본 연구를 통해 최근 개발된 근자외선영역대에서 발광하는 이리듐 착물인 Ir(pmb)3 (Iridium(III) Tris(1-phenyl-3-methylbenzimidazolin-2-ylidene-C,C2' ))의 합성 과정상에서 기존의 합성법과 동일한 발광 특성을 가지면서 더 효율적인 합성 방법을 제안하였다. 합성 과정에서 초음파가 투입되면서 용매에 녹지 않는 반응물의 파쇄 및 혼합을 돕고, 촉매의 활성을 향상시켜 이온 및 라디컬을 형성시키는 방법으로 최대 42.5% 합성 수율을 얻어 내었으며 이는 기존 방법 대비 약 4배 이상 향상된 결과이다. 이러한 초음파 합성법으로 합성된 Ir(pmb)3은 이성질체 별로 405 nm(면이성질체) 412 nm(자오선이성질체)의 발광 피크를 보였으며 이중 좀더 효율이 높은 자오선이성질체를 사용하여 전계 발광 소자를 제작하였다. 밴드갭이 큰 Ir(pmb)3에 적합한 호스트 물질을 UGH2, CBP, mCP 세가지 선정하여 전계발광소자를 제_x000D_ 작하였으며, 그 중 mCP를 호스트 물질로 사용한 소자의 경우가 호스트물질과 인광물질사이의 에너지전달이 가장 효율적으로 일어나 가장 높은 휘도와 효율을 보였다.

Ir(pmb)3 (Iridium(III)Tri(1-phenyl-3-methylbenzimidazolin-2-ylidene-C,C2' ) was synthesized to develop a deep blue-emitting Ir(III) complex. We suggested the ultrasonic reactor to enhance the poor reaction yield of Ir(pmb)3. The ultrasonic wave enhanced the reaction yield of Ir(pmb)3 because the ultrasound helped non-soluble reactants disperse efficiently and produced free radial during the reaction. The maximum yield of Ir(pmb)3 was 42.5%, which was 4 times higher than conventional method. Organic light emitting devices were fabricated with the synthesized mer-Ir(pmb)3 which emitted at 405 nm. A range of host materials with large bandgaps (UGH2, mCP and CBP) were tested for developing a deep blue emitting device. In case of the device with mCP as the host material, it emitted deep blue and performed quite well relative to the other host materials tested.

Organic Light Emitting Diode Phosphorescent Material Iridium(III) Complex Ultrasonic Preparation

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