京都大学 · Engineering
히로노리 카지 교수의 연구실은 유기 발광 소자(OLED)의 고효율 및 저비용 구현을 위한 첨단 유기 반도체 재료 개발에 중점을 두고 있습니다. 주요 연구 방향은 열활성화된 지연형 발광(TADF) 소재의 설계 및 응용으로, 특히 금속을 포함하지 않은 메탈프리 TADF 물질과 고해상도 청색 발광 소재의 개발에 기여하고 있습니다. 또한, 전하 이동 메커니즘과(exciton 동역학), 분자 간 상호작용을 통한 에너지 전달 메커니즘의 최적화를 통해 효율성과 수명을 동시에 향상시키는 기초 연구도 진행 중입니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Efficient organic light-emitting diodes have been developed using emitters containing rare metals, such as platinum and iridium complexes. However, there is an urgent need to develop emitters composed of more abundant materials. Here we show a thermally activated delayed fluorescence material for organic light-emitting diodes, which realizes both approximately 100% photoluminescence quantum yield and approximately 100% up-conversion of the triplet to singlet excited state. The material contains
Highly efficient solution-processable emitters, especially deep-blue emitters, are greatly desired to develop low-cost and low-energy-consumption organic light-emitting diodes (OLEDs). A recently developed class of potentially metal-free emitters, thermally activated delayed fluorescence (TADF) materials, are promising candidates, but solution-processable TADF materials with efficient blue emissions are not well investigated. In this study, first the requirements for the design of efficient deep
Inter- and intramolecular charge-transfer processes are combined using an exciplex-forming host and a thermally activated delayed fluorescent dopant, for fabricating efficient fluorescent organic light-emitting diodes along with the reduced efficiency roll-off at high current densities. Extra conversion on the host from triplet exciplexes to singlet exciplexes followed by energy transfer to the dopant reduces population of triplet excitons on dopant molecules, thereby reducing the triplet excito
Conspectus“Dynamic exciton”, an umbrella term concept in photochemistry, plays an important role in nature, science, and technology, especially in photoinduced and electrically induced electron transfer (ET) between a donor (D) and an acceptor (A). Typically, an exciton in molecular D–A systems is considered a locally excited (LE) state of a donor (D*) or an acceptor (A*) molecule, but let us extend the terminology of “exciton” to an integrated class of LE, charge-transfer (CT), and charge-separ
The isomeric states and intermolecular packing of tris(8-hydroxyquinoline) aluminum(III) (Alq(3)) in the alpha-, gamma-, and delta-crystalline forms and in the amorphous state, which are important for understanding the light-emitting and electron-transport properties, have been analyzed by CP/MAS (13)C NMR. This simple NMR experiment shows that the isomeric state of alpha- and amorphous Alq(3) is meridional, whereas that of gamma- and delta-Alq(3) is facial. In the amorphous Alq(3), the inclusio
A novel thermally activated delayed fluorescent (TADF) compound, 9-(3-((4,6-diphenyl-1,3,5-triazin-2-yl)oxy)phenyl)-3,6-diphenyl-9 H-carbazole (PhCz- o-Trz), with a donor-σ-acceptor (D-σ-A) motif is developed. A flexible small space σ-junction is adopted to partly suppress the intramolecular charge transfer (intra-CT) while inversely enhancing the intermolecular charge transfer (inter-CT) between D/A moieties, realizing the coexistence of both intra-CT and inter-CT in an amorphous aggregate. The
