Co‐Dissolved Isostructural Polyoxovanadates to Construct Single‐Atom‐Site Catalysts for Efficient CO₂Photoreduction

Abstract

We explored a co-dissolved strategy to embed mono-dispersed Pt center into V 2 O 5 support via dissolving [PtV 9 O 28 ] 7À into [V 10 O 28 ] 6À aqueous solution. The uniform dispersion of [PtV 9 O 28 ] 7À in [V 10 O 28 ] 6À solution allows [PtV 9 O 28 ] 7À to be surrounded by [V 10 O 28 ] 6À clusters via a freeze-drying process. The V centers in both [PtV 9 O 28 ] 7À and [V 10 O 28 ] 6À were converted into V 2 O 5 via a calcination process to stabilize Pt center. These double separations can effectively prevent the Pt center agglomeration during the high-temperature conversion process, and achieve 100 % utilization of Pt in [PtV 9 O 28 ] 7À . The resulting Pt-V 2 O 5 single-atom-site catalysts exhibit a CH 4 yield of 247.6 μmol g À 1 h À 1 , 25 times higher than that of Pt nanoparticle on the V 2 O 5 support, which was accompanied by the lactic acid photooxidation to form pyruvic acid. Systematical investigations on this unambiguous structure demonstrate an important role of PtÀ O atomic pair synergy for highly efficient CO 2 photoreduction.

Structural Regulation of Two Polyoxometalate-Based Metal–Organic Frameworks for the Heterogeneous Catalysis of Quinazolinones

“…Polyoxometalates (POMs) are a class of functional materials assembled with polymetallic and oxide clusters, which have received considerable attention due to their versatile structures and wide applications in catalysis, coordination chemistry, materials science, biological medicine, and photochemistry. − Especially for catalysis, these materials have strong Brønsted acidity and could be used as both acid catalysts and efficient oxidation catalysts for rapid and reversible multisite oxidation–reduction transformation. , However, the features of good solubility and easily transferred structural patterns limited the application of these materials in heterogeneous catalysis. As a unique class of porous crystalline materials, metal–organic frameworks (MOFs) constructed from metal ions/clusters and well-designed organic ligands have displayed great potential due to their tunable framework patterns and stable porosity with high surface areas. − Taking these into account, POM-based metal–organic frameworks (POMOFs) could combine both the advantages of POMs and MOFs within one single system, which greatly enhances the stability of POM units to exploit their catalytic properties.…”

“…12−18 Especially for catalysis, these materials have strong Brønsted acidity and could be used as both acid catalysts and efficient oxidation catalysts for rapid and reversible multisite oxidation−reduction transformation. 19,20 However, the features of good solubility and easily transferred structural patterns limited the application of these materials in heterogeneous catalysis. As a unique class of porous crystalline materials, metal−organic frameworks (MOFs) constructed from metal ions/clusters and well-designed organic ligands have displayed great potential due to their tunable framework patterns and stable porosity with high surface areas.…”

A study of the antioxidant properties of Keggin-type polyoxometalates

“…POMs have been widely used as catalysts [18][19][20] for organic oxidations due to their rich redox chemistry. 21 Meanwhile, a new separation technique has been developed by controlling the pore structure in a POM cluster. 22 It has been reported that many transition metal-incorporating polyoxometalates (POMs) exhibit reversible redox behaviour.…”

Designing a binuclear copper center-incorporated photocatalyst to simulate enzyme catalysis in aerobic hydroxylation of phenylboronic acids

“…Polyoxometalates (POMs) are a class of excellent photocatalysts because they can act as electronic sponges in storing or releasing electrons through redox reactions, which are favorable for efficient electron transfer through type I reactions and generating the single ROS • O 2 − . [30][31][32][33] In particular, the Dawson-type polyanion [P 2 W 18 O 62 ] 6− can accept up to 18 protons and electrons in water, displaying outstanding proton-coupled electron redox activity. 34,35 It is an exciting challenge to introduce the active center of binuclear metal monooxygenase, photosensitizer TPT and electronic sponge POM to construct a POMOF-based artificial monooxygenase model by utilizing the crystal engineering strategy (Scheme 1).…”

“…Polyoxometalates (POMs) are a class of excellent photocatalysts because they can act as electronic sponges in storing or releasing electrons through redox reactions, which are favorable for efficient electron transfer through type I reactions and generating the single ROS ˙O 2 − . 30–33 In particular, the Dawson-type polyanion [P 2 W 18 O 62 ] 6− can accept up to 18 protons and electrons in water, displaying outstanding proton-coupled electron redox activity. 34,35…”