Abstract Achieving stable operation of photoanodes used as components of solar water splitting devices is critical to realizing the promise of this renewable energy technology. In this work, amorphous carbon films (a-C), NiCo2O4 (NCO) and NCO/a-C bilayer films as protective layers were prepared on the surface of silicon, respectively. By comparing these protective layers of Si photoanode, we find that the NCO film can effectively protect Si from corrosion. It can not only lower initial potential but also increase photocurrent density. The NCO films were found to have the best catalytic performance. The photocurrent density of the NCO (60 nm)/Si photoanode is 185.6 mA/cm2 and that of the NCO (60 nm)/a-C (14 nm)/Si photoanode reaches high to 586.4 mA/cm2 at a voltage of 6 V vs SCE. The carbon interlayer reduces the width of depletion region built with n-Si, which further improves the current density of the NCO/Si photoanode. The photocurrent density of the NCO/a-C/Si photoanode is more than three times higher than that of the NCO/Si photoanode. The NCO/a-C bilayer film is an ideal protective layer of Si photoanode for photochemical water decomposition.

中文翻译：

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显着提高用于水分解的 NiCo2O4/aC/Si 光阳极中的光电流密度

摘要 实现用作太阳能水分解装置组件的光阳极的稳定运行对于实现这种可再生能源技术的前景至关重要。在这项工作中，分别在硅表面制备了无定形碳膜（aC）、NiCo2O4（NCO）和 NCO/aC 双层膜作为保护层。通过比较硅光阳极的这些保护层，我们发现 NCO 膜可以有效地保护硅免受腐蚀。它不仅可以降低初始电位，还可以增加光电流密度。发现 NCO 薄膜具有最好的催化性能。NCO (60 nm)/Si 光阳极的光电流密度为 185.6 mA/cm2，而 NCO (60 nm)/aC (14 nm)/Si 光阳极的光电流密度在 6 V vs分会。碳夹层减少了用 n-Si 构建的耗尽区的宽度，这进一步提高了 NCO/Si 光阳极的电流密度。NCO/aC/Si 光阳极的光电流密度是 NCO/Si 光阳极的三倍以上。NCO/aC双层膜是用于光化学水分解的Si光阳极的理想保护层。