Efficiency Control in Iridium Complex-Based Phosphorescent Light-Emitting Diodes

<table>Excitons confinement in the emissive layer by the adjacent layer, <svg height="15.65" id="M3" style="vertical-align:-3.39064pt" version="1.1" viewbox="0 0 33.049999 15.65" width="33.049999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> is the energy barrier for electrons, and <svg height="15.5125" id="M4" style="vertical-align:-3.276pt" version="1.1" viewbox="0 0 34.349998 15.5125" width="34.349998" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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l14 20.5t15 23.5t13.5 21.5l29 -10q-52 -129 -71 -163h-500l6 28q66 4 83 17.5t28 73.5l77 409q11 61 -0.5 75.5t-78.5 18.5l10 28h467z" id="x1D438"></path></g>
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</svg> the energy barrier for the holes with charge trapping.</table>

Advances in Materials Science and Engineering

fig2

Figure 2

Figure 2: Efficiency Control in Iridium Complex-Based Phosphorescent Light-Emitting Diodes 