Ever since the discovery and development of polyoxometalates (POMs), it has been known that they can exist in electron-rich reduced forms of different archetypes, structural flexibilities and functionalities. There are now reliable synthetic strategies for electron-rich POMs — materials that have unique and potentially useful catalytic, electronic and magnetic properties. This Review covers the synthesis and applications of these reduced species, and also highlights their differences and advantages relative to fully oxidized POMs. More than 200 reduced POM structures are described in this Review, with emphasis placed on how reduction influences POM structure, function and properties.

自从发现和开发多金属氧酸盐（POM）以来，人们就知道它们可以以电子丰富的还原形式存在，这些还原形式具有不同的原型，结构灵活性和功能性。对于富电子的POM，现在有可靠的合成策略-具有独特且潜在有用的催化，电子和磁性性质的材料。这篇综述涵盖了这些还原物种的合成和应用，并着重介绍了它们相对于完全氧化的POM的区别和优势。本综述描述了200多种简化的POM结构，重点放在简化如何影响POM结构，功能和特性上。