Abstract Hydrogen gas produced from a photovoltaic power source for water electrolysis is a promising renewable, low-cost, storable, and transportable energy source. Herein, we propose a simply integrated hydrogenated amorphous silicon germanium (a-SiGe:H)/silicon heterojunction (SHJ) tandem configuration as an integrated photovoltaic-electrolysis device. By optimising the a-SiGe:H top cell for high efficiency using various band-gap engineering techniques, we achieve effective performance enhancement, with a maximum Voc of greater than 1.5 V. Assuming an ideal condition wherein the photovoltaic device operates at maximum power and the output conversion performance is maximized, we estimate a solar-to-hydrogen (STH) conversion performance of 13.1%. The integrated a-SiGe:H/SHJ structure can generate a sufficiently high voltage for water electrolysis while using lesser silicon than single-junction silicon solar cells connected in series. Consequently, it is a viable option for a low-cost, high-efficiency integrated photovoltaic-electrolysis system and an alternative to traditional hydrogen production from fossil fuels.

中文翻译：

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用于太阳能到氢气转换的基于单晶硅的串联配置

摘要 由光伏电源产生的用于水电解的氢气是一种很有前途的可再生、低成本、可储存和可运输的能源。在此，我们提出了一种简单集成的氢化非晶硅锗 (a-SiGe:H)/硅异质结 (SHJ) 串联配置作为集成光伏电解装置。通过使用各种带隙工程技术优化 a-SiGe:H 顶部电池以获得高效率，我们实现了有效的性能提升，最大 Voc 大于 1.5 V。假设理想条件下光伏器件以最大功率运行，并且输出转换性能最大化，我们估计太阳能到氢 (STH) 的转换性能为 13.1%。集成 a-SiGe：H/SHJ 结构可以产生足够高的电压用于水电解，同时使用比串联的单结硅太阳能电池更少的硅。因此，它是低成本、高效率集成光伏电解系统的可行选择，也是传统化石燃料制氢的替代方案。