title: High efficiency new hole injection materials for organic light emitting diodes based on dimeric phenothiazine and phenoxazine moiety derivatives.
abstract: New hole injection materials for organic light emitting diodes (OLEDs) based on phenothiazine and phenoxazine were synthesized, and the electro-optical properties of synthesized materials were examined by through UV-visible (UV-vis), photoluminescence (PL) spectrum and cyclic voltammetry (CV). 1-BPNA-t-BPBP and 1-BPNA-t-BPBPOX showed T(g) of 127 and 200 degrees C, which are higher than that (110 degrees C) of 2-TNATA, a commercial hole injection layer (HIL) material. The highest occupied molecular orbital (HOMO) level of the synthesized materials of 1-BPNA-t-BPBP and 1-BPNA-t-BPBPOX were 4.97 and 4.91 eV, indicating values well-matched between HOMO (4.8 eV) of ITO and HOMO (5.4 eV) of NPB, hole transporting layer (HTL) material. As a result of using the synthesized materials in OLED device as HIL, 1-BPNA-t-BPBPOX of 2.43 Im/W was higher than 2-TNATA of 1.98 Im/W and 1-BPNA-t-BPBP of 1.39 Im/W in power efficiency. These results indicated that 1-BPNA-t-BPBPOX shows higher excellent power efficiency which is about 18% improved over 2-TNATA a commercial HIL material.
authors.affiliation: Department of Chemistry, The Catholic University of Korea, Bucheon, 420-743, Korea.
authors.forename: Youngil
authors.initials: Y
authors.lastname: Park
authors.forename: Beomjin
authors.initials: B
authors.lastname: Kim
authors.forename: Changjun
authors.initials: C
authors.lastname: Lee
authors.forename: Jaehyun
authors.initials: J
authors.lastname: Lee
authors.forename: Ji-Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Jongwook
authors.initials: J
authors.lastname: Park