SiW₁₁Fe@MIL‐101(Cr) Composite: A Novel and Versatile Electrocatalyst

Abstract

A novel composite is prepared by the incorporation of the iron‐substituted silicotungstate [SiW11FeIII(H2O)O39]5− (SiW11Fe) into the 3D structure of MIL‐101(Cr). Pyrolytic graphite electrodes are modified with SiW11Fe and the composite material SiW11Fe@MIL‐101, and the electrochemical behavior of the electrodes is studied by cyclic voltammetry. The SiW11Fe‐modified electrode shows three reduction processes: the peak at more positive potentials is assigned to FeIII→FeII and the other two peaks to WVI→WV processes. The SiW11Fe@MIL‐101‐modified electrode shows, besides the redox processes assigned to SiW11Fe, an additional peak from the MIL‐101(Cr) matrix, which corresponds to CrIII→CrII reduction. The SiW11Fe@MIL‐101‐modified electrode shows excellent tungsten‐based electrocatalytic activity towards nitrite and iodate reduction, and chromium‐based electrocatalytic properties towards ascorbic acid oxidation. It, thus, ultimately proves to be a modified electrode with multi‐electrocatalytic properties.

PMo11V@N-CNT electrochemical properties and its application as electrochemical sensor for determination of acetaminophen

“…In fact, several POM@CNT nanocompositemodified electrodes have been reported [18], with application mainly in charge-discharge phenomena [19], energy storage [20], molecular cluster batteries [21], lithium-ion batteries [22,23], capacitors [24,25] and electrocatalysis [18,26,27]. S e v e r a lP O M sh a v ea l s ob e e ni m m o b i l i z e do nm e t a lorganic frameworks [28,29], nitrogen-doped graphene [30] and, inclusively, on single-walled carbon nanotubes [26] to nitrite and iodate reduction, ascorbic acid oxidation and dopamine, acetaminophen and theophylline sensing, which shows the wide range of POM electrocatalytic action.…”

Improving the Catalytic Performance of Keggin [PW12O40]3− for Oxidative Desulfurization: Ionic Liquids versus SBA-15 Composite

“…Our research group has been developing several POM-based materials for applications in luminescence [ 18 , 19 ], gas separation [ 20 ], electrocatalysis [ 21 , 22 ], olefin oxidation [ 23 , 24 ] as well as oxidative desulfurization [ 25 , 26 ]. The preparation of organic POM hybrids has become a widespread methodology in POM chemistry [ 27 ], and in the case of catalysis, it has been used to enhance the efficiency and allow the separation of catalysts from reactional media [ 28 , 29 ].…”

Heterogenisation of polyoxometalates and other metal-based complexes in metal–organic frameworks: from synthesis to characterisation and applications in catalysis

“…12). 37 In a similar fashion than for PW11 and SiW11, the incorporation of SiW11Fe into MIL-101 leads to a change in its diffusion regime from surface-confined to solution-type behaviour. By contrast, both the anodic and cathodic peak current intensities of PMo10V2@MIL-101(Cr) were directly proportional to the scan rate, which indicated processes confined to the surface and a tighter interaction of the POM with its MOF host.…”

“…For example, the Raman spectrum of SiW11@MIL-101(Cr) exhibits a small band at ~978 cm -1 assigned to a W=O stretching mode of SiW11. 37 In P2W18Co4@MIL-101(Cr), the W=O band of the POM at 982 cm -1 is clearly visible in the Raman spectrum of the composite, although with a rather weak intensity. 62 In rare examples, the characteristic Raman bands of the catalyst are intense.…”