Promotional effect of silver nanoparticle embedded Ga–Zr-codoped TiO2 as an alternative anode for efficient blue, green and red PHOLEDs

Abstract

Efficient blue, green and red phosphorescent OLEDs have been harvested from silver nanoparticles embedded at a glass:Ga–Zr-codoped TiO₂ interface. The embedded silver nanoparticles at the interface removed the non productive hole current and enhanced the efficiencies. The blue emitting device (456 nm) with emissive layer Ir(fni)₃ exhibits a maximum luminance (L) of 40 512 cd m⁻² (ITO – 37 623 cd m⁻²), current efficiency (η_c) of 41.3 cd A⁻¹ (ITO – 40.5 cd A⁻¹) and power efficiency (η_p) of 43.1 lm w⁻¹ (ITO – 39.8 lm w⁻¹) and external quantum efficiency (η_ex) of 19.4% (ITO – 6.9%). A newly fabricated green device based on emissive layer Ir(tfpdni)₂(pic) shows intensified emission at 514 nm, luminance of 46 435 cd m⁻² (ITO – 40 986 cd m⁻²), current efficiency of 49.7 cd A⁻¹ (ITO – 47.3 cd A⁻¹), power efficiency of 48.6 lm w⁻¹ (ITO – 41.4 lm w⁻¹) and external quantum efficiency of 17.5% (ITO – 14.9%). The red device (618 nm) with emissive layer Ir(bbt)₂(acac) shows luminance of 8936 cd m⁻² (ITO – 8043 cd m⁻²), current efficiency of 6.9 cd A⁻¹ (ITO – 4.6 cd A⁻¹), power efficiency of 5.7 lm w⁻¹ (ITO – 4.9 lm w⁻¹) and external quantum efficiency of 9.3% (ITO – 6.9%).