A repeat unit comprising

##STR00001##

In the repeat unit, X.sub.1 and X.sub.2 are independently selected from the group consisting of: F, Cl, H, and combinations thereof. Additionally, in this monomer, R′ and R″ are independently selected from an alkyl group, an aryl group, or combinations thereof. Also, R.sub.3, and R.sub.4 are independently selected from unsubstituted or substituted branched alkyls with 1 to 60 carbon atoms and unsubstituted or substituted linear alkyls with 1 to 60 carbon atoms.

A photoelectric conversion device includes a first electrode and a second electrode facing each other, an organic photoelectric conversion layer between the first electrode and the second electrode, and a charge auxiliary layer between the first electrode and the organic photoelectric conversion layer. The organic photoelectric conversion layer is configured to absorb light in at least a portion of a wavelength spectrum of incident light and to convert the absorbed light into an electrical signal. The charge auxiliary layer includes a metal and an oxide. The oxide may be an oxide material that excludes silicon oxide such that the charge auxiliary layer does not include silicon oxide.

A phototransistor device to act as an artificial photonic synapse includes a substrate and a graphene source-drain channel patterned on the substrate. A perovskite quantum dot layer is formed on the graphene source-drain channel. The perovskite quantum dot layer is methylammonium lead bromide material. A method of operating the phototransistor device as an artificial photonic synapse includes applying a first fixed voltage to a gate of the phototransistor and a second fixed voltage across the graphene source-drain channel. A presynaptic signal is applied as stimuli across the graphene source-drain channel. The presynaptic signal includes one or more pulses of light or electrical voltage. A current across the graphene source-drain channel is measured to represent a postsynaptic signal.

An organic photoelectric conversion device and an image sensor, the organic photoelectric conversion device including an upper electrode; a lower electrode; and an active layer between the upper electrode and the lower electrode, wherein the active layer includes bis-(4-dimethylaminodithiobenzyl)-Ni(II) (BDN) and [6,6]-Phenyl-C71-butyric acid methyl ester (PC70BM).

An organic photoelectric conversion device and an image sensor, the organic photoelectric conversion device including an upper electrode; a lower electrode; and an active layer between the upper electrode and the lower electrode, wherein the active layer includes bis-(4-dimethylaminodithiobenzyl)-Ni(II) (BDN) and [6,6]-Phenyl-C71-butyric acid methyl ester (PC70BM).

Organic-inorganic light-absorbing materials with perovskite structure, being used in perovskite solar cells production. The objective of the invention is to provide the possibility of obtaining perovskite using precursors that are in a liquid state without the use of additional substances and reagents. The concept of the invention is based on the fact that a light-absorbing material with perovskite structure with general formula ADB.sub.3, where A stands for methylammonium MA.sup.+ (CH.sub.3NH.sub.3.sup.+), formamidinium, FA.sup.+ ((NH.sub.2).sub.2CH.sup.+), guanidinium Gua (C(NH2)3+), cesium Cs.sup.+ or a mixture thereof, B stands for Cl.sup.−, Br.sup.−, I.sup.− or a mixture thereof, while the component D represents Sn, Pb, Bi or a mixture thereof, is obtained by mixing composition AB-nB.sub.2 and a component containing D, where the component containing D is chosen from elemental Sn, Pb, Bi and/or their salts, mixtures, alloys, whereas the composition AB-nB.sub.2 is deposited onto the component D followed by subsequent removal of the excessive components, n is greater than or equal to one, the component B.sub.2 represents Cl.sub.2, Br.sub.2, I.sub.2 or a mixture thereof.

An organic photodiode includes a first electrode including a reflective layer, a second electrode including a semi-transmissive layer, a photoelectric conversion layer between the first electrode and the second electrode and including an organic light absorbing material, and a buffer layer that is at least one of between the reflective layer and the photoelectric conversion layer or between the semi-transmissive layer and the photoelectric conversion layer. The organic photodiode is configured to exhibit at least three external quantum efficiency (EQE) spectra in a wavelength region of about 380 nm to about 3000 nm and each EQE spectrum of the at least three EQE spectra has a full width at half maximum of about 2 nm to about 100 nm.

A photovoltaic device includes a first group of photovoltaic cells of a first cell type, the first group of photovoltaic cells operable to produce a first current and a first voltage, and a second group of photovoltaic cells of a second cell type that is different than the first cell type, the second group of photovoltaic cells operable to produce a second current and a second voltage. A first power electronics unit is connected to the first group of photovoltaic cells, and a second power electronics unit is connected to the second group of photovoltaic cells. The second power electronics unit is separate from and not communicating with the first power electronics unit. A control device is operable to vary a first property of the first power electronics unit to vary the first current and the first voltage and to vary a second property of the second power electronics unit to vary the second voltage and the second current independent of the first voltage and the first current.

A method of manufacturing a lead salt thin film on a substrate by seeding a substrate with a lead salt solution (e.g., PbSe, PbS, or PbTe) to form a seeded substrate comprising lead salt seed crystals, and growing the lead salt thin film upon the substrate by exposing the seeded substrate to a chemical bath comprising the lead salt solution at a predetermined growth temperature. A lead salt thin film manufactured by the process. A photonic crystal microchip comprising the lead salt thin film. A gas sensing device comprising a diode laser, a mid-infrared photodetector, and the photonic crystal microchip. A method of detecting a hydrocarbon gas, comprising exposing a gas sample to the gas sensing device, and determining the content of hydrocarbon gases in the gas sample.

A light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode and including an emission layer, wherein the interlayer includes a heterocyclic compound of Formula 1:

A.sub.1B.sub.1].sub.n1  Formula 1

wherein, in Formula 1, the variables are defined herein.