  The emerging new paradigm of technologies, the internet of things, entails a
process of device miniaturization to combine several functional components,
such as sensors, actuators, and powering elements, in a single individual
on-chip platform. An essential requirement is for the devices to have a small
footprint and thus to be extended over three-dimensions to present adequate
performance. A suitable technique to realize devices of complex architectures
and virtually any size is three-dimensional printing. So far its use has seen
applications exclusively at the macroscale. Here we report the first 3D printed
architectures via robocasting of two-dimensional atomically thin transition
metal dichalcogenides demonstrating their use as miniaturizable
supercapacitors. The structures are fabricated via direct printing of a liquid
ink of chemically exfoliated 2D nanosheets. The 3D printed architectures
present footprints in the mm2 scale and micron-sized features and they
demonstrate mechanical robustness and chemical stability. They exhibit areal
capacitance of 1450 mF/cm2, rivalling and surpassing comparable devices.
Microsupercapacitors comprising two-dimensional atomically thin sheets can
enable miniaturization and upscaleable production technologies for wide-scale
adoption.
