The present invention provides a triple-junction photovoltaic device comprising three photoactive regions, each photoactive region comprising a perovskite material. A second sub-cell is comprised of a photoactive perovskite layer deposited directly onto a first sub-cell comprising a photoactive perovskite layer, creating a monolithically integrated device with two external electrical contacts (2T). A third sub-cell comprising a photoactive perovskite layer, engineered independently with two external electrical contacts, is stacked onto the second sub-cell of the monolithically integrated device, creating a novel triple-junction all-perovskite photovoltaic device with four external electrical contacts (4T). Also provided is a method of constructing a triple-junction all-perovskite photovoltaic device with four external electrical contacts and a method for perovskite material formation comprising inclusion of the organic stress-inducing compounds metformin and berberine to enhance perovskite crystal formation, stability, and perovskite solar cell efficiency.

The present invention relates to an optoelectronic device including an electron transport layer (ETL) and a light harvesting layer, wherein the light harvesting layer includes a metal halide perovskite and is provided on the ETL being a multilayer structure having at least two layers of metal oxide, at least one layer of which includes a crystalline mesoporous metal oxide and at least one layer of which includes an amorphous metal oxide or metal oxide nanocrystals, and wherein the layer being in contact with the light harvesting layer includes the amorphous metal oxide or the metal oxide nanocrystals and is provided on the layer including the crystalline mesoporous metal oxide.

To improve detectivity of a photoelectric conversion element (10). A photoelectric conversion element including a pair of electrodes (12, 16), an active layer (14) provided between the pair of electrodes, and an intermediate layer (13. 15) provided between the active layer and at least one of the pair of electrodes, in which the intermediate layer has a surface that is in contact with the active layer, the surface having a surface roughness having an absolute value greater than 0.22 nm but smaller than 1.90 nm, and in which the active layer is not less than 350 nm but not more than 800 nm in thickness.

A thin film of metal oxide includes zinc (Zn); tin (Sn); silicon (Si); and oxygen (O). In terms of oxide, based on 100 mol % of total of oxides of the thin film, SnO.sub.2 is greater than 15 mol % but less than or equal to 95 mol %.

A PIN type infrared photodiode including a first electrode, a n-type semiconductor, an atomic layer deposition coating of lead sulfide, a p-type semiconductor and a second electrode, wherein the n-type semiconductor comprises nanowires conformally coated with the atomic layer deposition coating of lead sulfide.

Disclosed are a monolithic solar cell and a method of manufacturing the same. More particularly, the present invention provides a monolithic solar cell including a first solar cell formed by sequentially stacking an electrode, a silicon substrate, and an n-type emitter layer; a junction layer formed on the an n-type emitter layer; an interfacial layer formed on the junction layer; and a second solar cell including a perovskite layer and integrated onto the interfacial layer. The interfacial layer according to the present invention may be pyrolyzed and thus partially or completely lost during a monolithic solar cell manufacturing process. In addition, by providing an interfacial layer between the two cells constituting a monolithic solar cell according to the present invention, charge transfer and recombination characteristics between the two cells can be improved and thus a monolithic solar cell having significantly improved photoelectric conversion efficiency can be provided.

An organic photovoltaic cell comprises a first electrode, a second electrode, an active layer comprising at least one donor material and at least one acceptor material, positioned between the first electrode and the second electrode, an outcoupling layer positioned on a surface of the first electrode such that the first electrode is positioned between the outcoupling layer and the active layer, and an anti-reflective coating positioned over a surface of the second electrode such that the second electrode is positioned between the anti-reflective coating and the active layer, wherein the organic photovoltaic cell is at least semi-transparent to at least one wavelength range. A method of fabricating an organic device is also described.

Provided is a photoelectric conversion element including a first electrode, a hole blocking layer, an electron transport layer, a first hole transport layer, and a second electrode, wherein the first hole transport layer includes at least one of basic compounds represented by general formula (1a) and general formula (1b) below:

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where in the formula (1a) or (1b), R.sub.1 and R.sub.2 represent a substituted or unsubstituted alkyl group or aromatic hydrocarbon group and may be identical or different, and R.sub.1 and R.sub.2 may bind with each other to form a substituted or unsubstituted heterocyclic group containing a nitrogen atom.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

An opto-electronic device includes a first electrode, a first buffer layer formed on the first electrode, and a perovskite semiconductor active layer formed on the first buffer layer. The opto-electronic device further includes a second buffer layer formed on the perovskite semiconductor active layer, and a second electrode formed on the second buffer layer. The first buffer layer, the second buffer layer, and the perovskite semiconductor active layer each consists essentially of inorganic materials.