Here presented are the properties and performance of a new metallo‐dielectric waveguide array structure as the encapsulation material for silicon solar cells. The arrays are produced through light‐induced self‐writing combined with in situ photochemical synthesis of silver nanoparticles. Each waveguide comprises a cylindrical core consisting of a high refractive index polymer and silver nanoparticles homogenously dispersed in its medium, all of which are surrounded by a low refractive index common cladding. The waveguide array‐based films are processed directly over a silicon solar cell. Arrays with systematically varied concentration of AgSbF6 as the salt precursor are explored. The structures are tested for their wide‐angle light capture capabilities, specifically toward enhanced conversion efficiency and current production of encapsulated solar cells. Observed are increases in the external quantum efficiency, especially at wide incident angles up to 70°, and nominal increases in the short circuit current density by 1 mA cm−2 (relative to an array without nanoparticles). Enhanced light collection is explained in terms of the beneficial effect of scattering by the nanoparticles along the waveguide cores. This is a promising approach toward solar cell encapsulants that aid to increase solar cell output over both the course of the day and year.
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Microfiber Optic Arrays as Top Coatings for Front-Contact Solar Cells toward Mitigation of Shading Loss
Microfiber optic array structures are fabricated and employed as an optical structure overlaying a front-contact silicon solar cell. The arrays are synthesized through light-induced self-writing in a photo-crosslinking acrylate resin, which produces periodically spaced, high-aspect-ratio, and vertically aligned tapered microfibers deposited on a transparent substrate. The structure is then positioned over and sealed onto the solar cell surface. Their fiber optic properties enable collection of non-normal incident light, allowing the structure to mitigate shading loss through the redirection of incident light away from contacts and toward the solar cell. Angle-averaged external quantum efficiency increases nominally by 1.61%, resulting in increases in short-circuit current density up to 1.13 mA/cm2. This work demonstrates a new approach to enhance light collection and conversion using a scalable, straightforward, light-based additive manufacturing process.
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- NSF-PAR ID:
- 10158860
- Date Published:
- Journal Name:
- ACS applied materials interfaces
- Volume:
- 11
- Issue:
- 50
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 47422–47427
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Here presented are the properties and performance of a new metallo‐dielectric waveguide array structure as the encapsulation material for silicon solar cells. The arrays are produced through light‐induced self‐writing combined with in situ photochemical synthesis of silver nanoparticles. Each waveguide comprises a cylindrical core consisting of a high refractive index polymer and silver nanoparticles homogenously dispersed in its medium, all of which are surrounded by a low refractive index common cladding. The waveguide array‐based films are processed directly over a silicon solar cell. Arrays with systematically varied concentration of AgSbF6as the salt precursor are explored. The structures are tested for their wide‐angle light capture capabilities, specifically toward enhanced conversion efficiency and current production of encapsulated solar cells. Observed are increases in the external quantum efficiency, especially at wide incident angles up to 70°, and nominal increases in the short circuit current density by 1 mA cm−2(relative to an array without nanoparticles). Enhanced light collection is explained in terms of the beneficial effect of scattering by the nanoparticles along the waveguide cores. This is a promising approach toward solar cell encapsulants that aid to increase solar cell output over both the course of the day and year.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/acsami.9b17803
