  The advances in the mass scale manufacturing of microscale energy storage
devices via inkjet printing rely on the development of high-quality printable
ink. The earth-abundant, non-toxic carbon materials such as graphene, carbon
nanotube (CNT), reduced graphene oxide (r-GO) have shown excellent
electrochemical performance and thus garnered significant interest as suitable
electrode material. Here we report the formulation of printable graphene
aerogel ink and the fabrication of the micro-supercapacitors ({\mu}-SCs) on
flexible polyimide substrates via inkjet printing method. The advantage of
using pristine graphene aerogel intends to avoid the complex processing steps
and the use of toxic chemicals in the ink formulation and lower the
concentration of other additive components. Thus, a higher loading of active
functional material in the printable ink is achieved. The aerogel ink directly
employed to write the interdigitated {\mu}-SCs devices on a flexible polyimide
substrate at room temperature via inkjet printing. The electrochemical
performance measured using the organic ionic liquid in the voltage range of 0-1
volt. These printed {\mu}-SCs showed an areal capacity of 55 {\mu}F/cm2 at a
current density of 6 micro-amp/cm2. The printed devices showed good stability,
with ~80% of capacity retention after 10,000 cycles. Contrary to the
graphene-based {\mu}-SCs, the aerogel micro-supercapacitors do not show a
significant distortion in the CV scan even at a very high scan rate of ~2Vs-1.
Thus, we propose graphene aerogel as promising electrode material for
mass-scale production of the {\mu}-SCs.
