Techniques to Improve Carrier Mobility in Quantum Dot Solar Cells

Heterojunction PbS quantum dot solar cell with enhanced light absorption and charge collection through nanostructured PN junction layers. The cell features a stacked glass substrate with a nano-patterned PbS quantum dot layer, followed by a PN junction layer with ZnO nanoparticles as optical antennas. The ZnO nanoparticles serve as efficient light-harvesting materials while maintaining electronic inertness, enabling improved charge collection and filling factor. The nanostructured architecture enables efficient light absorption and carrier transport through the PbS quantum dot layer, while the PN junction layer enhances charge collection at the contact interface.

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Photoelectric conversion element with improved sensitivity and dynamic range through quantum dot-based light detection. The element comprises a photoelectric conversion layer comprising three or more quantum dot layers, each with surface-modifying ligands that modify the quantum dot surfaces. The quantum dot layers are arranged with specific bandgap energy relationships, where the energy of the quantum dot closer to the first electrode is smaller than the energy of the quantum dot closer to the second electrode. This arrangement enables the conversion of visible light into electrical signals across a broad spectral range, with the quantum dot energy matching the desired detection wavelength.

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Multi-intermediate band quantum dot solar cell with improved efficiency by using multiple quantum dot layers with different bandgaps to absorb a broader range of low-energy photons. The cell has a stack of quantum dot layers on an N-type semiconductor, each layer having a different bandgap. This allows absorption of sub-bandgap photons that cannot be absorbed by a single intermediate band. The layers are sandwiched between N-type and P-type semiconductors to form a solar cell.

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Broad-spectrum, high-absorptivity light absorption layer for solar cells with improved efficiency compared to conventional layers. The layer comprises a ferroelectric nanoparticle layer, a semiconductor quantum dot layer, and an underlying substrate. The ferroelectric nanoparticles and quantum dots absorb light across a wide spectrum. The ferroelectric nanoparticles have high absorption in the visible region, while the quantum dots absorb in the UV-blue range. This broadens the overall absorption spectrum compared to just quantum dots. The ferroelectric layer also improves light absorption by scattering and trapping light. The layer preparation involves depositing the layers using techniques like pulsed laser deposition.

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Solar cell with enhanced photoelectric conversion efficiency through the incorporation of carbon quantum dots. The solar cell comprises a metal electrode, hole transport layer, carbon quantum dot modified layer, calcium layer, electron transport layer, and transparent electrode. The carbon quantum dots are specifically designed to enhance charge carrier mobility and absorption in the solar cell's perovskite layer, leading to improved conversion efficiency.

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Solar cells with quantum-structured materials and/or layers of quantum-structured materials incorporated therein achieve high open circuit voltages through novel device architectures. The cells incorporate a wide band gap material in both the emitter and depletion region adjacent to the emitter, with a wider energy gap extended emitter structure featuring material in both the emitter and depletion region. This design enables improved carrier collection while minimizing dark current, particularly in optically-thin solar cells.

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Lead sulfide quantum dot/polymer hybrid solar cells that achieve high efficiency through controlled interface engineering. The hybrid cells incorporate an interface layer with thiol ligands between the lead sulfide quantum dots and polymer matrix, which enhances charge transport and optoelectronic properties. The interface layer selectively passesivates the quantum dot/polymer interface, reducing energy band bending and charge accumulation, while maintaining the quantum dot's photovoltaic properties. This approach enables near-infrared photovoltaic devices with improved charge transport characteristics compared to conventional lead sulfide solar cells.

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Intermediate tandem layer for photovoltaic devices that eliminates potential barrier layers between cells, thereby improving efficiency and open-circuit voltage. The layer comprises a barrier material and quantum dots dispersed within it, which are formed through controlled crystallization processes. This structure enables carrier tunneling recombination to be minimized by preventing the formation of reverse potential barriers between cells. The layer can be deposited between the upper and lower battery cells in a photovoltaic device.

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Quantum dot photovoltaic device with enhanced optoelectronic performance through improved electron transport layer preparation. The device comprises a conductive glass substrate, an electron transport layer, a quantum dot photosensitization absorption layer, and an anode. The electron transport layer is prepared by vacuum coating a zinc-doped metal oxide film onto the substrate, followed by spin coating a quantum dot photosensitization absorption layer. The device achieves improved electron transport layer properties by optimizing spin coating conditions, including speed and time, while maintaining the structural integrity of the zinc-doped metal oxide film.

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Solar cell with enhanced efficiency through selective hole transport through a quantum dot structure. The solar cell features a charge-selective emitter layer with a superlattice quantum dot structure that selectively passes electrons while allowing holes to pass through. This selective hole transport enables efficient separation of charge carriers, significantly reducing recombination losses and increasing overall solar cell efficiency.

