Bismuth-based oxyhalides have attracted considerable research interest for visible-light-responsive oxygen evolution reaction, however, their ineffective light absorption and charge separation efficiencies remain a challenge. Herein, a novel visible-light-responsive 2D Bi₂SmO₄Cl nanosheet photocatalyst was designed by introducing rare-earth element Sm into BiOCl and thus its electronic structure microenvironment is commendably tailored to promote the light absorption and charge separation. Moreover, iodine doping and IrO₂ cocatalyst are employed to give rise to IrO₂-Bi₂SmO₄Cl_1-xI_x with a remarkable O₂-evolving rate of 151.2 μmol·h⁻¹ under visible light irradiation, which is more than 500-fold of pristine BiOCl. Both the Sm introduction and I doping significantly shorten the band gap and increase the charge separation efficiency. The density functional theory (DFT) calculation demonstrated that Sm can give electrons to other atoms, benefits the charge separation process and decreases the work function of oxygen evolution reaction. This work can offer new insights into the design and structure modulation of bismuth-based oxyhalides.

中文翻译：

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微环境 通过稀土元素钐掺杂调节氯氧化铋的电子结构，实现显著的可见光响应氧析出


铋基卤氧化物在可见光响应析氧反应中引起了相当大的研究兴趣，然而，其无效的光吸收和电荷分离效率仍然是一个挑战。本文通过将稀土元素 Sm 引入 BiOCl 中，设计了一种新型可见光响应式 2D Bi₂SmO₄Cl 纳米片光催化剂，因此其电子结构微环境被定制以促进光吸收和电荷分离。此外，碘掺杂和 IrO₂ 助催化剂在可见光照射下产生 IrO_{2-Bi 2}SmO₄Cl_1-xI_x，其 O₂ 析出速率高达 151.2 μmol·^h-1，是原始 BiOCl 的 500 倍以上。Sm 引入和 I 掺杂都显著缩短了带隙并提高了电荷分离效率。密度泛函理论 （DFT） 计算表明，Sm 可以给其他原子带来电子，有利于电荷分离过程，并降低析氧反应的功函数。这项工作可以为铋基卤氧化物的设计和结构调控提供新的见解。