Polyoxometalate-based molecular/nano composites: Advances in environmental remediation by photocatalysis and biomimetic approaches to solar energy conversion

Polyoxometalates (POMs) have peculiar optoelectronic properties and high reduction potential, playing as excellent electron pools. Thus, during the recent decade, POMs have been increasingly recognized as important building blocks for highly efficient photocatalysts and photoelectrochemical devices by hybridizing with photofunctional semiconductor nanostructures and organic/inorganic molecules. In this review, development of various molecular and nano composites derived from POMs are discussed with regard to photocatalytic environmental remediation, hydrogen production, carbon dioxide reduction and photoelectrochemical solar cells. The mechanisms involved in photo-induced interfacial electron transfer processes and subsequent photochemical reactions are explored along with a brief description about their advances in emerging solar application areas. More fundamental information of the photocatalytic activities of the POM-based composites would be very useful in constructing next generation artificial photosynthetic systems with higher spectral response in visible region for efficient solar energy conversion into electricity and fuels.

► Fabrication of Polyoxometalates (POM)-based molecular/nano composites is reviewed.
► Their applications to photocatalytic remediation of environments are discussed.
► Their applications to solar fuels and solar cells are discussed.
► The photo-induced interfacial electron transfers in the POM-composites are explored.
► New approaches to construction of artificial photosynthetic systems are suggested.