Surface Passivation Methods for 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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Solar cell design with improved passivation to enhance photoelectric conversion efficiency. The solar cell has a unique passivation layer structure with higher atomic packing density and thinner average thickness on the surface closest to the substrate compared to the outer passivation layer. This inner passivation layer is formed using atomic layer deposition (ALD) for better coverage and lower defect density compared to plasma enhanced chemical vapor deposition (PECVD). The outer passivation layer is formed using PECVD for faster deposition. The inner ALD passivation layer provides initial surface passivation, followed by the thicker PECVD layer for additional passivation and coverage.

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A solar cell with improved absorption efficiency and reduced stress resistance through optimized passivation layer design. The design incorporates a specific sequence of passivation layers with different refractive indices, where the second layer has a higher refractive index than the third layer. This arrangement enables selective absorption of light across the solar spectrum while minimizing internal reflection and field passivation effects. The second layer, comprising silicon nitride with a specific atomic ratio, provides enhanced absorption properties, while the third layer, comprising silicon oxynitride, enhances the refractive index of the solar cell. The sequence of layers is carefully controlled to balance absorption efficiency with structural integrity and cost considerations.

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A two-step passivation method for solid state quantum devices like quantum dot lasers that improves their optical quality and longevity by effectively removing surface states. The method involves depositing a sulfide layer followed by an oxide layer. First, the devices are pretreated in acid to remove native oxide. Then, they are placed in a hydrogen sulfide-filled chamber with ultraviolet light to displace oxide with sulfur atoms. This forms a compact sulfide layer. Next, the devices are transferred to an atomic layer deposition chamber to deposit a thin oxide layer on top. This completes the passivation process. The sulfide layer reduces surface states, while the oxide isolates the device from air to prevent oxidation.

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Solar cell design with patterned passivation and carrier transmission layers to improve efficiency by reducing interface recombination and allowing efficient charge extraction. The solar cell has light absorption layer with alternating patterned passivation and carrier transmission layers on some of its surfaces. This allows selective passivation of defects at interfaces without blocking charge extraction. The patterned design reduces interface recombination compared to full passivation and improves fill factor and voltage compared to no passivation.

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Surface treatment method for quantum dots that enables reliable and stable quantum dot synthesis through controlled photopolymerization of reactive surface ligands. The method involves supplying quantum dots and reactive ligand solutions through a controlled flow system while irradiating them with a specific light source. The photopolymerization process enables uniform coverage of the quantum dot surface, preventing incomplete coverage and degradation of the quantum dot material.

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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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A solar cell that achieves high open-circuit voltage (VOC) and short-circuit current (JSC) through the integration of quantum dots with different bandgaps in a solution-processed semiconductor matrix. The matrix enables the formation of a composite film with optimized optical absorption properties, specifically tailored to the infrared spectrum. By engineering the density of states in the quantum dots, the matrix achieves improved quasi-Fermi level splitting and increased VOC, while maintaining charge transport properties. This approach enables the realization of solar cells with significantly higher VOC and JSC than conventional Si-based solar cells, approaching the theoretical limit of 6% power conversion efficiency.

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A method for preparing a metal oxide-coated quantum dot and dye co-sensitized solar cell through a single-step process. The method involves converting bulk quantum dots into water-soluble quantum dots through ligand exchange, followed by a hydrothermal reaction to form a thin metal oxide layer on the quantum dots. The resulting quantum dot@metal oxide composite is then coated with a metal oxide layer through annealing, followed by dye deposition. This integrated approach enables the creation of high-efficiency solar cells by combining the benefits of quantum dots as sensitizers with metal oxide electron transport layers.

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Quantum dot particles with enhanced protection against environmental degradation. The particles feature a dual-layer passivation system where the first layer provides moisture barrier protection during deposition, while the second layer offers enhanced surface protection. The first layer is formed prior to deposition and is specifically designed to prevent water contact, while the second layer is deposited on top of the first layer. This dual-layer approach enables effective moisture protection while maintaining sufficient surface coverage for effective quantum dot particle protection.

