Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superionic state in double-layer capacitors with nanoporous electrodes   In the recent experiments [Chmiola et al, Science 313, 1760 (2006); Largeot
et al, J. Am. Chem. Soc. 130, 2730 (2008)] an anomalous increase of the
capacitance with a decrease of the pore size of a carbon-based porous electric
double-layer capacitor has been observed. We explain this effect by the image
forces which exponentially screen out the electrostatic interactions of ions in
the interior of a pore. Packing of ions of the same sign becomes easier and is
mainly limited by steric interactions. We call this state `superionic' and
suggest a simple model to describe it. The model reveals a possibility of a
voltage-induced first-order transition between a cation(anion)-deficient phase
and a cation(anion)-rich phase which manifests itself in a jump of capacitance
as a function of voltage.

33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org