In this work, a type-II heterojunction was constructed between g-C₃N₄ and BiOI by ultrasonically assisted hydrothermal synthesis for photoelectrochemical water splitting. The g-C₃N₄ was decorated on BiOI microspheres with a well-defined heterostructure, which reduced the charge recombination process, consistent with the data from photoluminescence (PL) and electrochemical impedance spectroscopy (EIS). The g-C₃N₄/BiOI hybrid material exhibits enhanced photocurrent density, ∼13-fold higher than that of g-C₃N₄ and ∼2 fold higher than pristine BiOI. Furthermore, high stability was achieved for the g-C₃N₄/BiOI hybrid material with 6 wt% g-C₃N₄ for up to 6000 s at 1.23 V vs. RHE, and the photo-conversion efficiency reached 14-fold higher than that of g-C₃N₄ and 1.6 times higher than that of BiOI microspheres. The high photoelectrocatalytic performance achieved by the 6% g-C₃N₄/BiOI material was attributed to the formation of type-II heterojunction between the g-C₃N₄ and BiOI interfaces that could facilitate the photoinduced charge separation–migration and thereby minimize the charge recombination process.

中文翻译：

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通过在g-C3N4和BiOI之间构建II型​​异质结来调节光电化学水分解性能

在这项工作中，通过超声辅助水热合成进行光电化学水分解，在gC ₃ N ₄和BiOI之间构建了II型异质结。gC ₃ N ₄在具有明确定义的异质结构的BiOI微球上进行修饰，这减少了电荷重组过程，与来自光致发光（PL）和电化学阻抗谱（EIS）的数据一致。gC ₃ N ₄ / BiOI杂化材料显示出增强的光电流密度，比gC ₃ N ₄高约13倍，比原始BiOI高约2倍。此外，gC ₃ N的稳定性高具有6 wt％gC ₃ N _4的4 / BiOI杂化材料在1.23 V相对于RHE的作用下长达6000 s，光转换效率比gC ₃ N ₄高14倍，比gC ₃ N ₄高1.6倍BiOI微球。6％gC ₃ N ₄ / BiOI材料实现的高光电催化性能归因于gC ₃ N ₄和BiOI界面之间形成的II型异质结，可以促进光致电荷的分离和迁移，从而使电荷重组最小化处理。