Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low work function thin film growth for high efficiency thermionic energy
  converter: Coupled Kelvin probe and photoemission study of potassium oxide   Recent researches in thermal energy harvesting have revealed the remarkable
efficiency of thermionic energy converters comprising very low work function
electrodes. From room temperature and above, this kind of converter could
supply low power devices such as autonomous sensor networks. In this type of
thermoelectric converters, current injection is mainly governed by a mechanism
of thermionic emission at the hot electrode which explains the interest for low
work function coating materials. In particular, alkali metal oxides have been
identified as excellent candidates for coating converter electrodes. This paper
is devoted to the synthesis and characterization of potassium peroxide K2O2
onto silicon surfaces. To determine optimal synthesis conditions of K2O2, we
present diagrams showing the different oxides as a function of temperature and
oxygen pressure from which phase stability characteristics can be determined.
From the experimental standpoint, we present results on the synthesis of
potassium oxide under ultra high vacuum and controlled temperature. The
resulting surface is characterized in situ by means of photoemission
spectroscopy (PES) and contact potential difference (CPD) measurements. A work
function of 1.35 eV is measured which and the expected efficiency of the
corresponding converter is discussed. It is generally assumed that the decrease
of the work function in the alkali/oxygen/ silicon system, is attributed to the
creation of a surface dipole resulting from a charge transfer between the
alkali metal and oxygen.

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The categories of this paper are: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: econ
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The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an
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The categories of this paper are: ao-sci
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph