A method of forming a Pb-free perovskite film is provided, the method based on vacuum evaporation and comprising: first depositing a first material comprising Sn halide on a substrate to form a first layer; second depositing a second material comprising organic halide to form a second layer on the first layer to obtain a sequentially-deposited two-layer film on the substrate; and annealing the sequentially-deposited two-layer film on the substrate. During the annealing, the first and second materials inter-diffuse and react to form the Pb-free perovskite film. The second layer is formed to cover the first layer so as to prevent the first layer from air exposure. The solar cell device including the Pb-free perovskite film formed by using the present method exhibits good stability.

The present disclosure relates to a rhythmic deposition production method and equipment of a perovskite thin film. The method includes the followings: a to-be-deposited substrate pre-prepared with a precursor BX.sub.2 thin film containing a perovskite precursor BX.sub.2 material is placed into a deposition-reaction chamber for evaporating and depositing a precursor AX material; the deposition is suspended after a period of time such that the precursor AX material deposited on a surface of the precursor BX.sub.2 thin film has sufficient time to diffuse into the precursor BX.sub.2 thin film so as to form a perovskite ABX.sub.3 crystal; after a period of suspension, deposition is performed again, such that the deposition and suspension processes are alternately repeated rhythmically and the AX material enters the BX.sub.2 thin film to fully react with the BX.sub.2 material, so as to obtain an ABX 3 perovskite crystal without BX.sub.2 material residual or with AX material surplus, until a perovskite ABX.sub.3 thin film with a set thickness is obtained. Thus the rhythmic deposition process is ended. The present disclosure further provides an equipment using the method. In the present disclosure, continuous large-area production of the perovskite thin film is realized with high reliability and repeatability.

The present disclosure relates to a rhythmic deposition production method and equipment of a perovskite thin film. The method includes the followings: a to-be-deposited substrate pre-prepared with a precursor BX.sub.2 thin film containing a perovskite precursor BX.sub.2 material is placed into a deposition-reaction chamber for evaporating and depositing a precursor AX material; the deposition is suspended after a period of time such that the precursor AX material deposited on a surface of the precursor BX.sub.2 thin film has sufficient time to diffuse into the precursor BX.sub.2 thin film so as to form a perovskite ABX.sub.3 crystal; after a period of suspension, deposition is performed again, such that the deposition and suspension processes are alternately repeated rhythmically and the AX material enters the BX.sub.2 thin film to fully react with the BX.sub.2 material, so as to obtain an ABX 3 perovskite crystal without BX.sub.2 material residual or with AX material surplus, until a perovskite ABX.sub.3 thin film with a set thickness is obtained. Thus the rhythmic deposition process is ended. The present disclosure further provides an equipment using the method. In the present disclosure, continuous large-area production of the perovskite thin film is realized with high reliability and repeatability.

According to one embodiment, a photovoltaic cell device includes a transparent substrate including a first main surface and a second main surface opposed to the first main surface, a liquid crystal layer disposed on the second main surface side of the transparent substrate and including a cholesteric liquid crystal including liquid crystal molecules, and photovoltaic cells disposed on at least one of the first main surface side and the second main surface side of the transparent substrate, each formed into a strip shape, and arranged with a predetermined gap between the photovoltaic cells.

According to one embodiment, a photovoltaic cell device includes a transparent substrate including a first main surface and a second main surface opposed to the first main surface, a liquid crystal layer disposed on the second main surface side of the transparent substrate and including a cholesteric liquid crystal including liquid crystal molecules, and photovoltaic cells disposed on at least one of the first main surface side and the second main surface side of the transparent substrate, each formed into a strip shape, and arranged with a predetermined gap between the photovoltaic cells.

An organic photovoltaic device is provided. The organic photovoltaic device includes an active layer having an organic photoactive component having a water contact angle of greater than or equal to about 65. Methods of making the organic photovoltaic device are also provided.

A light detection element including: a carbon nanotube structure; a first electrode and a second electrode, electrically connected to the carbon nanotube structure; wherein the carbon nanotube structure includes at least one carbon nanotube, the carbon nanotube includes two metallic carbon nanotube segments and one semiconducting carbon nanotube segment between the two metallic carbon nanotube segments, one of the two metallic carbon nanotube segments is electrically connected to the first electrode, the other one of the two metallic carbon nanotube segments is electrically connected to the second electrode.

A method for making a polymer solar cell includes the following steps: placing a portion of a carbon nanotube layer into a polymer solution, wherein the carbon nanotube layer includes a plurality of carbon nanotubes; curing the polymer solution to form a polymer layer including a first polymer surface and a second polymer surface opposite to the first polymer surface, wherein the portion of the carbon nanotube layer is embedded in the polymer layer, and another portion of the carbon nanotube layer is exposed from the polymer layer; and forming a cathode electrode on a surface of the carbon nanotube layer away from the polymer layer, and forming an anode electrode on the first polymer surface, wherein the anode electrode is spaced apart from the carbon nanotube layer.

A photoelectric conversion material includes a compound represented by Formula (1):

##STR00001##

where, X is selected from the group consisting of a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, and a cyano group; and Y represents a monovalent substituent represented by Formula (2):

##STR00002##

where, R.sub.1 to R.sub.10 each independently represent a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, or an aryl group; or two or more of R.sub.1 to R.sub.10 bond to each other to form one or more rings, and the remainders each independently represent a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, or an aryl group; * denotes the binding site of Y in Formula (1); and Ar.sub.1 is selected from the group consisting of structures represented by Formulae (3):

##STR00003##

where ** denotes a binding site of Ar.sub.1 with N in Formula (2).

A polymer solar cell includes an anode electrode, a photoactive layer, and a cathode electrode stacked on each other in that order. The photoactive layer includes a polymer layer and a plurality of carbon nanotubes dispersed in the polymer layer. Each of the plurality of carbon nanotubes includes a first carbon nanotube portion and a second carbon nanotube portion. The first carbon nanotube portion is embedded in the polymer layer, and the second carbon nanotube portion is exposed out of the polymer layer and directly contacts the cathode electrode.