Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tuning the structure of in-situ synthesized few layer graphene/carbon
  composites into nanoporous vertically aligned graphene electrodes with high
  volumetric capacitance   Few layer graphene/carbon (FLG/C) composites are prepared directly via the
rapid and simple exfoliation of expanded graphite in the presence of carbon
based natural precursors (i.e. protein, polysaccharide) in water, followed by
carbonization process. Several parameters such as nature of C-precursor, FLG/C
ratio and carbonization conditions (gas, temperature) are modified in order to
optimize the morphology, composition and porosity of FLG/C and thereby
investigate their impact on gravimetric and volumetric capacitance, their
stability and contribution of pseudocapacitance (Ps) vs. double-layer
capacitance (DL). Few composites exhibit extremely high capacitance considering
their low BET-surface area ranging in 130-260 m2/g. The highest gravimetric and
volumetric capacitance of 322 F/g and 467 F/cm3 respectively (0.5 A/g); and
energy/power performance is reached for FLG/C:1/2, synthesized from
graphite-bovine serum albumin(BSA). Despite relatively high theoretical
pseudocapacitance contribution of 69% (1.1V), this sample shows also high
capacity retention at high current density and elevated energy-to-power
densities. The overall great capacity performance is attributed to the high
electrochemical surface area from combined structural features: nanoporosity,
FLG alignment with high accessibility of FLG edges and elevated packing
density.

35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th