A new heterogeneous photocatalyst based on Wells–Dawson polyoxometalate and nickel coordination compounds: synthesis, structure and property

Abstract

Polyoxometalate (POM) as a promising photocatalyst has gained much attention for the removal of organic pollutants from water. However, the two main drawbacks of low visible-light photocatalytic activity due to wide oxygen-to-metal charge transfer band of POM and high solubility in solution make them difficult to recover and recycle impeding potential applications. We have prepared a new heterogeneous POM photocatalyst, namely [Ni(2,2 0 -bpy) 3 ] 3 [P 2 W 18 O 62 ] (2,2 0 -bpy ¼ 2,2 0 -bipyridine, NiPW), characterized by X-ray single crystal diffraction, elemental analyses, FTIR, XRPD, and UV-DRS. The photocatalyst NiPW exhibits two broad band centered at 513 nm and 770 nm, extending induced light to visible region. As a photocatalyst, NiPW composite not only shows excellent visible light photocatalytic activity for the photodegradation of methyl orange in the presence of H 2 O 2 , but also can be easily separated by simple centrifugation for its insoluble property and recycled.

Assembly of three new POM-based Ag(I) coordination polymers with antibacterial and photocatalytic properties

“…The O 2 in the reaction system can easily oxidize the reductive POM species into the active POM species for continuing to work. The photocatalytic mechanism (Scheme S2) has been studied and exposited in Supporting information [57][58][59][60][61][62]. The whole result indicates that degradation activities of compounds 1-3 on three dyes gradually increase: compound 3 4compound 2 4compound 1.…”

Polyoxometalates: Tailoring metal oxides in molecular dimension toward energy applications

“…Placing the photosensitizer adjacent to the nickel atoms in polyoxometalate has been proved to enhance the hydrogen evolution reaction with a 1476 turnover number when it is integrated into metal organic frameworks . Ni‐containing polyoxometalate with bipyridine groups has been shown to effectively absorb visible light and photodegrade the methyl orange dye, as well as suppress the undesired oxygen‐to‐metal charge transfer and water dissolving properties . Theoretical calculations have been performed to understand the structure‐activity relations of the Ni‐containing polyoxometalates toward the hydrogen evolution, which identifies the nickel inclusion as a key step toward the fuel production purpose …”

“…127 Ni-containing polyoxometalate with bipyridine groups has been shown to effectively absorb visible light and photodegrade the methyl orange dye, as well as suppress the undesired oxygen-to-metal charge transfer and water dissolving properties. 163 Theoretical calculations have been performed to understand the structure-activity relations of the Ni-containing polyoxometalates toward the hydrogen evolution, which identifies the nickel inclusion as a key step toward the fuel production purpose. 164,165…”

Yolk–shell microspheres assembled from Preyssler‐type NaP5W30O11014− polyoxometalate and MIL‐101(Cr) metal–organic framework: A new inorganic–organic nanohybrid for fast and selective removal of cationic organic dyes from aqueous media

“…Polyoxometalates (POMs) are a class of compounds formed by bulky clusters of transition metal oxide anions, which have attracted much attention due to their earth‐abundant source, rich topology and versatility, controllable shape and size, oxo‐enriched surfaces, high electronegativity, etc., with various applications in many fields, such as catalysis, optics, magnetism, biological medicine as well as dye adsorption . The strong attraction of POM polyanions to cationic dyes suggests that they are potential and suitable adsorbents for selectively capturing cationic dyes.…”