Fig. 6.

(a) Photograph of a full wave rectifying circuit built with biodegradable materials, including Si NM, Mg, SiO₂ and silk substrate; (b) Image of the full wave rectifying circuit wirelessly powering an LED with a Mg RF receiver; (c) Dissolution of a rectifying circuit in DI water after 1 and 60 min; (d) Schematic illustration of a battery system with 4 Mg-Mo cells in series; (e) Performance of a battery system with 4 Mg-Mo cells (discharge current density 0.1 mA cm⁻²); (f) Images of the dissolution of a battery system at various stages in phosphate buffered saline. Reprinted with permissions from Refs. [20, 21].