The Experts below are selected from a list of 49785 Experts worldwide ranked by ideXlab platform
Jeffrey A Hubbell - One of the best experts on this subject based on the ideXlab platform.
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characterization of permeability and network structure of interfacially photopolymerized poly ethylene glycol diacrylate hydrogels
Biomaterials, 1998Co-Authors: Gregory M Cruise, David S Scharp, Jeffrey A HubbellAbstract:Hydrogel membranes formed by interfacially photopolymerizing poly(ethylene glycol) (PEG) diacrylate Precursor Solution were prepared from PEG diacrylate of molecular weights (MW) ranging from 2000 (2K) to 20000 (20K) with concentrations ranging from 10% to 30% w/w. The effects of PEG diacrylate MW and concentration in the membrane Precursor Solution upon the diffusivities of vitamin B12, myoglobin, ovalbumin, albumin, and IgG were determined. Regardless of the concentration of the PEG diacrylate in the Precursor Solution, hydrogels prepared with PEG 2K, 4K, and 8K diacrylate were impermeable to proteins with a size equal to or larger than myoglobin (22 kDa), while hydrogels prepared with PEG 20K diacrylate were impermeable to proteins with a size equal to or larger than ovalbumin (45 kDa). Similarities between hydrogels formed from PEG 2K, 4K, and 8K diacrylates were also seen in calculations of the molecular weight between crosslinks and the mesh size, with values in the range of 150-750 g/mol and 15-35 A, respectively, depending on PEG diacrylate concentration. In contrast, hydrogels formed from PEG 20K diacrylate had molecular weight between crosslinks ranging from 1150 to 2000 g/mol and mesh sizes ranging from 45-70 A, with larger values being observed in membranes polymerized from more dilute PEG diacrylate Precursor. [on SciFinder (R)]
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characterization of permeability and network structure of interfacially photopolymerized poly ethylene glycol diacrylate hydrogels
Biomaterials, 1998Co-Authors: Gregory M Cruise, David S Scharp, Jeffrey A HubbellAbstract:Hydrogel membranes formed by interfacially photopolymerizing poly(ethylene glycol) (PEG) diacrylate Precursor Solution were prepared from PEG diacrylate of molecular weights (MW) ranging from 2000 (2K) to 20000 (20K) with concentrations ranging from 10% to 30% w/w. The effects of PEG diacrylate MW and concentration in the membrane Precursor Solution upon the diffusivities of vitamin B12, myoglobin, ovalbumin, albumin, and IgG were determined. Regardless of the concentration of the PEG diacrylate in the Precursor Solution, hydrogels prepared with PEG 2K, 4K, and 8K diacrylate were impermeable to proteins with a size equal to or larger than myoglobin (22 kDa), while hydrogels prepared with PEG 20K diacrylate were impermeable to proteins with a size equal to or larger than ovalbumin (45 kDa). Similarities between hydrogels formed from PEG 2K, 4K, and 8K diacrylates were also seen in calculations of the molecular weight between crosslinks and the mesh size, with values in the range of 150-750 g/mol and 15-35 A, respectively, depending on PEG diacrylate concentration. In contrast, hydrogels formed from PEG 20K diacrylate had molecular weight between crosslinks ranging from 1150 to 2000 g/mol and mesh sizes ranging from 45-70 A, with larger values being observed in membranes polymerized from more dilute PEG diacrylate Precursor.
Gregory M Cruise - One of the best experts on this subject based on the ideXlab platform.