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Solar cell with enhanced surface passivation through a novel dual-layer approach. The cell features a substrate with two sequential passivation layers: a chemical passivation layer on the surface and a field passivation layer above it. The field passivation layer contains a zwitterionic compound that forms an anionic group at its surface, creating a localized negative charge. This anionic group interacts with the surface defects, reducing carrier recombination and carrier concentration. The chemical passivation layer provides a broader surface coverage, while the field passivation layer enhances the local field effect. The combined dual-layer architecture enables improved surface passivation, leading to enhanced solar cell performance.

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A method for enhancing the efficiency of solar cells by using a layer-by-layer self-assembly ZnSe/ZnS core-shell structure with quantum dots. The method involves depositing ZnSe/ZnS quantum dots with negative surface charge and ZnSe/ZnS quantum dots with positive surface charge through a spin-coating process at low speeds. These core-shell structures are then assembled through layer-by-layer self-assembly to form a fluorescence down transfer layer. The core-shell structure enables efficient transfer of energy from ultraviolet photons to the solar cell's p-n junction, thereby improving spectral response and overall efficiency.

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Preparing a quantum dot-sensitized solar cell with ultra-thin PMMA passivation layer through a novel method that enables both passivation and charge management simultaneously. The process involves depositing a ultra-thin PMMA layer as the passivation interface, which not only prevents interface defects but also suppresses charge recombination. This dual-function approach enables improved charge extraction and collection while maintaining the structural integrity of the passivation layer. The ultra-thin PMMA layer can be deposited using conventional techniques, such as spin coating or evaporation, and is compatible with the quantum dot-sensitized solar cell architecture.

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Quantum dot solar cells with enhanced carrier recombination inhibition through a novel nitride semiconductor layer. The layer, comprising a wide band gap material such as ZnS, Al2O3, or MgO, is deposited on the surface of quantum dots to prevent carrier recombination at the interface. This layer achieves precise control over thickness, allowing precise carrier transport while maintaining optimal contact with the TiO2 surface. The nitride layer enables efficient hole transport while minimizing carrier recombination, resulting in improved solar cell efficiency.

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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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CsPbBr3 quantum dot-silicon composite solar cell that improves efficiency by adding a thin layer of CsPbBr3 quantum dots on the silicon chip. The quantum dots absorb short-wavelength UV light that silicon can't and convert it to visible light that silicon can absorb. This reduces reflection, increases short-circuit current, and external quantum efficiency at short wavelengths. The CsPbBr3 quantum dot film is spin-coated with thickness 20-50nm.

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A method for preparing high-performance quantum dots for solar cells that overcomes the limitations of conventional quantum dot-metal oxide interfaces. The method involves modifying oil-soluble quantum dots with silane coupling agents to create surface-modified quantum dots, followed by a cross-linking reaction with fullerol to form stable nanoparticles. These modified quantum dots exhibit enhanced charge transfer properties compared to conventional interfaces, enabling efficient charge collection in solar cells.

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Preparation of photoanode for co-sensitized quantum dot solar cells through the synthesis of Zn-Cu-In-Se (ZCISe) quantum dots. The synthesis of ZCISe quantum dots involves the controlled synthesis of Zn-Cu-In-Se nanocrystals in water, followed by their subsequent conversion to oil-soluble form. This enables the preparation of water-soluble ZCISe quantum dots that can be used to create co-sensitized photoanodes for quantum dot solar cells. The photoanode is then assembled by combining the ZCISe quantum dots with CdSe quantum dots, resulting in a co-sensitized photoanode that achieves high photocurrent and photoelectric conversion efficiency.

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A method for preparing CdSeTe quantum dot sensitized solar cells with enhanced surface passivation properties. The method involves preparing a Se source solution by magnetic stirring of Se powder in liquid paraffin at 100°C, followed by controlled cooling to form a transparent and colorless solution. The Cd source solution is prepared by stirring CdC12 · 2.5H2O powder in liquid paraffin, with the stirring process controlled to prevent agglomeration. The Se source solution is then used to prepare CdSeTe quantum dots, which are then sensitized with the Se source solution to form sensitized quantum dots. The sensitized quantum dots are then sensitized with the Cd source solution to form sensitized solar cells with improved surface passivation properties.

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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 groups, which form a core-shell structure through surface electrostatic interaction. The ZnSe/ZnS colloidal quantum dots enable efficient conversion of ultraviolet (UV) photons into visible light, significantly improving the solar cell's spectral response beyond the traditional Si-based solar cells.

