Miniature
energy storage devices simultaneously combining
high
energy output and bioavailability could greatly promote the practicability
of green, safe, and nontoxic in vivo detection, such as for noninvasive
monitoring or treatment in the gastrointestinal tract, which is still
challenging. Herein, we report ingestible and nutritive zinc-ion-based
hybrid micro-supercapacitors (ZMSCs) consisting of an edible active
carbon microcathode and zinc microanode, which can be inserted into
a standard-sized capsule and ingested in a pig stomach. With features
including flexibility, light weight, and shape adaptability, a single
microdevice displays a high energy density of 215.1 μWh cm–2, superior to that of state-of-the-art biocompatible
SCs/MSCs and even traditional ZMSCs reported previously. It also delivers
an areal capacitance of 605 mF cm–2 and a high working
voltage of 1.8 V, exceeding that of miniaturized commercial button
batteries (1.55 V, RENATA 337). Comprehensive studies in vivo and
in vitro demonstrate that the ZMSCs with high biocompatibility and
safety not only power electronic equipment in the porcine stomach
without a voltage booster but also act as a nutritional supplement
of trace element zinc within the dose range, as well as the ability
of potent antibacterial activity against bacterium Escherichia coli during the discharging process.
This work provides an example for the design and fabrication of edible
energy storage devices with high performance.