Chelator-engineered nano-electroless copper coatings on epoxides: surface and electrochemical properties

This investigation explores the electroless deposition of copper nanoparticles onto epoxy substrates
using glyoxylic acid as the reducing agent. The deposition process was conducted under alkaline
conditions, with the pH precisely maintained at 11.0 ± 0.25 using potassium hydroxide. Two distinct
methanesulphonate bath formulations were employed with glucose and fructose as chelators
to enhance complexation efficiency. Azole-based stabilizers, Aminopyrazole and Tolytriazole
were introduced to fine-tune bath parameters and improve deposition control. Comprehensive
characterization of the resulting copper coatings was performed using scanning electron microscope-
energy dispersive X-ray analysis (SEM-EDAX), atomic force microscopy (AFM), X-ray photoelectron
spectroscopy (XPS), cyclic voltammetry (CV), tafel analysis, and electrochemical impedance
spectroscopy (EIS). The bath containing glucose as the chelator demonstrated superior stability and
yielded high-quality, uniform copper deposits with enhanced surface and electrochemical properties.
The novelty of this work is the addition of a chelating agent to the electroless copper deposition
process on polymeric substrates, which offers a more sustainable and environmentally friendly
method while providing better adhesion, refined grain morphology, and improved electrochemical
performance when compared to traditional surface treatments