School of Chemistry, University of Glasgow, University Avenue, Glasgow, G12 8QQ, U.K.
J Am Chem Soc. 2021 Dec 8;143(48):20059-20063. doi: 10.1021/jacs.1c10198. Epub 2021 Nov 23.
Giant polyoxomolybdates are traditionally synthesized by chemical reduction of molybdate in aqueous solutions, generating complex nanostructures such as the highly symmetrical spherical {Mo} and {Mo}, ring-shaped {Mo} and {Mo}, and the gigantic protein sized {Mo}, which combines both positive and negative curvature. These complex polyoxometalates are known to be highly sensitive to reaction conditions and are often difficult to reproduce, especially {Mo}, which is often produced in yields far below 1%, meaning further investigation has always been limited. While the electrochemical properties of these materials have been studied, their electrochemical synthesis has not been explored. Herein, we demonstrate an alternative reliable synthetic method by means of electrochemistry. By using electrochemical synthesis, we have shown the synthesis of various reported polyoxomolybdates, along with some unreported structures with unique features that have yet to be reported by traditional synthetic methods. The six different giant polyoxomolybdates that were obtained via electrochemical synthesis range from the spherical {MoFe} and {Mo} to the ring-shaped {Mo} and {Mo}, as well as the largest known polyoxometalate {Mo}, with improved yield (up to 26.1% for {Mo}), increased reproducibility, and shorter crystallization time compared to chemical reduction methods.
多金属氧酸盐通常通过在水溶液中还原钼酸盐来合成，生成复杂的纳米结构，如高度对称的球形{Mo}和{Mo}、环形{Mo}和{Mo}以及巨大的蛋白尺寸的{Mo}，它结合了正曲率和负曲率。众所周知，这些复杂的多金属氧酸盐对反应条件非常敏感，而且通常难以重现，特别是{Mo}，其产率通常远低于 1%，这意味着进一步的研究一直受到限制。虽然这些材料的电化学性质已经得到了研究，但它们的电化学合成尚未得到探索。在此，我们通过电化学方法证明了一种替代的可靠合成方法。通过电化学合成，我们已经展示了各种已报道的多金属氧酸盐的合成，以及一些具有独特特征的未报道结构，这些结构尚未通过传统合成方法报道。通过电化学合成获得的六种不同的巨型多金属氧酸盐，范围从球形{MoFe}和{Mo}到环形{Mo}和{Mo}，以及已知最大的多金属氧酸盐{Mo}，与化学还原方法相比，产率提高（高达 26.1%的{Mo}）、重现性提高、结晶时间缩短。
