Figure 5.

Comparison between neat and heavily I₂-doped P. phalangoides silk fibers before and after pyrolization. Left: neat silk fibers before (a) and after (b) pyrolization. Before pyrolization, individual silk fibers of diameter ∼0.5 μm were separated. After pyrolization, fiber disintegration was apparent. Right: heavily I₂-doped silk fibers before (c) and after (d) pyrolization. Before pyrolization, I₂ doping formed silk fiber bundles with an average diameter of ∼10 μm. After pyrolization, only small amount of disintegration was observed, leaving the bundles intact. The inset of (c) emphasizes the difference between the neat (a) and heavily I₂-doped silk fibers on the same scale.