A Reagentless Amperometric Formaldehyde-Selective Chemosensor Based on Platinized Gold Electrodes

Abstract

Fabrication and characterization of a new amperometric chemosensor for accurate formaldehyde analysis based on platinized gold electrodes is described. The platinization process was performed electrochemically on the surface of 4 mm gold planar electrodes by both electrolysis and cyclic voltamperometry. The produced electrodes were characterized using scanning electron microscopy and X-ray spectral analysis. Using a low working potential (0.0 V vs. Ag/AgCl) enabled an essential increase in the chemosensor’s selectivity for the target analyte. The sensitivity of the best chemosensor prototype to formaldehyde is uniquely high (28180 A·M−1·m−2) with a detection limit of 0.05 mM. The chemosensor remained stable over a one-year storage period. The formaldehye-selective chemosensor was tested on samples of commercial preparations. A high correlation was demonstrated between the results obtained by the proposed chemosensor, chemical and enzymatic methods (R = 0.998). The developed formaldehyde-selective amperometric chemosensor is very promising for use in industry and research, as well as for environmental control.

TiO2 hierarchical nano blooming-flower decorated by Pt for formaldehyde detection

“…The porous micro-structure provides favourable specific surface area which ensures the high reaction rate between the captured oxygen ions and adsorbed gaseous formaldehyde [5,33,34]. The assisted Pt particles plays an important role as the catalyzer which accelerates the catalytic oxidation of HCHO [27,29,30] and enhances the selectivity [35]. The TiO 2 (nano blooming-flower sphere structure) and the doped Pt particles are synthesized through hydrothermal method and it is characterized through SEM and transmission electron microscope (TEM) to verify the dimensions.…”