Electrically Conductive Metallized Polymers by Cold Spray and Co-Electroless Deposition

Conducting coatings on polymer substrates is of particular interest in sustainable electronics. Despite great promises, current approaches have significant limitations to producing conductive layers on polymers in a sustainable, large-scale, and high-throughput manner. This study hybridizes cold spray particle deposition with a co-electroless deposition (i.e., over-plating) process to achieve high-electrically conductive metallization on polymer surfaces. The resulting conducting polymer retains its intrinsic mechanical strength while providing multifunctional engineering performances. Numerical modeling and a series of characterizations are conducted to investigate both the cold-spraying process and the performance of resultant conductive coatings on polymers. Numerical simulations on high-velocity particle impact on the polymer (i.e., polyamide) surface provide useful information for optimum cold-spraying process parameters. The microstructure of as-sprayed and over-plated samples is thoroughly examined using scanning electronic microscopy. Cyclic voltammetry results reveal that the metallized polymers are stable after multiple cycles. The resultant electrodes through the hybrid metallization technique (i.e., cold spray coupled with over-plating) are highly conductive and stable, thereby having the potential for sustainable polymer electronics.