A photovoltaic cell is provided that enables cost reduction and stable operation with a simple configuration and enhances conversion efficiency by a new technology of forming an energy level in a band gap. In the photovoltaic cell, a substrate, a conductive first electrode, an electromotive force layer, a p-type semiconductor layer, and a conductive second electrode are laminated, electromotive force is generated by photoexciting the electron in the band gap of the electromotive force layer by light irradiation, the electromotive force layer is filled with an n-type metal oxide semiconductor of fine particles coated by an insulating coat, a new energy level is formed in a band gap by photoexcited structural change caused by ultraviolet irradiation, and efficient and stable operation can be performed by providing a layer of an n-type metal oxide semiconductor between the first electrode and the electromotive force layer.

A method for passivating the surface of crystalline iron disulfide (FeS.sub.2) by encapsulating it in crystalline zinc sulfide (ZnS). Also disclosed is the related product comprising FeS.sub.2 encapsulated by ZnS in which the sulfur atoms at the FeS.sub.2 surfaces are passivated. Additionally disclosed is a photovoltaic (PV) device incorporating FeS.sub.2 encapsulated by ZnS.

The performance of lead sulfide quantum dot (QD) photovoltaic cells is improved by exposing a QD layer to a solution containing metal salts after the synthesis of the QDs is completed. The halide ions from the salt solution passivate surface lead (Pb) sites and alkali metal ions mend Pb vacancies. Metal cations and halide anions with small ionic radius have high probability of reaching QD surfaces to eliminate surface recombination sites. Compared to control devices fabricated using only a ligand exchange procedure without salt exposure, devices with metal salt treatment show increases in both the form factor and short circuit current of the PV cell. Some embodiments comprise a method for treatment of QDs with a salt solution and ligand exchange. Other embodiments comprise a photovoltaic cell having a QD layer treated with a salt solution and ligand exchange.

Radiation detecting-structures and fabrications methods thereof are presented. The methods include, for instance: providing a substrate, the substrate including at least one trench extending into the substrate from an upper surface thereof; and epitaxially forming a radiation-responsive semiconductor material layer from one or more sidewalls of the at least one trench of the substrate, the radiation-responsive semiconductor material layer responding to incident radiation by generating charge carriers therein. In one embodiment, the sidewalls of the at least one trench of the substrate include a (111) surface of the substrate, which facilitates epitaxially forming the radiation-responsive semiconductor material layer. In another embodiment, the radiation-responsive semiconductor material layer includes hexagonal boron nitride, and the epitaxially forming includes providing the hexagonal boron nitride with an a-axis aligned parallel to the sidewalls of the trench.

A hybrid organic-inorganic thin film is provided. The hybrid organic-inorganic thin film comprising: an organic-phase comprising a porous organic nanostructure comprised of an interpenetrating network having at least one dimension between 0.1 and 100 nm; and an inorganic phase at least partially distributed within the porosity of the organic phase. In a first aspect, the organic phase has a first band gap and the inorganic phase has a second band gap different from the first band gap. A method of producing an organic-inorganic energy harvesting device and a device therefrom comprising the hybrid organic-inorganic thin film is provided.

A composite material for fluorescent quantum dot micro-nano packaging. The composite material comprises fluorescent quantum dots, a mesoporous particle material having a nanometer lattice structure, and a barrier layer, wherein the fluorescent quantum dots are distributed in the mesoporous particle material, and the barrier layer is coated on the outer surface of the mesoporous particle material. In the composite material according to the invention, the quantum dot aggregation can be effectively retarded, with the barrier layer coated on the surface the water-oxygen micromolecule erosion is prevented, the compatibility and stability of the composite fluorescent particles is improved, and the service life of the composite material for fluorescent quantum dot micro-nano packaging is thus greatly improved.

An X-ray detector according to the present disclosure comprises: a scintillator for converting incident X-rays into visible rays; a photoelectric conversion part, which is disposed below the scintillator and converts the visible rays into electrical signals; and a substrate disposed below the photoelectric conversion part, wherein the scintillator comprises a perovskite compound represented by the following chemical formula 1. [Chemical Formula 1] A.sub.3B.sub.2X.sub.5:Activator (In the chemical formula, A is a monovalent metal cation, B is a divalent metal cation, X is a monovalent anion, and the activator is thallium (Tl) or indium (In).)

An X-ray detector according to the present disclosure comprises: a scintillator for converting incident X-rays into visible rays; a photoelectric conversion part, which is disposed below the scintillator and converts the visible rays into electrical signals; and a substrate disposed below the photoelectric conversion part, wherein the scintillator comprises a perovskite compound represented by the following chemical formula 1. [Chemical Formula 1] A.sub.3B.sub.2X.sub.5:Activator (In the chemical formula, A is a monovalent metal cation, B is a divalent metal cation, X is a monovalent anion, and the activator is thallium (Tl) or indium (In).)

Plasmonic substrates are provided which may be used in a variety of optoelectronic devices, e.g., biosensors and photodetectors. The plasmonic substrate may comprise a layer of graphene and a plurality of discrete, individual transition metal chalcogenide nanodomes distributed on a surface of the layer of graphene, each nanodome surrounded by bare graphene. Methods for making and using the plasmonic substrates are also provided.

A light-receiving device includes graphene including a light-receiving part; major electrodes electrically connected with the graphene, the major electrodes including a source electrode and a drain electrode, the light-receiving part being positioned between the source electrode and the drain electrode; a gate electrode electrically connected with the light-receiving part of the graphene via capacitive coupling; a circuit part electrically connected with the major electrode and the gate electrode; and an ionic substance contacting the light-receiving part of the graphene. The ionic substance is one of an anion having an acid dissociation constant of not less than 3 or a cation having an acid dissociation constant of not more than 11.