PANI-PAN coaxial nanofibers have been prepared by electro-spinning during polymerization. The surface of the resulting nanofibers is superhydrophobic with a water contact angle up to 164.5 degrees. Conductivity of the PANI-PAN nanofibers is about 4.3 x 10(-2) S center dot cm(-1). The superhydrophobic nanofibers show a chemical dual-responsive surface wettability, which can be easily triggered by changing pH value or redox properties of the solution. A reversible conversion between superhydrophobicity and superhydrophilicity can be performed in a short time. The strategy used here may provide an easy method to control the wettability of smart surfaces. by using properties of low-cost functional polymers. [GRAPHICS] in situ reduction, a large number of metal-based functional materials can be prepared. PVP is alkaline, and thus capable of catalyzing the sol-gel process to generate an inorganic shell. Furthermore, pre-formed nanoparticles can also be absorbed by the shell through specific interactions. The PS core is not infiltrative during synthesis, and hollow rings can be derived after the polymer templates are removed. [GRAPHICS] b