Polyaniline-coated glassy carbon microspheres decorated with nano-palladium as a new electrocatalyst for methanol oxidation

Abstract

• A composite electrocatalyst platform was decorated with nanoPd. • The 3D electrocatalyst was easy to fabricate. • The fabricated catalyst showed high catalytic activity and stability toward methanol oxidation reaction. We propose a 3D catalyst of polyaniline-coated glassy carbon microspheres decorated with nano-palladium (3D nanoPd@PANi/GCM) for methanol oxidation in direct methanol fuel cells (DMFCs). The 3D nanoPd@PANi/GCM catalyst was synthesized by a green, low-cost method using two-step chemical deposition. The surface morphology and structure of the 3D catalyst were characterized by scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared spectrometry (FTIR), and X-ray diffractometry (XRD). Electrochemical properties were evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA). The 3D nanoPd@PANi/GCM catalyst exhibited a larger effective surface area, higher specific activity and catalytic stability, and more durability than a commercial Pd/C catalyst for methanol oxidation. The novel catalyst showed great potential as a new electrode material for DMFCs.