It is highly desirable to develop new semiconductors for the photocatalytic reduction of CO₂ to CH₄ and CO to solve greenhouse effect and energy issues. Defect pyrochlore oxides have a flexible composition and the electron/hole mobility can be manipulated by introducing foreign cations into the structure. Through Sn doping into the defect pyrochlore oxide KNbWO₆·H₂O, we successfully obtained a 2-times higher photocatalytic activity for converting CO₂ to CO, CH₄ and O₂ compared to the original KNbWO₆·H₂O. According to the data from UV-vis, photoluminescence, and hydroxyl radical amount-related fluorescence spectra, and CO₂ adsorption, the improved photocatalytic activity can be attributed to the extended visible light response, the enhanced charge separation and the improved CO₂ adsorption due to Sn doping. Our results provide a new strategy for developing high-performance photocatalysts.

中文翻译：

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掺锡缺陷的烧绿石氧化物KNbWO ₆ ·H ₂ O微晶及其对CO ₂ †的光催化还原

迫切需要开发用于将CO ₂光催化还原为CH ₄和CO的新半导体，以解决温室效应和能源问题。缺陷的烧绿石氧化物具有柔性的组成，可以通过将外来阳离子引入结构来控制电子/空穴迁移率。至Sn掺杂到缺陷烧绿石氧化物KNbWO ₆ ·H ₂ O，我们成功地获得了更高的2倍的光催化活性，用于将CO ₂以CO，CH ₄和O ₂相比于原始KNbWO ₆ ·H ₂O.根据来自紫外可见光，光致发光和与羟基自由基相关的荧光光谱以及CO ₂吸附的数据，光催化活性的提高可归因于可见光响应的扩展，电荷分离的增强和CO ₂的提高锡掺杂引起的吸附。我们的结果为开发高性能光催化剂提供了新的策略。