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Photovoltaic junctions with improved optoelectronic properties through controlled synthesis of semiconductor and metal components. The junctions incorporate quantum dots as light-absorbing materials, with the dots dispersed as a thin film on the semiconductor acceptor surface. The acceptor material is engineered to have a slightly larger bandgap than the light-absorbing material, enabling efficient absorption across a broad spectral range. The junction architecture combines a light-absorbing material with a semiconductor acceptor and a metallic contact, enabling efficient charge collection while maintaining optoelectronic performance.

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A method for preparing high-efficiency quantum dot solar cells by growing multilayer quantum dots on chamfered substrates. The chamfered substrate provides enhanced uniformity and control over the quantum dot growth process, while the chamfered surface inhibits dot migration. This approach enables precise control over the quantum dot layer thickness and distribution, leading to improved solar cell performance.

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Zinc sulfide (ZnS) carbon quantum dot solar-blind ultraviolet detector with enhanced photocurrent and responsivity through the use of carbon quantum dots as a carrier transport layer. The detector comprises a ZnS photodetector layer with a carbon quantum dot layer as the carrier transport layer, where the carbon quantum dots facilitate rapid electron-hole separation through their high electron mobility and thermal conductivity. This hybrid layer architecture significantly improves the detector's performance compared to traditional ZnS detectors, enabling higher responsivity and improved detection capabilities in the solar-blind ultraviolet region.

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Quantum dot heterojunction solar cells with enhanced photoelectric conversion efficiency through the integration of quantum dots with multiferroic/ferroelectric layers. The heterojunction structure combines a quantum dot light-absorbing layer with a multiferroic/ferroelectric layer, enabling efficient charge separation and carrier transport. This architecture addresses the limitations of conventional solar cells by addressing carrier diffusion limitations and enhancing photocurrent generation. The multiferroic/ferroelectric layer provides improved electron transmission and charge transport properties, while the quantum dot layer enhances light absorption. The heterojunction architecture enables high-efficiency solar cells with improved water-splitting capabilities.

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All-solid-state solar cells based on simultaneous deposition of quantum dots and a novel preparation method achieve high efficiency, low cost, and stability through a novel device architecture. The solar cells employ quantum dots as light-absorbing materials, which are deposited simultaneously with the photovoltaic layer through a novel deposition process. This approach eliminates the need for organic solvents and high-temperature processing, while maintaining the quantum dot's inherent properties. The device architecture enables efficient charge carrier collection and transport, resulting in improved photovoltaic performance compared to conventional quantum dot solar cells.

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A light-absorbing layer for solar cells that enables efficient two-stage light absorption through a novel intermediate band structure. The layer comprises a bulk semiconductor with a bandgap energy of 2.0 eV or more and 3.0 eV or less, combined with quantum dots that are dispersed in a matrix of the semiconductor. The quantum dots contain a halogen element ligand, which enables efficient absorption of light in the 500 nm to 900 nm range through a two-step process. The layer's intermediate band structure facilitates further absorption of light in the 600 nm to 900 nm range, leading to improved quantum yield and enhanced solar conversion efficiency.

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Quantum dot ink manufacturing method for solar cells that achieves high efficiency and uniformity through a simplified process. The method involves preparing a two-component solution containing quantum dots capped with a ligand and an inorganic compound, followed by a phase-transfer exchange reaction to replace the ligand with a shorter-molecular-weight ligand. The resulting quantum dots are dispersed in a solvent to produce a uniform quantum dot ink. This approach enables the production of high-quality quantum dots with reduced surface defects, improved charge mobility, and enhanced photoelectric conversion efficiency, while maintaining the simplicity of the process compared to conventional ligand exchange methods.

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Semiconductor photoconverters using quantum dots in GaInAs-based heterostructures achieve higher efficiency than traditional cascading structures by leveraging stress-relieved quantum dot absorption. The technology employs InGaAs quantum dots grown on GaAs surfaces with 20-50% indium concentration, providing enhanced absorption beyond the GaInAs bandgap while maintaining current matching with GaInAs-based photovoltaic cells. This approach enables improved spectral sensitivity matching across the GaInAs bandgap, resulting in higher photocurrent densities compared to conventional cascading structures.

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Plasma droplet epitaxial gallium arsenide quantum dot solar cell with improved efficiency through controlled metal nanoparticle deposition. The method employs a mask etching process to create precise metal nanoparticle structures adjacent to quantum dots, enabling precise control over their spatial arrangement. This approach enables the formation of regular and ordered quantum dot structures, which are essential for achieving high efficiency in quantum dot solar cells.

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Solar cells with enhanced spectral response through the use of ZnSe/ZnS colloidal quantum dots. The solar cells incorporate ZnSe/ZnS colloidal quantum dots with negatively charged sulfhydryl groups and positively charged amino groups, which form a core-shell structure. These colloidal quantum dots are prepared through surface electrostatic interaction and are deposited in a layer-by-layer fashion onto a Si-based solar cell surface. The ZnSe/ZnS colloidal quantum dots enable efficient transfer of ultraviolet photons to the solar cell, thereby improving its spectral response beyond the conventional Si-based solar cells.

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