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characterization of permeability and network structure of interfacially photopolymerized poly ethylene glycol diacrylate hydrogels
Biomaterials, 1998Co-Authors: Gregory M Cruise, David S Scharp, Jeffrey A HubbellAbstract:Hydrogel membranes formed by interfacially photopolymerizing poly(ethylene glycol) (PEG) diacrylate Precursor Solution were prepared from PEG diacrylate of molecular weights (MW) ranging from 2000 (2K) to 20000 (20K) with concentrations ranging from 10% to 30% w/w. The effects of PEG diacrylate MW and concentration in the membrane Precursor Solution upon the diffusivities of vitamin B12, myoglobin, ovalbumin, albumin, and IgG were determined. Regardless of the concentration of the PEG diacrylate in the Precursor Solution, hydrogels prepared with PEG 2K, 4K, and 8K diacrylate were impermeable to proteins with a size equal to or larger than myoglobin (22 kDa), while hydrogels prepared with PEG 20K diacrylate were impermeable to proteins with a size equal to or larger than ovalbumin (45 kDa). Similarities between hydrogels formed from PEG 2K, 4K, and 8K diacrylates were also seen in calculations of the molecular weight between crosslinks and the mesh size, with values in the range of 150-750 g/mol and 15-35 A, respectively, depending on PEG diacrylate concentration. In contrast, hydrogels formed from PEG 20K diacrylate had molecular weight between crosslinks ranging from 1150 to 2000 g/mol and mesh sizes ranging from 45-70 A, with larger values being observed in membranes polymerized from more dilute PEG diacrylate Precursor. [on SciFinder (R)]
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characterization of permeability and network structure of interfacially photopolymerized poly ethylene glycol diacrylate hydrogels
Biomaterials, 1998Co-Authors: Gregory M Cruise, David S Scharp, Jeffrey A HubbellAbstract:Hydrogel membranes formed by interfacially photopolymerizing poly(ethylene glycol) (PEG) diacrylate Precursor Solution were prepared from PEG diacrylate of molecular weights (MW) ranging from 2000 (2K) to 20000 (20K) with concentrations ranging from 10% to 30% w/w. The effects of PEG diacrylate MW and concentration in the membrane Precursor Solution upon the diffusivities of vitamin B12, myoglobin, ovalbumin, albumin, and IgG were determined. Regardless of the concentration of the PEG diacrylate in the Precursor Solution, hydrogels prepared with PEG 2K, 4K, and 8K diacrylate were impermeable to proteins with a size equal to or larger than myoglobin (22 kDa), while hydrogels prepared with PEG 20K diacrylate were impermeable to proteins with a size equal to or larger than ovalbumin (45 kDa). Similarities between hydrogels formed from PEG 2K, 4K, and 8K diacrylates were also seen in calculations of the molecular weight between crosslinks and the mesh size, with values in the range of 150-750 g/mol and 15-35 A, respectively, depending on PEG diacrylate concentration. In contrast, hydrogels formed from PEG 20K diacrylate had molecular weight between crosslinks ranging from 1150 to 2000 g/mol and mesh sizes ranging from 45-70 A, with larger values being observed in membranes polymerized from more dilute PEG diacrylate Precursor.
Hyung Do Kim - One of the best experts on this subject based on the ideXlab platform.
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sn iv free tin perovskite films realized by in situ sn 0 nanoparticle treatment of the Precursor Solution
Nature Communications, 2020Co-Authors: Tomoya Nakamura, Shinya Yakumaru, Minh Anh Truong, Kyusun Kim, Jiewei Liu, Kento Otsuka, Ruito Hashimoto, Richard Murdey, Takahiro Sasamori, Hyung Do KimAbstract:The toxicity of lead perovskite hampers the commercialization of perovskite-based photovoltaics. While tin perovskite is a promising alternative, the facile oxidation of tin(II) to tin(IV) causes a high density of defects, resulting in lower solar cell efficiencies. Here, we show that tin(0) nanoparticles in the Precursor Solution can scavenge tin(IV) impurities, and demonstrate that this treatment leads to effectively tin(IV)-free perovskite films with strong photoluminescence and prolonged decay lifetimes. These nanoparticles are generated by the selective reaction of a dihydropyrazine derivative with the tin(II) fluoride additive already present in the Precursor Solution. Using this nanoparticle treatment, the power conversion efficiency of tin-based solar cells reaches 11.5%, with an open-circuit voltage of 0.76 V. Our nanoparticle treatment is a simple and broadly effective method that improves the purity and electrical performance of tin perovskite films. Tin based perovskites are easily oxidized, which generates large density of defects and compromised the solar cell efficiency. Here Nakamura et al. add metallic tin nanoparticles in the Precursor Solution to suppress tin (IV) impurities and enable high efficiency tin based perovskite solar cells.
Daocheng Pan - One of the best experts on this subject based on the ideXlab platform.
