Microscale supercapacitors provide an important complement
to batteries in a variety of applications, including portable electronics.
Although they can be manufactured using a number of
printing and lithography techniques1¨C3, continued improvements
in cost, scalability and form factor are required to
realize their full potential. Here, we demonstrate the scalable
fabrication of a new type of all-carbon, monolithic supercapacitor
by laser reduction and patterning of graphite oxide films.
We pattern both in-plane and conventional electrodes consisting
of reduced graphite oxide with micrometre resolution,
between which graphite oxide serves as a solid electrolyte4¨C9.
The substantial amounts of trapped water in the graphite
oxide makes it simultaneously a good ionic conductor and an
electrical insulator, allowing it to serve as both an electrolyte
and an electrode separator with ion transport characteristics
similar to that observed for Nafion membranes10,11. The resulting
micro-supercapacitor devices show good cyclic stability,
and energy storage capacities comparable to existing thinfilm
supercapacitors1.Direct laser writing of micro-supercapacitors on hydrated graphite oxide films.
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