Buffer-modified C_(60)/pentacene as charge generation layer(CGL) is investigated to achieve effective performance of charge generation. Undoped green electroluminescent tandem organic light-emitting diodes(OLEDs) with...Buffer-modified C_(60)/pentacene as charge generation layer(CGL) is investigated to achieve effective performance of charge generation. Undoped green electroluminescent tandem organic light-emitting diodes(OLEDs) with multiple identical emissive units and using buffer-modified C_(60)/pentacene organic semiconductor heterojunction(OHJ) as CGL are demonstrated to exhibit better current density and brightness, compared with conventional single-unit devices. The current density and brightness both can be significantly improved with increasing the thickness of Al. However, excessive thickness of Al seriously decreases the transmittance of films and damages the interface. As a result, the maximum current efficiency of 1.43 cd·A^(-1) at 30 mA ·cm^(-2) can be achieved for tandem OLEDs with optimal thickness of Al. These results clearly demonstrate that Cs_2CO_3/Al is an effective buffer for C_(60)/pentacene-based tandem OLEDs.展开更多
基金supported by the National Nature Science Foundation of China(No.61604027)the Scientific and Technological Research Foundation of Chongqing Municipal Education Commission(Nos.KJ1400411 and KJ1600439),the Scientific and Technological Research Foundation of Chongqing Municipal Education Commission(No.KJ1500404)+1 种基金the Youth Natural Science Foundation of Chongqing University of Posts and Telecommunications(No.A2013-39)the Basic and Advanced Technology Research Project of Chongqing Municipality(No.cstc2016jcyA 1923)
文摘Buffer-modified C_(60)/pentacene as charge generation layer(CGL) is investigated to achieve effective performance of charge generation. Undoped green electroluminescent tandem organic light-emitting diodes(OLEDs) with multiple identical emissive units and using buffer-modified C_(60)/pentacene organic semiconductor heterojunction(OHJ) as CGL are demonstrated to exhibit better current density and brightness, compared with conventional single-unit devices. The current density and brightness both can be significantly improved with increasing the thickness of Al. However, excessive thickness of Al seriously decreases the transmittance of films and damages the interface. As a result, the maximum current efficiency of 1.43 cd·A^(-1) at 30 mA ·cm^(-2) can be achieved for tandem OLEDs with optimal thickness of Al. These results clearly demonstrate that Cs_2CO_3/Al is an effective buffer for C_(60)/pentacene-based tandem OLEDs.
