Polypyrrole Microcontainers: Electrochemical Synthesis and Characterization

We present electrochemically controlled synthesis of polypyrrole microcontainers on electrogenerated hydrogen gas bubbles acting as a template. We performed structural characterization of the obtained microcontainers to gain insight into the growth kinetics of the polypyrrole shell. Experimental results showed that surfactant-mediated polymerization of pyrrole at the hydrogen microbubble surface under controlled electrochemical biasing led to the synthesis of various micro/nanostructures. Dependent upon the electrochemical conditions, such as the number of redox cycles and scan rate, the containers with spherical globules and bowl-like structures, which become lantern-like with increasing the number of cycles, are formed, as revealed by scanning electron microscopy. Their diameter can range between 40 and 200 μm, and wall thickness can be varied from 2 to 70 μm, depending upon the electropolymerization conditions.