An array of SnO₂ nanohelix structures is employed to fabricate a SnO₂ helix@ZnFe₂O₄ dendrite core-shell 3D heterostructure photoanode for photoelectrochemical (PEC) water splitting. The SnO₂ helix provides triple critical functions to enhance the PEC performance of the photoanode. First, it scatters the incident light to achieve a higher light harvesting efficiency. Second, it provides a facile electron pathway as an electron transfer layer (ETL) while blocking hole transport to mitigate charge recombination in the bulk of ZnFe₂O₄. Finally, it becomes a template for the formation of ZnFe₂O₄ dendrite nanostructure shell. The ZnFe₂O₄ dendrite/SnO₂ helix photoanode exhibits a remarkable increase in incident photon-to-electron conversion efficiency compared to unmodified ZnFe₂O₄ with no ETL and modified one with "flat" SnO₂ ETL. The surface of the ZnFe₂O₄/SnO₂ helix photoanode is further modified with TiO₂ passivation layer and NiFeO_x oxygen evolution co-catalyst to achieve one of the best PEC performances among reported ZnFe₂O₄-based photoanodes.

中文翻译：

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用于增强光电化学水分解的 ZnFe2O4 枝晶/SnO2 螺旋 3D 异质结构光阳极：SnO2 纳米螺旋的三重功能

采用一系列 SnO ₂纳米螺旋结构来制造用于光电化学 (PEC) 水分解的 SnO ₂螺旋@ZnFe ₂ O ₄枝晶核壳 3D 异质结构光阳极。SnO ₂螺旋提供三重关键功能以增强光电阳极的PEC性能。首先，它散射入射光以实现更高的光收集效率。其次，它提供了一个简单的电子路径作为电子传输层 (ETL)，同时阻止空穴传输以减轻 ZnFe ₂ O ₄主体中的电荷复合。最后，它成为形成 ZnFe ₂ O ₄的模板枝晶纳米结构壳。与没有ETL的未改性ZnFe ₂ O ₄和具有“平坦”SnO ₂ ETL的改性ZnFe ₂ O ₄相比，ZnFe ₂ O ₄枝晶/SnO ₂螺旋光阳极表现出入射光子到电子转换效率的显着提高。ZnFe ₂ O ₄ /SnO ₂螺旋光阳极的表面用TiO ₂钝化层和NiFeO _x析氧助催化剂进一步改性，以实现已报道的基于ZnFe ₂ O ₄的光阳极中最好的PEC性能之一。