  Entering a new era of sustainable energy generation and consumption, new
solutions for powering consumer electronics are required to tackle the limited
capacity provided by the portable power sources employed nowadays.
Hydrocarbon-fed micro-fuel cells represent a promising technology for this
purpose, and micro-reactor technology can indeed enable their integration for
portable applications. In this work, we present the design and fully scalable
wafer-level fabrication of a MEMS-based catalytic micro-reactor, paving the way
towards on-board hydrogen production for portable power generators. The device
consists of an array of thousands of vertically-aligned micro-channels, 500 um
in length and 50 um in diameter, for an overall superficial area per unit
volume of 120 cm2 cm-3 and it embeds a thin-film heater for efficient reaction
start-up. Functionalization of the active area was achieved by atomic layer
deposition, resulting in the uniform coating of a Pt/Al2O3 heterogeneous
catalyst. The temperature-dependent dimethyl ether (DME)-to-syngas conversion
is tested through steam reforming (SR) and partial oxidation (POX) reactions.
Here, conversion rates up to 74% and hydrogen selectivity of 60% are obtained
by steam reforming at 650dC, while a specific volumetric hydrogen production of
4.5 mLH2 mL-1DME cm-3REACTOR at 600dC is obtained from DME POX in a standalone
device tested by means of a 3D printed ceramic housing.
