Hollow polyaniline microspheres have been synthesized from a monomeric aniline-based template, which makes template removal unnecessary. The template for the microstructures is an aniline emulsion with β-naphthalenesulfonic acid (NSA) as dopant, and ammonium persulfate (APS) as oxidizer. The Figure is a TEM image of polyaniline/NSA spheres obtained from 0.2 M aniline at an NSA/aniline/APS ratio of 1:4:4.