Polyoxometalates@Metal-Organic Frameworks: Synthesis Strategies, Nanostructure Modulation and Application in Biomass Conversion.

ABSTRACT

Polyoxometalates@metal-organic frameworks (POMs@MOFs) have attracted much attention as multifunctional materials in biomass catalysis. Individual POMs and MOFs are hindered by their respective defects, such as poor stability and single catalytic active site, which make it difficult to realize large-scale applications. However, the combination of POMs and MOFs can be used to maximize the catalytic advantages of each. MOFs with high specific surface area and rich pore structure can effectively stabilize and uniformly disperse POMs, while the introduction of POMs also provides more catalytic possibilities for POMs@MOFs. Therefore, POMs@MOFs with ultra-high porosity, large specific surface area and excellent acid catalytic activity have unique catalytic advantages in the field of biomass catalytic conversion. In this work, we provide an overview of the current development of POMs@MOFs in the field of biomass catalysis. The synthesis strategies of POMs@MOFs are summarized and discussed, highlighting the in-situ synthesis methods. We focus on the nanostructure engineering of POMs@MOFs, and explore the "structure-property" relationship in depth. In addition, the representative work of POMs@MOFs in the catalysis of biomass derivatives is summarized. Filially, the prospects, and challenges for the future development of POMs@MOFs in the field of biomass catalysis are also presented.