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a general water based Precursor Solution approach to deposit earth abundant cu2znsn s se 4 thin film solar cells
Journal of Power Sources, 2016Co-Authors: Yanchun Yang, Xiaojiao Kang, Lijian Huang, Song Wei, Daocheng PanAbstract:Abstract Earth abundant Cu 2 ZnSn(S,Se) 4 (CZTSSe) has been considered as one of the most promising thin film solar cell absorber candidates. Here, we develop a facile water-based Precursor Solution approach for depositing high-efficiency Cu 2 ZnSn(S,Se) 4 thin film solar cells. In this environmentally friendly approach, inexpensive elemental Cu, Zn, Sn and S powders are used as the starting materials and are dissolved in the aqueous Solution of thioglycolic acid and methylamine, forming a homogeneous Precursor Solution for depositing Cu 2 ZnSnS 4 nanocrystal thin film. As-deposited CZTS nanocrystal thin films are selenized to form the large-grain CZTSSe absorber layers. It was found that Na doping plays an important role in the formation of the extremely dense and flat CZTSSe absorber layer, and fill factor can be significantly improved for Na-doped CZTSSe solar cells, which lead to a photoelectric conversion efficiency of 6.96% with an open-circuit voltage of 378 mV, a short current density of 28.17 mA cm −2 , and a fill factor of 65.4%.
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a robust and low cost strategy to prepare cu2znsns4 Precursor Solution and its application in cu2znsn s se 4 solar cells
RSC Advances, 2015Co-Authors: Qingwen Tian, Yong Cui, Gang Wang, Daocheng PanAbstract:The metal chalcogenides are excellent choices as absorbers and buffer-layers in thin film solar cells. Versatile chemical approaches provide endless possibilities to prepare metal sulfide Precursor Solutions. Recently, Cu2ZnSnS(Se)4 thin films have played an important role in fabricating low-cost and high-efficiency solar cells. Here, we present a robust and low-cost 1,2-ethanedithiol/ethanolamine/2-methoxyethanol ternary Solution process to prepare Cu2ZnSnS4 Precursor Solution and high-quality Cu2ZnSnS4 thin films. Low-cost Cu2O, ZnO and SnO are used as the raw materials, which can be easily dissolved in the 2-methoxyethanol Solution of 1,2-ethanedithiol and ethanolamine at room temperature in air. By tuning the composition of the Cu2ZnSn(S,Se)4 thin film with a selenization process, an active-area power conversion efficiency of 7.34% has been achieved for Cu2ZnSn(S,Se)4 solar cell.
Tomoya Nakamura - One of the best experts on this subject based on the ideXlab platform.
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sn iv free tin perovskite films realized by in situ sn 0 nanoparticle treatment of the Precursor Solution
Nature Communications, 2020Co-Authors: Tomoya Nakamura, Shinya Yakumaru, Minh Anh Truong, Kyusun Kim, Jiewei Liu, Kento Otsuka, Ruito Hashimoto, Richard Murdey, Takahiro Sasamori, Hyung Do KimAbstract:The toxicity of lead perovskite hampers the commercialization of perovskite-based photovoltaics. While tin perovskite is a promising alternative, the facile oxidation of tin(II) to tin(IV) causes a high density of defects, resulting in lower solar cell efficiencies. Here, we show that tin(0) nanoparticles in the Precursor Solution can scavenge tin(IV) impurities, and demonstrate that this treatment leads to effectively tin(IV)-free perovskite films with strong photoluminescence and prolonged decay lifetimes. These nanoparticles are generated by the selective reaction of a dihydropyrazine derivative with the tin(II) fluoride additive already present in the Precursor Solution. Using this nanoparticle treatment, the power conversion efficiency of tin-based solar cells reaches 11.5%, with an open-circuit voltage of 0.76 V. Our nanoparticle treatment is a simple and broadly effective method that improves the purity and electrical performance of tin perovskite films. Tin based perovskites are easily oxidized, which generates large density of defects and compromised the solar cell efficiency. Here Nakamura et al. add metallic tin nanoparticles in the Precursor Solution to suppress tin (IV) impurities and enable high efficiency tin based perovskite solar cells.