Polyoxometalate Complexes as Precursors to Vanadium‐Doped Molybdenum or Tungsten Oxide Thin Films by Means of Aerosol‐Assisted Chemical Vapour Deposition

Ponja, Sapna D.; Sathasivam, Sanjayan; Davies, Helen; Parkin, Ivan P.; Carmalt, Claire J.

doi:10.1002/cplu.201500461

Cited by 8 publications

(5 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The spectrum also contains two W 5p 3/2 signals at 41.3 and 39.0 eV, respectively. These binding energies are in good agreement with different measurements of fully oxidized W-containing POMs. − The area ratio of the two tungsten species is 90.9% fully oxidized to 9.1% reduced W atom. This thus corresponds to an atom ratio of 35 fully oxidized to four reduced W atoms.…”

supporting

confidence: 87%

Insertion of V^IVIons into the Polyoxotungstate Archetype {As₄W₄₀}

et al. 2021

View full text Add to dashboard Cite

A new polyoxometalate compound consisting of the 39-tungsto-4-arsenate(III) unit with four incorporated VIV ions, isolated as (NH4)22[(VIVO)2(VIVO(H2O))(AsIIIWVI 9O33)2(AsIIIWVI 8.5VIV 0.5(OH)O32)2(WVIO2)4]·48H2O (NH 4 -As 4 W 39 (V 4 )), was synthesized and fully characterized. SQUID magnetometry shows three weakly coupled VIV centers with an antiferromagnetic exchange interaction and one isolated VIV ion as a spin-1/2 Curie paramagnet. UV–vis spectroscopy indicates that the As 4 W 39 (V 4 ) structure remains intact in aqueous solution for at least 24 h. To enable the deposition of As 4 W 39 (V 4 ) from solution on gold surfaces, its trihexyltetradecylphosphonium salt, THTDP-As 4 W 39 (V 4 ), was prepared. The IR spectra of both congeners reveal the structural identity of As 4 W 39 (V 4 ) independent of the countercations. The X-ray absorption near-edge structure data confirm the presence of VIV centers in a distorted square-pyramidal coordination geometry in NH 4 -As 4 W 39 (V 4 ) and THTDP-As 4 W 39 (V 4 ). X-ray photoelectron spectroscopy of the latter, deposited on Au(111), shows that the 4 V and 35 W centers preserve their IV+ and VI+ oxidation states, while the remaining 4 W ions are reduced to IV+.

show abstract

supporting

confidence: 87%

Insertion of V^IVIons into the Polyoxotungstate Archetype {As₄W₄₀}

et al. 2021

View full text Add to dashboard Cite

show abstract

“…11,47,48 Mixed-metal SSP compounds are often soluble in organic solvents (and sometimes water), allowing convenient routes to fabricate thin films of CMOs, by straightforward techniques (such as drop-casting and spin-coating), 26,27,35,49,50 spray pyrolysis, 51 sol-gel processes 11,15,52 or (aerosol-assisted) CVD. 53 The use of a single precursor under mild reaction conditions also simplifies CMO synthesis for applications that demand excellent material homogeneity across a large scale. 4,26,42,54 Of course, the advantages of using an SSP may be offset by the challenges and costs of prepraring a specifically designed molecular precursor, which is an important consideration for practical use.…”

Section: Opportunities Using Mixed-metal Precursorsmentioning

confidence: 99%

“…(x = 0, 1) have been used to make Vdoped α-MoO3 and WO3 via AACVD at 550 ᵒC. 53 Polyoxoniobate clusters have also been used to produce LiNbO3 (Fig. 13), 35 and present a fascinating example of the importance of deposition and drying processes when forming (micro)crystalline films of SSPs prior to calcination.…”

Section: Mixed-metal Polyoxometallates (M-poms)mentioning

confidence: 99%

The use of mixed-metal single source precursors for the synthesis of complex metal oxides

Wright

Pike

2020

Chem. Commun.

