TY - JOUR
T1 - High-performance near-infrared (NIR) polymer light-emitting diodes (PLEDs) based on bipolar Ir(iii)-complex-grafted polymers
AU - Li, Wentao
AU - Wang, Baowen
AU - Miao, Tiezheng
AU - Liu, Jiaxiang
AU - Fu, Guorui
AU - Lü, Xingqiang
AU - Feng, Weixu
AU - Wong, Wai Yeung
N1 - Funding Information:
This work was funded by the National Natural Science Foundation (21373160, 21173165), the State Key Laboratory of Structure Chemistry (20190026), the Guangdong Basic and Applied Basic Research Foundation (2019A1515110527), the Wisteria Scientific Research Cooperation Special Project of Northwest University, the Hong Kong Research Grants Council (PolyU153058/19P), the Hong Kong Polytechnic University (1-ZE1C, YW4T) and the Endowed Professorship in Energy from Ms Clarea Au (847S) in China.
Publisher Copyright:
© The Royal Society of Chemistry.
PY - 2021/1/7
Y1 - 2021/1/7
N2 - Despite the cost-effective and large-area scalable advantages of NIR-PLEDs based on iridium(iii)-complex-doped polymers, the intrinsic phase-separation issue leading to inferior device performance is difficult to address. In this study, taking the vinyl-functionalized [Ir(iqbt)2(vb-ppy)] (Hqibt = 1-(benzo[b]-thiophen-2-yl)-isoquinoline; vb-Hppy = 2-(4′-vinylbiphenyl-4-yl)pyridine) as the polymerized complex monomer, two series of Ir(iii)-complex-grafted polymers Poly(NVK-co-[Ir(iqbt)2(vb-ppy)]) and Poly((vinyl-PBD)-co-NVK-co-[Ir(iqbt)2(vb-ppy)]) (NVK = N-vinyl-carbazole; vinyl-PBD = 2-(4-(tert-butyl)phenyl)-5-(4′-vinyl-[1,1′-biphenyl]-4-yl)-2,5-dihydro-1,3,4-oxadiazole) are obtained, respectively. Moreover, by using the bipolar Ir(iii)-complex-grafted polymer further doped or grafted with an electron-transport unit as the emitting layer (EML), reliable NIR-PLEDs are realized. In particular based on the concurrent covalent-linkages of both the Ir(iii)-complex and the vinyl-PBD towards the carrier-balanced NIR-PLED-III, the achievement of an almost negligible (<5%) efficiency roll-off does not sacrifice the attractive efficiency (ηmaxEQE = 3.6%). This finding makes bipolar Ir(iii)-complex-grafted polymers a good platform to achieve high-performance NIR-PLEDs. This journal is
AB - Despite the cost-effective and large-area scalable advantages of NIR-PLEDs based on iridium(iii)-complex-doped polymers, the intrinsic phase-separation issue leading to inferior device performance is difficult to address. In this study, taking the vinyl-functionalized [Ir(iqbt)2(vb-ppy)] (Hqibt = 1-(benzo[b]-thiophen-2-yl)-isoquinoline; vb-Hppy = 2-(4′-vinylbiphenyl-4-yl)pyridine) as the polymerized complex monomer, two series of Ir(iii)-complex-grafted polymers Poly(NVK-co-[Ir(iqbt)2(vb-ppy)]) and Poly((vinyl-PBD)-co-NVK-co-[Ir(iqbt)2(vb-ppy)]) (NVK = N-vinyl-carbazole; vinyl-PBD = 2-(4-(tert-butyl)phenyl)-5-(4′-vinyl-[1,1′-biphenyl]-4-yl)-2,5-dihydro-1,3,4-oxadiazole) are obtained, respectively. Moreover, by using the bipolar Ir(iii)-complex-grafted polymer further doped or grafted with an electron-transport unit as the emitting layer (EML), reliable NIR-PLEDs are realized. In particular based on the concurrent covalent-linkages of both the Ir(iii)-complex and the vinyl-PBD towards the carrier-balanced NIR-PLED-III, the achievement of an almost negligible (<5%) efficiency roll-off does not sacrifice the attractive efficiency (ηmaxEQE = 3.6%). This finding makes bipolar Ir(iii)-complex-grafted polymers a good platform to achieve high-performance NIR-PLEDs. This journal is
UR - http://www.scopus.com/inward/record.url?scp=85099127904&partnerID=8YFLogxK
U2 - 10.1039/d0tc04377j
DO - 10.1039/d0tc04377j
M3 - Journal article
AN - SCOPUS:85099127904
SN - 2050-7534
VL - 9
SP - 173
EP - 180
JO - Journal of Materials Chemistry C
JF - Journal of Materials Chemistry C
IS - 1
ER -