the buffer layer to increase junction potential. A transparent conductive contact layer is formed over the buffer layer.