View full text Add to dashboard Cite

show abstract

“…XPS of Vulcan, [O]V, {W 18 }@Vulcan, and {W 18 }@[O]V was performed to probe the concentrations, chemical environ- Deconvolution of the W 4f photoemission signal in the spectrum of {W 18 } reveals a doublet with peaks at 35.6 and 37.7 eV due to the W 4f 7/2 and W 4f 5/2 signals, respectively, as expected for W 6+ . 44 The high-resolution XP spectra of {W 18 }@ Vulcan and {W 18 }@[O]V exhibit peaks centered at 36.2 eV and 38.3 eV, respectively, which is also consistent with the presence of W 6+ in the materials. The O 1s peak for the POMcontaining samples is in the range of 532−533 eV, which is expected for the oxo ligands of the POMs.…”

Section: ■ Results and Discussionmentioning

confidence: 94%

Functionalization of Carbon Surfaces Tunes the Redox Stability of Polyoxometalate@Carbon Electrodes

Mughal

Walsh

Newton

2020

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

The use of redox-active polyoxometalates (POMs) offers unique opportunities for the development of advanced functional materials, but the use of such systems is often limited by their instability in operando. To enhance the functional stability of POMs they are often immobilized onto solid supports, though complex POM-hybridization strategies are usually required. Herein we describe a simple and scalable method for the fabrication of POM-based redox materials. Our method involves functionalizing inexpensive carbon black (Vulcan XC-72R) support with oxygenic groups, which act as stabilizing anchor points for the Wells-Dawson POM K6[P2W18O62]. X-ray photoelectron spectroscopy and electron microscopy confirm that oxidation of the carbon surfaces promotes interactions between the POMs and the carbon surface. Scanning electron microscopy shows that the surface area of the Vulcan decreases upon oxidation and this is confirmed by Brunauer-Emmett-Teller analysis, where the specific surface area of the carbon decreases from 234 m 2 g -1 to 108 m 2 g -1 . Solid-state voltammetry shows that the electrochemical properties of the POMs are retained by the hybrid material. Four successive, reversible reductions of the attached POMs are observed when the composite is in contact with 1.0 mol dm -3 H2SO4, corresponding to theIn contrast, formation of a composite using unoxidized carbon only shows the [P2W18O62] 6-/[P2W18O62] 8-, [P2W18O62] 8-/[H2P2W18O62] 8-, and [H2P2W18O62] 8-/[H4P2W18O62] 8-couples. Finally, voltammetric analysis shows that the composite formed using the oxidized carbon shows very little degradation in any of its 4 redox process over 500 charging/discharging cycles, whereas that formed using unoxidized carbon almost completely loses its redox activity after 250 cycles. These observations have significant implications for the sustainable synthesis of functional molecular redox materials for future energy-storage technologies.

show abstract

Polyoxometalate Complexes as Precursors to Vanadium‐Doped Molybdenum or Tungsten Oxide Thin Films by Means of Aerosol‐Assisted Chemical Vapour Deposition

Cited by 8 publications

References 46 publications

Insertion of V^IVIons into the Polyoxotungstate Archetype {As₄W₄₀}

Insertion of V^IVIons into the Polyoxotungstate Archetype {As₄W₄₀}

The use of mixed-metal single source precursors for the synthesis of complex metal oxides

Functionalization of Carbon Surfaces Tunes the Redox Stability of Polyoxometalate@Carbon Electrodes

Contact Info

Product

Resources

About

Polyoxometalate Complexes as Precursors to Vanadium‐Doped Molybdenum or Tungsten Oxide Thin Films by Means of Aerosol‐Assisted Chemical Vapour Deposition

Cited by 8 publications

References 46 publications

Insertion of VIVIons into the Polyoxotungstate Archetype {As4W40}

Insertion of VIVIons into the Polyoxotungstate Archetype {As4W40}

The use of mixed-metal single source precursors for the synthesis of complex metal oxides

Functionalization of Carbon Surfaces Tunes the Redox Stability of Polyoxometalate@Carbon Electrodes

Contact Info

Product

Resources

About

Insertion of V^IVIons into the Polyoxotungstate Archetype {As₄W₄₀}

Insertion of V^IVIons into the Polyoxotungstate Archetype {As₄W₄₀}