Periodic Oscillatory Motion of a Self-Propelled Motor Driven by Decomposition of H 2 O 2 by Catalase.

A self-propelled motor driven by the enzymatic reaction of catalase adsorbed onto a filter paper floating on an aqueous solution of H2 O2 was used to study nonlinear behavior in the motor's motion. An increase in the concentration of H2 O2 resulted in a change from no motion to irregular oscillatory motion, periodic oscillatory motion, and continuous motion. The mechanisms underlying oscillation and mode bifurcation are discussed based on experimental results on O2 bubble formation and growth on the underside of the motor.