CHEN Wei-hua, WANG Hua, ZHAO Bo etc. High Efficient Phosphorescent Organic Light-emitting Diodes Based on Organic Semiconductor Heterojunctions of C<sub>60</sub> and CuPc as Anode Modified Layer[J]. Chinese Journal of Luminescence, 2017,38(12): 1636-1642
CHEN Wei-hua, WANG Hua, ZHAO Bo etc. High Efficient Phosphorescent Organic Light-emitting Diodes Based on Organic Semiconductor Heterojunctions of C<sub>60</sub> and CuPc as Anode Modified Layer[J]. Chinese Journal of Luminescence, 2017,38(12): 1636-1642 DOI: 10.3788/fgxb20173812.1636.
High Efficient Phosphorescent Organic Light-emitting Diodes Based on Organic Semiconductor Heterojunctions of C60 and CuPc as Anode Modified Layer
High efficient green phosphorescent organic light-emitting diodes (OLEDs) were fabricated based on semiconductor heterojunctions of C
60
and CuPc as the anode modified layer. Compared with the reference device based on MoO
3
as the anode modified layer
the maximum current efficiency and EQE for C
60
(5 nm)/CuPc(25 nm) planar heterojunction modified device are improved by 12% and 11%
reaching up to 60 cd/A and 16.8%
respectively; and the values for CuPc:C
60
(50%
30 nm) bulk heterojunction based device are increased by 26% and 27%
arriving at 67 cd/A and 19.3%
respectively. On one hand
the superior device efficiency based on heterojunction modified layer can be attributed to efficient dissociation and hole injection of accumulated charges generated in the heterojunction interfaces driven by the external electrical field. On the other hand
the higher efficiency is also attributed to the photovoltaic effect of heterojunction which can utilize the green photon to produce photon-generated carriers. Due to the more efficient charge accumulation and more proper carrier transport property
more balanced recombination of carriers and better photovoltaic effect
the bulk heterojunction modified device owns the higher efficiency comparing with the planar heterojunction modified device. The study demonstrates that the organic semiconductor heterojunction can become a kind of superior anode modified layer.
关键词
Keywords
references
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