Field Emission properties of nanocomposites of conducting polymers

Pejman Talemi

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arXiv · 1512.00148

Field Emission properties of nanocomposites of conducting polymers

Pejman Talemi

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Abstract

Nanocomposites based on graphene and carbon nanotubes dispersed in polypyrrole or poly(3,4ethylenedioxy)thiophene have been prepared and their performance as cold cathodes for field emission has been evaluated. It was found that the polymer matrix will degrade during the field emission process and result in unstable performance. Electropolymerization of the composites results in significantly better field emission performance, but the stability is still a major problem. Deposition of composites onto a stable membrane was proposed as a strategy for improving the performance of electrodes. The field emission data indicates that composites deposited on the surface of a membrane can limit the emission surface and result in lower maximum emission and higher Turn-On voltage. The lower emission current and consequently lower heat generation, in addition to the possible heat dissipation by the AAO membrane, can reduce the rate of the thermal degradation of the polymer. The membrane can also act as a physical barrier that holds nanotubes in place and allows electrons through. Thus, it can prevent shorting of the field emission cell. In this way higher emission and longer life time can be achieved.

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Pejman Talemi. 2015-12-01. Field Emission properties of nanocomposites of conducting polymers. https://arxiv.org/abs/1512.00148

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