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

Abstract

Abstract A novel composite is prepared by the incorporation of the iron‐substituted silicotungstate [SiW 11 Fe III (H 2 O)O 39 ] 5− (SiW 11 Fe) into the 3D structure of MIL‐101(Cr). Pyrolytic graphite electrodes are modified with SiW 11 Fe and the composite material SiW 11 Fe@MIL‐101, and the electrochemical behavior of the electrodes is studied by cyclic voltammetry. The SiW 11 Fe‐modified electrode shows three reduction processes: the peak at more positive potentials is assigned to Fe III →Fe II and the other two peaks to W VI →W V processes. The SiW 11 Fe@MIL‐101‐modified electrode shows, besides the redox processes assigned to SiW 11 Fe, an additional peak from the MIL‐101(Cr) matrix, which corresponds to Cr III →Cr II reduction. The SiW 11 Fe@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.