arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2006.12260cond-mat.mtrl-sci
收藏

$β$ $_2$ V $_2$ O $_7$ / $β$ $_2$ V $_2$ O $_7$固溶体光催化分解水的适用性

Suitability of $β$-Mn$_2$V$_2$O$_7$/$β$-Cu$_2$V$_2$O$_7$ solid solutions for photocatalytic water-splitting

Silviya Ninova, Michal Strach, Raffaella Buonsanti, Ulrich Aschauer

摘要:

焦钒酸盐$β$ $_2$ V $_2$ O $_7$和$β$ $_2$ V $_2$ O $_7$作为光阳极材料用于水裂解之前进行了研究.然而,他们都没有被发现是足够活跃的。在这项工作中,我们通过密度泛函理论计算来预测这两种结构相似的焦钒酸盐的固溶体的性质,以探索其能带结构对水裂解的适用性,并评估其易于合成。我们预测,高达20%的Cu或Mn分别取代到$β$ -Mn $_2$ V $_2$ O $_7$和$β$ -Mn $_2$ V $_2$ O $_7$中导致带隙变窄,这在前一情况下通过紫外-可见光谱实验证实。然而,在中间组成范围内的固溶体的计算,产生几乎恒定的带隙。此外,我们预测具有较高取代水平的固溶体越来越难以合成,这意味着具有低取代水平的固溶体在带隙和易于合成方面是最相关的。

英文摘要:

The pyrovanadates $β$-Mn$_2$V$_2$O$_7$ and $β$-Cu$_2$V$_2$O$_7$ were previously investigated as photoanode materials for water splitting. Neither of them, however, was found to be sufficiently active. In this work we predict the properties of solid solutions of these two structurally similar pyrovanadates via density functional theory calculations to explore the suitability of their band structure for water splitting and to assess their ease of synthesis. We predict that substitution of up to 20\% Cu or Mn into $β$-Mn$_2$V$_2$O$_7$ and $β$-Mn$_2$V$_2$O$_7$ respectively leads to a narrowing of the band gap, which in the former case is experimentally confirmed by UV-vis spectroscopy. Calculations for solid solutions in the intermediate composition range, however, yield nearly constant band gaps. Moreover, we predict solid-solutions with higher substitution levels to be increasingly difficult to synthesize, implying that solid solutions with low substitution levels are most relevant in terms of band gaps and ease of synthesis.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