Figure 1

(A) Scanning electron microscopy (SEM) image of the Au/Ir motor. (B,C) Energy-dispersive X-ray (EDX) spectroscopy images illustrating the distribution of the gold inner core and iridium catalytic patch, respectively.
(A) Scanning electron microscopy (SEM) image of the Au/Ir motor. (B,C) Energy-dispersive X-ray (EDX) spectroscopy images illustrating the distribution of the gold inner core and iridium catalytic patch, respectively.