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Solar water splitting using photoelectrochemical cells (PEC's) is a promising pathway toward clean and sustainable storage of renewable energy. Practical realization of solar-driven synthesis of hydrogen and oxygen integrating light absorption and electrolysis of water has been challenging because of (1) the limited stability of good photovoltaic materials under the required electrochemical conditions, and (2) photovoltaic efficiency losses due to light absorption by catalysts, the electrolyte, and generated bubbles, or reflection at their various interfaces. Herein, we evaluate a novel integrated solar water splitting architecture using efficient silicon heterojunction photovoltaic cells that avoids such losses and exhibits a solar-to-hydrogen (STH) efficiency in excess of 10%. Series-connected silicon Heterojunction with Intrinsic Thin layer (HIT) cells generate sufficient photovoltage for unassisted water splitting, with one of the cells acting as the photocathode. Platinum is deposited on the back (dark) junction of this HIT cell as the catalyst for the hydrogen evolution reaction (HER). The photocathode is protected from corrosion by a TiO 2 layer deposited by atomic layer deposition (ALD) interposed between the HIT cell and the Pt, enabling stable operation for >120 hours. Combined with oxygen evolution reaction (OER) catalysts deposited on a porous metal dark anode, these PEC's achieve stable water splitting with a record high STH efficiency for an integrated silicon photosynthesis device.
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This content will become publicly available on November 17, 2025
A MATLAB-Based User Interface to Study the Multi-Reflections and Light Absorption in Textured Solar Cell Surfaces
Improving the efficiency of solar cells is important as it is a sustainable way of energy production with a relatively low power conversion efficiency (PCE). To enhance the efficiency of solar cells, textures can be introduced on the surface which can minimize light ray reflectance, leading to increased light absorption and improvement in overall efficiency. Introduction of texture can also improve the hydrophobicity of the surface which can enhance the self-cleaning capability of solar panels. In this study, a MATLAB-based user interface is developed to facilitate assessing the sunlight absorption in silicon-based solar cells having top layer as a microtextured surface. The user interface employs a multi-faceted mesh-grid algorithm to design 3D textural surface geometries. Core to the program’s functionality is advanced ray tracing simulations that identify points of light intersection on these textures and determine the trajectory of light upon reflection. A notable feature of this user interface is its capability to simulate and analyze the complex phenomenon of multi-reflection in the structure. This iterative process allows for a comprehensive understanding of light interactions in textured surfaces, to find the best structure for maximum absorption. This user-interface provides clarity and ease of use in modeling and analyzing light absorption in textured solar cell surfaces. The modeling framework is validated using experimental observation, and the impact of six 3D surface textures on sunlight absorption of silicon solar cell is studied using the simulation framework. According to the simulation findings, the cavity texture provides more consistent light absorption compared to its protrusion counterpart. Furthermore, hemispherical cavities exhibit consistently high absorption across various incident angles. The results provide useful insights for improving light absorption in the solar cell.
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- Award ID(s):
- 2206864
- PAR ID:
- 10610346
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- ISBN:
- 978-0-7918-8864-3
- Format(s):
- Medium: X
- Location:
- Portland, Oregon, USA
- Sponsoring Org:
- National Science Foundation
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