Strategies for effectively enhancing the photoreduction of CO₂ have been studied for several decades. In this work, Zn₂GeO₄/Mg-MOF-74 composites were prepared via a hydrothermal method. The X-ray diffraction (XRD) patterns, scanning electron microscopy (SEM) images and transmission electron microscopy (TEM) images demonstrate the successful synthesis of Zn₂GeO₄/Mg-MOF-74 composites. The infrared spectra and TEM images indicate a close interaction between Zn₂GeO₄ and Mg-MOF-74, which is attributed to tetramethylammonium hydroxide (TMAOH) adsorbed on Zn₂GeO₄ and interacts with 2,5-dioxide-1,4-benzenedicarboxylate (H₄DOBDC) from Mg-MOF-74. The CO₂ adsorption isotherms illustrate that the incorporation of Mg-MOF-74 into Zn₂GeO₄ nanorods improved the adsorption of CO₂. Only with water as the sacrificial agent, the hydrothermally prepared Zn₂GeO₄/Mg-MOF-74 catalyst exhibited a superior performance for the conversion of CO₂ into carbon monoxide compared to that of single Zn₂GeO₄ or a physical mixture of Zn₂GeO₄/Mg-MOF-74, which is attributed to its higher adsorption capacity for CO₂ and reduced recombination of photogenerated electron–hole pairs. In situ photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) further demonstrated that the Zn₂GeO₄/Mg-MOF-74 catalyst exhibits superior charge-transfer properties. This work may provide a useful strategy to design novel and efficient photocatalysts to reduce the atmospheric concentration of CO₂.

中文翻译：

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具有增强的CO ₂还原光催化活性 的Zn ₂ GeO ₄ / Mg-MOF-74复合材料的合成与表征†

几十年来已经研究了有效增强CO ₂的光还原的策略。在这项工作中，通过水热法制备了Zn ₂ GeO ₄ / Mg-MOF-74复合材料。X射线衍射（XRD）模式，扫描电子显微镜（SEM）图像和透射电子显微镜（TEM）图像证明了Zn ₂ GeO ₄ / Mg-MOF-74复合材料的成功合成。红外光谱和TEM图像表明Zn ₂ GeO ₄与Mg-MOF-74之间存在紧密的相互作用，这归因于吸附在Zn ₂ GeO ₄上的四甲基氢氧化铵（TMAOH）。并与Mg-MOF-74中的2,5-二氧化物-1,4-苯二甲酸（H ₄ DOBDC）相互作用。CO _2的吸附等温线表明，将Mg-MOF-74掺入Zn ₂ GeO ₄纳米棒中可改善对CO ₂的吸附。与单一的Zn ₂ GeO ₄或锌的物理混合物相比，仅以水作为牺牲剂，水热制备的Zn ₂ GeO ₄ / Mg-MOF-74催化剂具有优异的CO ₂转化为一氧化碳的性能。₂ GeO ₄ / Mg-MOF-74，这归因于其对CO的更高吸附能力₂和减少了光生电子-空穴对的重组。原位光致发光（PL）和电化学阻抗谱（EIS）进一步证明，Zn ₂ GeO ₄ / Mg-MOF-74催化剂表现出优异的电荷转移性能。这项工作可能为设计新颖有效的光催化剂以降低大气中的CO ₂浓度提供有用的策略。