Fabrication of novel nanozeolite-supported bimetallic PtCu nanoparticles modified carbon paste electrode for electrocatalytic oxidation of formaldehyde

In this work, a highly active X nanozeolite-supported bimetallic PtCu nanoparticles modified carbon paste electrode (PtCu-XNZ/CPE) was fabricated for the first time and its electrocatalytic activity toward formaldehyde oxidation was investigated. To do this, the NaX nanozeolite/CPE (NXNZ/CPE) was firstly prepared and then Cu2+ ions were introduced into nanozeolite structure by ion exchange followed by electrochemical reduction to Cu0. Then the partial replacement of Cu species by Pt species was achieved. The characterization of the proposed electrode was performed by energy dispersive X-ray analysis and scanning electron microscopy. Also, the performance of the as-prepared electrode toward formaldehyde electrooxidation was studied by the cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometric techniques. Furthermore, the effects of various parameters including times of ion exchange (tex) and replacement (tr) as well as long-term stability of the prepared electrode were investigated on the formaldehyde oxidation. The obtained results show that the as-prepared PtCu-XNZ/CPE indicates good electrocatalytic performance including high current and low overpotential for formaldehyde oxidation. It can be attributed to the presence of zeolites as nanoporous material on the electrode surface which provides the porous structure for bimetallic PtCu nanoparticles formation and active sites for formaldehyde oxidation.