Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unwanted electroless zinc plating on current collectors in zinc air
  batteries   The occurrence of metallic film deposition without external power supply on
the copper current collector of a zinc air battery half-cell containing zinc
slurry is investigated. Therefore, test specimens of miscellaneous materials
representing the current collector are immersed in a commercial available zinc
slurry as well as an in self-prepared zinc slurry. In case of copper and metals
which are more noble (silver and gold), a coating on the respective specimen is
obtained. An element mapping of the coated copper specimen is performed by
means of scanning electron microscopy (SEM) and energy dispersive x-ray
spectroscopy (EDX) identifying that the coating layer consists of zinc and
oxygen. In order to clarify the crystal structure and the exact composition,
focused ion beam (FIB) and x-ray photoelectron spectroscopy (XPS) measurements
are applied, proving that the layer consists of elemental zinc, which, is
merely oxidized on the surface. Finally, a reaction mechanism for the
reversible zinc film deposition is proposed.

24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg