Highly flexible, stretchable, patternable, transparent copper fiber heater on a complex 3D surface

A highly transparent, flexible, stretchable and patternable copper fiber heater was successfully fabricated for potential use in smart windows and other applications. The thickness of the electrospun polymer nanofibers was controlled during subsequent copper plating by adjusting the electroplating time, with minimal sacrifice in transparency. Self-fused junctions, formed via electroplating, significantly reduced the contact resistance between the intersecting copper-plated fibers. The heater temperature remained constant up to 300% sheet stretching. De-icing tests confirmed the potential applicability of such heaters in smart windows or vehicle defrosters. The copper-plated fibers may be transferred onto any surface with a complex 3D structure, as demonstrated by fabricating a heat-radiating Venus statue covered with the copper-plated fibers. The highest temperature of 328 °C was achieved by using a transparent fibrous film having 90% transparency and 0.058 Ω sq^-1 sheet resistance.