tailieunhanh - Organic Light Emitting Diode Material Process and Devices Part 2

Tham khảo tài liệu 'organic light emitting diode material process and devices part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 16 Organic Light Emitting Diode - Material Process and Devices conductivity in the absence of conductive polymers. This high voltage was improved when the conductive host polymer 16 was added to the luminescent layer. However the maximum current efficiencies were not so different among devices H I and K L in spite of the different iridium unit content ratios in these metallopolymers 7a and 7b 7a 7b see Tables 1-3 . Although the total performances of these devices based on the Vc copolymer were still not satisfactory the energy transfer from the host polymer 16 to the metallopolymers occurred smoothly leading to decrease of luminescence at 435 nm from the host 16 in comparison with copolyMMA-based devices. entry Device Emitting Layer Metal Unit Content6 Vh V c max cd A V nm Host6 Guest Feed Ratio Host Guest wt 1 A 5 0 100 Ir 49 635 2 B 16 5 80 20 Ir 430 3 C 16 5 90 10 Ir 435 4 D 16 5 95 5 Ir 435 5 E 6 0 100 Pt 41 6 F 16 6 95 5 Pt 435 7 G 7a 0 100 Ir 625 8 H 16 7a 60 40 Ir 430 9 I 16 7a 80 20 Ir 430 10 J 7b 0 100 Ir 25 630 11 K 16 7b 60 40 Ir 10 430 12 L 16 7b 80 20 Ir 5 430 13 M 10 0 100 Ir 625 14 N 11 0 100 Pt 605 650 15 O 12 0 100 Ir 620 16 P 13 0 100 Pt 605 650 17 Q 16 14 90 10 Ir 10 625 18 R 16 14 95 5 Ir 615 19 S PVK 14 95 5 Ir 630 20 T 16 15 90 10 Pt 10 605 650 21 U 16 15 95 5 Pt 435 a Device structure ITO PEDOT PSS Emitting layer Ba Al Metal unit is MCl piq n Py- n 2 Ir n 1 Pt or the monomeric complex in the emitting layer. c Threshold voltage at 1 cd m2. d Maximum current efficiency. e The max values correspond to the highest intensity peak in the EL spectrum at maximum current efficiency. Table 5. EL properties of the devices .