The diverse capabilities of self‐propelled micro/nanomotors open up significant opportunities for various environmental and biomedical applications. Here, a synchronized two‐lobed bubble exhaust drives micromotor comprising a metal (cobalt and gold) sandwiched polytryptophan body (Au/poly‐Trp/Co) in a non‐curved direction. The autonomous motion is achieved through the decomposition of chemical fuel to result in a kayak‐like system. The ejected oxygen bubbles from the interfacial cobalt/polytryptophan layer, as well as the inert nature of the metal segments (Au−Co), were considered for some computational studies of the electronic properties of the composite and physical phenomena at the kayak/electrolyte interfaces, and confirmed the role of Co−Trp in the fuel decomposition. It is believed that the autonomous motion is the combined result of bubble recoil force, self‐electrophoresis, and perturbation in the interfacial hydrogen‐bond network of the poly‐Trp body and water molecules. The velocity of the micromotor in the range 23±4 to 157±17 μm s−1 at different concentrations of H2O2 from 1 % to 10 %. Depending on the method of fragmentation, it is possible to have both single and multiple motorized kayaks with lengths of 1.5 and 6 μm, respectively, that can be tailored for environmental applications.

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This work introduced a new electrochemical device for the synthesis of Fe 3 O 4 magnetic nanoparticles. It is established based on a scarified rotating cylindrical Fe anode in an alkaline aqueous medium, at room temperature, in the presence of NaCl, without any chemical agent or surfactant. This technique is easy to scale up and controllable, so that by changing the parameters such as the rotating speed, current density, electrode interval, and electrolysis time, the size and morphology of the particles can be changed. The physical properties of the Fe 3 O 4 nanoparticles, were characterized by FT-IR, SEM, VSM, DLS, and XRD methods. From the standpoint of environmental sustainability and economic efficiency, this technique's use of water as both a solvent and reactant (OH − generation), safe and cheap reagents, electricity instead of chemical reagents, room temperature and pressure, short reaction time, and scalability.