arXiv subjects

Hwang-Beom Kim

Publications and source records attributed to Hwang-Beom Kim.

2 recordsLinked to original sources

arXiv2019

Diffusion mechanism of exciplex. 2. Energy transfer mechanism

Excited-state charge-transfer complexes (exciplexes) have been actively exploited in organic optoelectronic devices to improve performance; however, diffusion of exciplexes has not been actively studied despite its influence on performance due to the lack of apparent charge-transfer absorption. In the preceding paper, we studied the energy transfer (ET) from exciplexes to exciplex-forming pairs in relation to the charge-transfer absorption of the exciplex state, resulting in the exciplex diffusion. In this paper, we report that the ET takes place dominantly via the Dexter-type exchange mechanism, from the exponential decrease of the ET rate constant with separation between exciplexes.

cond-mat.mtrl-sci↗

arXiv2019

Diffusion of exciplex. 1. Energy transfer from exciplex to exciplex-forming pair

Exciton diffusion in organic films is crucial phenomenon in optoelectronic devices such as organic light-emitting diodes and organic photovoltaics. However, diffusion of exciplexes has not been actively studied despite their ever-growing importance in such devices due to the lack of apparent charge-transfer absorption, resulting in the absence of energy transfer (ET) to exciplex-forming pairs. Here, the ET from exciplexes to exciplex-forming pairs is reported by analysis of transient photo-luminescent profiles. Recent reports and our own observation of the sub-bandgap charge-transfer absorption in exciplex-forming systems support the ET from exciplexes to exciplex-forming pairs. The ET mechanism is discussed in the following paper.

physics.app-ph↗