Formaldehyde Electro‐catalytic Oxidation onto Carbon Paste Electrode Modified by MIL‐101(Cr) Nanoparticles

Abstract

AbstractIn this paper, MIL‐101(Cr) metal‐organic framework (MOF) has been rapidly synthesized via microwave heating and fully characterized using powder X‐ray diffraction (PXRD), field emission scanning electronic microscopy (FESEM), Fourier transform infrared (FT‐IR) and nitrogen adsorption/desorption isotherm. FESEM image of MIL‐101(Cr) MOF displays spherical particles with a uniform morphology and particle size under 100 nm. The BET surface area and average pore diameter of synthesized MIL‐101(Cr) MOF were obtained to be 7.266 × 102 m2 g−1 and 3.28 nm, respectively. Nickel hydroxide dispersed onto MIL‐101(Cr) nanoparticles modified carbon paste electrode (Ni(OH)2‐MIL/CPE) was employed for electro‐catalytic oxidation of formaldehyde (CH2O) in the alkaline medium. The mean value of electron‐transfer coefficient, charge‐transfer rate constant and surface coverage of the Ni(OH)2‐MIL/CPE are found to be 0.517, 0.0058 s−1 and 7.88 × 10−8 mol cm−2, respectively. Also, the mean value of catalytic rate constant and diffusion coefficient of CH2O in the modified electrode surface are calculated to be 2.37 × 102 cm3 mol−1 s−1 and 1.288 × 10−6 cm2 s−1, respectively. The results indicate that Ni(OH)2‐MIL/CPE displays good electrocatalytic activity to the CH2O oxidation owing to porous structure and the large surface area of MIL‐101(Cr) MOF.