Fig. 5: The as-prepared EM wave-electricity harvester.

a Schematic illustration of EM wave reflection on the PL and Sn@C interlayer; b atomic force microscope (AFM) images of Sn@C before and after depositing PL layer (scale bar 50 μm); the inset showing the corresponding surface condition observed by FESEM (scale bar 10 μm). c Time-dependent of open-circuit voltage, d output voltage-current, e output power and f power density for the EM wave-electricity harvester. Note that the changed voltage and current could be recorded by tuning the load resistance from 0~1000 Ω.