Abstract A novel doping strategy based on paired charge compensating dopants is proposed to improve the solar thermochemical H2O and CO2 splitting performance of ceria. Density functional theory based ab initio calculations show that by co-doping trivalent and pentavalent cations into ceria the behavior of the trivalent dopant resembles that of tetravalent dopants. In this study, which investigated combinations of group IIIA and VA elements, it was found that the trivalent dopant identity has the largest effect on the reduction energy, while the pentavalent dopant only slightly modifies it. The trivalent dopant in these materials suppresses the reduction energy due to decreased ionic attraction of the trivalent cation and O2− as compared to Ce4+ and O2−. We predict relative reducing capabilities in the following decreasing order: Hf-CeO2 > ScX-CeO2 > Zr-CeO2 > YX-CeO2 > LaX-CeO2 > undoped CeO2 (where X = V, Nb or Ta). Experimental thermogravimetric analysis confirms the computational predictions.

中文翻译：

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使用成对电荷补偿掺杂剂模拟四价掺杂剂行为，以提高氧化铈的氧化还原性能，用于热化学分解 H 2 O 和 CO 2

摘要 提出了一种基于成对电荷补偿掺杂剂的新型掺杂策略，以提高氧化铈的太阳能热化学 H2O 和 CO2 分解性能。基于密度泛函理论的 ab initio 计算表明，通过将三价和五价阳离子共掺杂到氧化铈中，三价掺杂剂的行为类似于四价掺杂剂的行为。在本研究中，研究了 IIIA 族和 VA 元素的组合，发现三价掺杂剂对还原能的影响最大，而五价掺杂剂仅对其略有改变。由于与 Ce4+ 和 O2- 相比，三价阳离子和 O2- 的离子吸引力降低，因此这些材料中的三价掺杂剂抑制了还原能。我们按以下递减顺序预测相对还原能力：Hf-CeO2 > ScX-CeO2 > Zr-CeO2 > YX-CeO2 > LaX-CeO2 > 未掺杂的 CeO2（其中 X = V、Nb 或 Ta）。实验热重分析证实了计算预测。