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Quantum dot sensitized solar cells achieve enhanced photoelectric conversion efficiency through a novel surface modification technique. The method involves depositing a wide band gap semiconductor layer on the surface of quantum dots using atomic layer deposition (ALD), which effectively suppresses recombination of photogenerated electrons and electrolytes. This surface modification layer is fabricated through a precise control of precursor deposition conditions, enabling precise control of the semiconductor layer thickness and composition. The resulting quantum dot sensitized solar cells exhibit improved stability and efficiency compared to conventional methods.

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Solar cell with enhanced UV stability through a novel passivation layer that incorporates multiple phases of silicon oxynitride. The layer, formed on the semiconductor substrate's light incident surface, comprises a silicon oxynitride material with distinct phase compositions. This multi-phase structure provides superior UV protection while maintaining electrical conductivity, enabling the solar cell to maintain its open-circuit voltage even when exposed to continuous UV radiation.

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Preparation of POSS-modified CdTe quantum dot sensitized solar cells through surface modification of CdTe quantum dots with poly(phenylene sulfone) (PPS) nanoparticles. The modification enhances the photoelectric conversion efficiency and stability of CdTe quantum dots by modifying their surface properties, particularly through the incorporation of PPS nanoparticles that form a protective layer on the CdTe surface. This surface modification enables improved electron injection into the TiO2 electrode, thereby enhancing the overall solar cell performance.

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Quantum dot sensitized solar cells with enhanced efficiency through precise control of quantum dot film thickness. The cells employ a nanocrystalline porous substrate with a quantum dot layer that is precisely deposited using an ultrasonic spray method. The thickness of the quantum dot layer is carefully controlled between 2-50 nm, with optimal thicknesses identified through computational modeling. This controlled thickness ensures optimal carrier transmission and recombination properties, while maintaining the necessary quantum yield for multi-exciton conversion. The porous substrate provides a uniform interface between the quantum dots and the electrolyte, enabling efficient charge collection and transport.

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A passivation layer for quantum dot sensitized solar cells that enhances charge transport and reduces recombination. The layer is formed through continuous immersion of the sensitized photoanode film in a MnS solution, with particle diameters below 15 nm. This process creates a uniform MnS layer that not only protects the quantum dots from corrosion but also enables efficient hole transport and electron migration. The MnS layer is deposited on the quantum dot layer surface, allowing it to act as a barrier to recombination while facilitating charge transport. This layer is particularly effective for improving the efficiency of quantum dot sensitized solar cells by reducing electron-hole recombination.

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Passivation of semiconductor nanoparticles using a solution-based approach to achieve high efficiency solar cells. The method involves treating semiconductor quantum dots with a solution containing a cationic reagent that selectively binds to surface anions, followed by treatment with a cation-containing reagent. This process forms a passivated core with cations, which enables the formation of high-efficiency solar cells through the absorption of visible and infrared light. The solution-based approach eliminates the need for organic ligands, enabling nanocrystal-to-nanocrystal passivation and improved carrier mobility.

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Quantum dot solar cells with enhanced efficiency through a novel interface modification. The solar cells incorporate a self-assembled monolayer (SAM) layer at the interface between the quantum dot layer and a metal oxide layer, which contains a benzene ring with pi-pi interaction. This SAM layer protects the quantum dots from ligand exchange damage during the deposition process, leading to improved photovoltaic performance. The solar cells achieve a power conversion efficiency of 10.7% and demonstrate enhanced current density, voltage, and charging efficiency compared to conventional quantum dot solar cells.

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A method to enhance the surface passivation of solar cells by combining a hydrogen ion passivation process with a diffusion step. The process involves applying a hydrogen ion passivation treatment between the cleaning and etching steps, followed by diffusion. This integrated approach addresses both hydrogen ion contamination and dangling bonds, resulting in improved solar cell performance.

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A CdII-MnxSe quantum dot solar cell preparation method that enhances solar cell efficiency through precise control of wide bandgap semiconductor materials. The method employs a controlled chemical bath deposition process to deposit CdII-MnxSe quantum dots, which are then combined with other semiconductor materials to form the solar cell. The precise deposition conditions allow for optimal quantum dot size and distribution, while maintaining the semiconductor material's intrinsic properties. This approach enables the creation of high-efficiency solar cells with improved optical and electrical performance.

