Water-Soluble Lacunary Polyoxometalates with Excellent Electron Mobilities and Hole Blocking Capabilities for High Efficiency Fluorescent and Phosphorescent Organic Light Emitting Diodes
Küçük Resim Yok
Tarih
2016
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
WILEY-V C H VERLAG GMBH
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
High performance solution-processed fluorescent and phosphorescent organic light emitting diodes (OLEDs) are achieved by water solution processing of lacunary polyoxometalates used as novel electron injection/transport materials with excellent electron mobilities and hole blocking capabilities. Green fluorescent OLEDs using poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadiazole)](F8BT) as the emissive layer and our polyoxometalates as electron transport/hole blocking layers give a luminous efficiency up to 6.7 mu m W-1 and a current efficiency up to 14.0 cd A(-1) which remained nearly stable for about 500 h of operation. In addition, blue phosphorescent OLEDs (PHOLEDs) using poly(9-vinylcarbazole) (PVK): 1,3-bis[2(4-tert-butylphenyl)-1,3,4-oxadiazo-5-yl] benzene (OXD-7) as a host and 10.0 wt% FIrpic as the blue dopant in the emissive layer and a polyoxometalate as electron transport material give 12.5 mu m W-1 and 30.0 cd A(-1) power and luminous efficiency, respectively, which are among the best performance values observed to date for all-solution processed blue PHOLEDs. The lacunary polyoxometalates exhibit unique properties such as low electron affinity and high ionization energy (of about 3.0 and 7.5 eV, respectively) which render them as efficient electron injection/hole blocking layers and, most importantly, exceptionally high electron mobility of up to 10(-2) cm(2) V-1 s(-1).
Açıklama
Anahtar Kelimeler
Kaynak
ADVANCED FUNCTIONAL MATERIALS
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
26
Sayı
16
