Magnetically guided chemical locomotion of self-propelling paperbots

Self-propelling microjets with multimodal chemical and magnetic controls for motion were prepared from printed waste papers coated with MnO2 nanoparticles. Because the magnetic remote control was infused from the ferromagnetic coating of the printer ink, the nanoparticles decomposed peroxide fuel to induce locomotion by ejecting oxygen bubbles through a microjet. The paper microjets could be loaded with fluorescent rhodamine 6G (R6G), a model payload, before being remotely guided through an external magnetic field inside a fluidic environment. The reported methodology provides an economic, scalable, and biodegradable scheme for the design and development of bubble-propelled microengines, which are capable of directed locomotion.