Highly Flexible, Conductive, and Antibacterial Surfaces Toward Multifunctional Flexible Electronics

Conductive metallization of polymer surfaces, owing to the integration of unique features of dissimilar materials (i.e., polymer + metal), is becoming the central focus in flexible polymer electronics. However, fabrication of multifunctional surfaces on polymers in a high-throughput and robust manner at ambient conditions remains challenging. In this study, we employ the cold spray (CS) particle deposition technique to produce multifunctional hybrid surfaces on a flexible polymeric substrate (PET) toward flexible electronics. In this regard, soft metal particles (Sn), are deposited on the polymer surface as an "interlayer" followed by the over-coating of hard metal (Cu) film to create hybrid (Sn + Cu) surfaces. Studies on microstructure, adhesion strength, and water contact angle are conducted to characterize the resulting surface structure. By leveraging the optimum CS settings, multifunctional surfaces with promising electrical conductivity (5.96 x 10(5) S.m(-1)), flexibility, adhesive strength, and hydrophobicity (contact angle approximate to 122 degrees) were achieved. Moreover, the antibacterial performance of the surface is confirmed by the in vitro antibacterial tests in a manner that > 99% of the bacteria were inhibited. This work provides a promising strategy for high-throughput manufacturing of multifunctional surfaces (flexible + conductive + antibacterial surfaces) toward multifunctional flexible electronics.