김세훈 교수

White-light-emitting single molecules are promising materials for use in a new generation of displays and light sources because they offer the possibility of simple fabrication with perfect color reproducibility and stability. To realize white-light emission at the molecular scale, thereby eliminating the detrimental concentration- or environment-dependent energy transfer problem in conventional fluorescent or phosphorescent systems, energy transfer between a larger band-gap donor and a smaller

We have designed and synthesized asymmetric cyano-stilbene derivatives containing trifluoromethyl (-CF(3)) substituents with the aim of producing tightly packed pi-dimer systems that as crystals exhibit reversible [2 + 2] cycloaddition with characteristic fluorescence modulation. (Z)-3-(3',5'-Bis(trifluoromethyl)biphenyl-4-yl)-2-(4'-(trifluoromethyl)biphenyl-4-yl)acrylonitrile (CN(L)-TrFMBE) and its derivatives were found to form antiparallel pi-dimer stacks in crystals due to their specific int

Phenothiazine derivatives with various conjugated linkers (furan, thiophene, and 3,4-ethylenedioxythiophene) were synthesized and used in dye-sensitized solar cells to study the effect of conjugated linkers on device performance. Among them, one with furan as a conjugated linker showed a solar energy-to-electricity conversion efficiency (η) of 6.58%, an improvement of over 24% compared with the T2-1 reference cells' 5.29% under AM 1.5 G irradiation.

New anthracene-based deep-blue emitting molecular glass, 9-(9-phenylcarbazole-3-yl)-10-(naphthalene-1-yl)anthracene (PCAN), which is asymmetrically functionalized with N-phenylcarbazole and naphthalene, has been designed, synthesized, and characterized. The deep-blue emitting PCAN is efficiently secured for color purity, has high glass transition temperature (Tg = 151 °C), and has excellent solubility (>100 mg mL−1 in toluene), due to its highly tilted asymmetric molecular conformation. Using pr

Abstract The unique and unprecedented electroluminescence behavior of the white‐emitting molecule 3‐(1‐(4‐(4‐(2‐(2‐hydroxyphenyl)‐4,5‐diphenyl‐1H‐imidazol‐1‐yl)phenoxy)phenyl)‐4,5‐diphenyl‐1H‐imidazol‐2‐yl)naphthalen‐2‐ol (W1), fluorescence emission from which is controlled by the excited‐state intramolecular proton transfer (ESIPT) is investigated. W1 is composed of covalently linked blue‐ and yellow‐color emitting ESIPT moieties between which energy transfer is entirely frustrated. It is demon

High performance deep-blue organic light-emitting diodes (OLEDs) have been investigated using new multifunctional blue emitting materials 3-(anthracen-9-yl)-9-ethyl-9H-carbazole (AC), 3,6-di(anthracen-9-yl)-9-ethyl-9H-carbazole (DAC), 3-(anthracen-9-yl-)-9-phenyl-9H-carbazole (P-AC), and 3,6-di(anthracen-9-yl)-9-phenyl-9H-carbazole (P-DAC) which comprise covalently bonded carbazole and anthracene moieties. We also have investigated the thermal, electrochemical, and morphological stability to fin

Abstract Aiming for highly efficient blue electroluminescence, we have designed and synthesized a novel class of tetraphenylimidazole‐ based excited‐state intramolecular proton‐transfer (ESIPT) molecules with covalently linked charge‐transporting functional groups (carbazole‐ and oxadiazole‐functionalized hydroxyl‐substituted tetraphenylimidazole (HPI), i.e., HPI‐Cbz and HPI‐Oxd, respectively). High T g (ca. 130 °C) amorphous films of HPI‐Cbz and HPI‐Oxd showed intense and ideal blue‐light emiss

Efficient blue electrophosphorescence was achieved from iridium(III) bis[(4,6-difluorophenyl)pyridinato- N, C 2 ‘]picolinate (FIrpic) covalently bonded to the carbazole-based wide-band-gap polymer host (poly(9-dodecyl-3-vinylcarbazole); CP 0 ). Number-average molecular weights of CP 0 -based copolymers containing FIrpic pendants (CP n ) ranged over 18 000−33 700 when the molar content of FIrpic-containing monomer units was 0.8−10.6%: CP 1 (0.8%), CP 2 (2.9%), CP 3 (5.3%), and CP 4 (10.6%). Phase

본 연구는 쇠퇴현상을 겪고 있는 구시가지를 대상으로 빈집 발생의 원인 및 특성을 미시적 측면에서 분석하고 도시설계적 함의를 도출하는 것이 목적이다. 인천 남구 숭의동을 연구 대상지로선택하였으며, 정성적인 연구방법론을 통해 도시쇠퇴와 빈집 사이의 메커니즘을 이론적 틀로 정리하고, 빈집의 분포현황과 특성, 인과관계를 파악하였다. 숭의동에는 총 80개의 빈집이 4개의클러스터에 집중 분포되어 있었으며, 각 클러스터의 서로 다른 물리적 특성이 빈집 발생 양상의차이를 만들어내는 요인으로 작용하고 있었다. 폐쇄적 블록, 협소한 가로, 소규모 필지 등의 열악한 물리적 환경은 재정비촉진지구의 해제, 사회취약계층의 공간적 집중과 결합되어 빈집의 확산으로 연결되었다. 그리고 빈집 인근 공적영역의 유지관리 여부가 추가적인 쇠퇴진행 및 쇠퇴이미지 형성에 중요한 역할을 하고 있었다. 더불어 거주위치 및 거주특성에 따라 주민들이 빈집문제의 심각성을 인식하고 대응하는데 있어 차이가 존재함을 확인할 수 있었다.

We have designed and synthesized six phthalocyanine dyes and one benzoperylene dye for dye-based green Liquid Crystal Display (LCD) color filters. The solubility, spectral properties and thermal stability of the prepared six phthalocyanine dyes varied depending on their isomeric structures and core metals. They were dissolved in industrial solvent–binder composites and spin coated with and without yellow compensating benzoperylene dye into dye-based LCD color filters. The prepared color filters

Four novel asymmetric triphenylamine dyes configured with donor–donor–acceptor (D–D–A) and donor–donor–bridge–acceptor (D–D–π–A) structures were synthesized and applied to organic dye-sensitized solar cells. The terminal methoxy group in the donor part and the furane-bridge unit contributed to the wider absorption region and enhanced electron life time, resulting in a higher photocurrent density (Jsc), open-circuit voltage (Voc), and overall conversion efficiency (η). Among the synthesized dyes,