Keplerate-type polyoxometalate/semiconductor composite electrodes with light-enhanced conductivity towards highly efficient photoelectronic devices

Abstract

We designed and fabricated POM/MOS composite photoelectrodes with light-enhanced conductivity. {Mo132} clusters act as a photo-induced electron acceptor/donor.

Fundamental Aspects of Xanthene Dye Aggregation on the Surfaces of Nanocluster Polyoxometalates: H‐ to J‐Aggregate Switching

“…To examine the idea that H‐dimer formation occurs in the adsorption monolayer and does not provide the conditions for multilayer sorption through π‐stacking, we determined the binding constant in POM‐RhB associates by using the Stern–Volmer equation (also, isothermal titration calorimetry could be used as an alternative technique). As was discovered, both POMs quench the RhB molecules almost completely (see the Supporting Information, Figure S4) owing to the photoinduced charge transfer from the LUMO state of RhB (−3.53 eV, based on the cyclic voltammetry data and Tauc plot for RhB, Figure S5) to the LUMO state of POM (e.g., −4.19 eV for Mo 132 ). If the Stern–Volmer binding constant is similar to a thermodynamic constant, then the quenching process should be caused by the static mechanism .…”

Polyoxometalates: Tailoring metal oxides in molecular dimension toward energy applications

“…The polyoxomolybdates that correspond to the molecular states of molybdenum oxides have been employed in dye‐sensitized solar cells . For examples, photoelectrodes have been fabricated via the attachment of keplerate‐type Mo 132 polyoxometalate to modify the TiO 2 layer, leading to a power conversion efficiency of 7.94% that is 31% higher than the TiO 2 ‐based solar cell . The inclusion of dye ligands on a polyoxomolybdate core is an effective method to extend the optical absorption regime and enhance the photoresponsiveness .…”

“…248 For examples, photoelectrodes have been fabricated via the attachment of keplerate-type Mo 132 polyoxometalate to modify the TiO 2 layer, leading to a power conversion efficiency of 7.94% that is 31% higher than the TiO 2 -based solar cell. 249 The inclusion of dye ligands on a polyoxomolybdate core is an effective method to extend the optical absorption regime and enhance the photoresponsiveness. 250,251 By attaching bodipy dyes onto Keggin-type polyoxometalates, rapid charge injection as fast as 54 picoseconds can be realized in the covalent-bond stabilized system, highlighting the importance of metal ion, ligand molecule, anchoring moiety, and spacer length on the transient phenomena.…”

A Strategy for Breaking Polyoxometalate‐based MOFs To Obtain High Loading Amounts of Nanosized Polyoxometalate Clusters to Improve the Performance of Dye‐sensitized Solar Cells

“…[13] Using an electron acceptora st he dopant to load onto the TiO 2 photoanode could retard the charger ecombination. [24][25][26][27] POMs,a saclass of inorganic anionic clusters, have been extensively applied in magnetism, materials science, nonlinear optics, electrical, catalysis, optical, energy,a nd medicineo wing to their redox properties, charged istribution, versatile properties, and rich topology. [20][21][22][23] Recently,p olyoxometalate (POM)h as been confirmed to act as an effective electron-transfer mediator for retarding charge pair recombination and improving the PCE of DSSCs,w here it is used as the dopant to load on the TiO 2 photoanode.…”

“…[20][21][22][23] Recently,p olyoxometalate (POM)h as been confirmed to act as an effective electron-transfer mediator for retarding charge pair recombination and improving the PCE of DSSCs,w here it is used as the dopant to load on the TiO 2 photoanode. [24][25][26][27] POMs,a saclass of inorganic anionic clusters, have been extensively applied in magnetism, materials science, nonlinear optics, electrical, catalysis, optical, energy,a nd medicineo wing to their redox properties, charged istribution, versatile properties, and rich topology. [28][29][30][31][32][33][34][35] Polyoxoanions have empty do rbitals in their structures to accept electrons withouts tructure changes.…”