Photoelectrochemical (PEC) water splitting provides a potential method to produce renewable hydrogen energy, but there is still plenty of room for improving the efficiency and stability of photoelectrodes. In this paper, we present a metal–insulator-semiconductor (MIS) structure based on p-Si that enables stable and efficient water splitting by engineering the interfacial insulating layer. The silicon oxide (SiO) film with appropriate thickness and low defects is regrown by a chemical oxidation process, which provides a high-quality insulating layer to passivate the p-Si. The carrier flux, barrier height and interfacial resistance of p-Si based MIS junction can be systematically tuned by controlling the thickness and quality of SiO layer. Under AM 1.5G illumination, the optimized p-Si/SiO/Ti/Pt photoelectrode shows an onset potential of 0.5 V RHE, a maximum photocurrent of 28 mA/cm and a high applied bias photon-to-current efficiency (ABPE) of 6 %. These results have significant implications for constructing MIS photoelectrodes towards effective water splitting.

中文翻译：

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设计用于光电化学制氢的硅基金属-绝缘体-半导体结的 SiOx 界面层


光电化学（PEC）水分解提供了一种生产可再生氢能的潜在方法，但光电极的效率和稳定性仍有很大的提高空间。在本文中，我们提出了一种基于 p-Si 的金属-绝缘体-半导体 (MIS) 结构，该结构通过设计界面绝缘层来实现稳定、高效的水分解。通过化学氧化工艺重新生长具有适当厚度和低缺陷的氧化硅（SiO）薄膜，这提供了高质量的绝缘层来钝化p-Si。 p-Si基MIS结的载流子通量、势垒高度和界面电阻可以通过控制SiO层的厚度和质量来系统地调节。在 AM 1.5G 照明下，优化的 p-Si/SiO/Ti/Pt 光电极表现出 0.5 V RHE 的起始电位、28 mA/cm 的最大光电流和6%。这些结果对于构建 MIS 光电极以实现有效的水分解具有重要意义。