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Composition for a quantum dot capping ligand comprising a dithiol compound, a dithiol-capped quantum dot, and a solar cell using the same. The composition includes a dithiol compound, a dithiol-capped quantum dot, and a solar cell using the same.

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A method for preparing a tunable composite quantum dot-sensitized photoelectric electrode for solar cells, enabling broad spectral response and efficient charge transport. The method employs a SILAR process that sequentially adsorbs and reacts CdS precursors with methanol solution, followed by Zn2+ source precursor solution. The resulting composite material exhibits a wide spectral response, with the Zn2+ source precursor selectively promoting surface passivation of CdS surface defects, thereby suppressing carrier recombination.

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A colloidal quantum dot-sensitized solar cell substrate with improved conversion efficiency through precise control of quantum dot size and distribution. The substrate incorporates colloidal quantum dots with controlled particle sizes and closely packed structures, enabling efficient light absorption and charge carrier collection. The precise control of quantum dot size and distribution enables optimal absorption and charge transport properties, resulting in higher conversion efficiency compared to conventional colloidal quantum dot solar cells.

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Environmental-friendly quantum dot solar cell that achieves high efficiency through a novel CuInS2/ZnS core-shell quantum dot structure. The solar cell employs CuInS2/ZnS core-shell quantum dots as the active layer, with the ZnS shell providing enhanced stability and durability. The ZnS shell wraps around the CuInS2 core, forming a stable and efficient material system that maintains the solar cell's performance characteristics while eliminating the need for heavy metals. The manufacturing process involves a simple and environmentally friendly method of preparing the ZnS shell-coated CuInS2/ZnS quantum dots. This approach enables the production of high-efficiency solar cells with reduced environmental impact.

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Rare-earth selenide quantum dot solar cells that achieve high photoelectric conversion efficiency through controlled synthesis and assembly of rare-earth selenide quantum dots. The synthesis process involves solvothermal synthesis of rare-earth selenide quantum dots in both organic and aqueous phases, followed by assembly with titanium dioxide to form a solar cell. The solvothermal synthesis enables precise control over the size and distribution of the quantum dots, while the assembly process enables efficient integration with the titanium dioxide matrix.

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A heterojunction solar cell that achieves improved passivation through a novel surface passivation method. The method involves forming an intrinsic layer on the wafer surface before screen printing the photovoltaic layer, followed by doping the intrinsic layer with a p-type material. The intrinsic layer is then annealed to fully diffuse hydrogen atoms and reduce defect states, while the p-type layer is deposited on the annealed intrinsic layer. This approach ensures the intrinsic layer remains fully annealed during doping, enhancing passivation and preventing boron diffusion into the p-type layer.

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A nano-crystal/silicon solar cell that combines the high absorption efficiency of quantum dots with the efficiency of crystalline silicon. The solar cell incorporates quantum dots that modulate the silicon absorption spectrum, reducing reflections and increasing photocurrent density. The quantum dots enhance the silicon absorption edge, while the silicon substrate provides the base for the photovoltaic action. This hybrid approach enables significant improvements in conversion efficiency beyond traditional silicon-based solar cells.

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A photovoltaic cell with improved power conversion efficiency through enhanced quantum dot performance. The cell incorporates a light-absorbing layer with quantum dots that undergo controlled defect repair through repeated salt treatment and ligand replacement cycles. This process enables the formation of high-quality quantum dots with reduced mobility issues, resulting in improved photovoltaic performance. The cell architecture includes a transparent semiconductor substrate, a light-absorbing layer with quantum dots, and an interfacial layer. The salt treatment and ligand replacement steps are repeated multiple times to achieve the desired quantum dot quality.

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A method for preparing quantum dot-decorated metal oxide solar cells that enhances their photoelectric conversion efficiency. The method involves growing quantum dots on the surface of metal oxide anode materials through chemical interaction, followed by deposition of the quantum dot-decorated metal oxide onto the solar cell surface. This approach enables direct growth of quantum dots on the metal oxide surface, bypassing the conventional synthesis of quantum dots and metal oxide layers. The quantum dot-decorated metal oxide surface exhibits improved carrier transmission properties, leading to enhanced solar cell efficiency.

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