TY - JOUR T1 - Improved performance of flexible perovskite light-emitting diodes with modified PEDOT:PSS hole transport layer AU - Kim, Haesook AU - Ra, Ha Na AU - Kim, Ji Sun AU - Paek, Sang-Hyon AU - Park, Jongwook AU - Kim, Young Chul JO - Journal of Industrial and Engineering Chemistry VL - 90 SP - 117 EP - 121 PY - 2020 DA - 2020/10/25/ SN - 1226-086X DO - https://doi.org/10.1016/j.jiec.2020.07.003 UR - https://www.sciencedirect.com/science/article/pii/S1226086X20302914 KW - Perovskite light-emitting diodes KW - Modified PEDOT:PSS KW - Flexible substrates AB - We demonstrated the improved device performance of flexible perovskite light-emitting diodes (PeLEDs) on indium-tin oxide coated poly(ethylene terephthalate) (ITO/PET) substrates by using modified poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) as a hole transport layer (HTL). Solvent modification and dopant modification of the PEDOT:PSS solution were carried out by adding isopropyl alcohol (IPA) and poly(sodium 4-styrenesulfonate) (PSS-Na), respectively, to the pristine solution. Devices with the modified HTLs, PEDOT:PSS+IPA and PEDOT:PSS+PSS-Na, exhibited a significant enhancement in both luminance and efficiency. The work function of HTL was improved to reduce the energy barrier against the perovskite layer and facilitate hole transport. The perovskite films deposited on the modified PEDOT:PSS layers showed a uniformly covered surface morphology without any defects, resulting in an increased PL intensity. In particular, the perovskite film coated on the dopant modified HTL showed a better crystallinity and reduced luminescence quenching. The PeLED device with the PEDOT:PSS+PSS-Na HTL exhibited a maximum luminance of 3900cd/m2, a maximum current efficiency of 25.1cd/A, and a maximum external quantum efficiency of 5.9%. ER -