Fig. 1. Schematic structure of the WOLED with Ag@SiO₂ NCs doped in ETL.

Fig. 2. TEM images of (a) Ag NCs and (b) Ag@SiO₂ NCs; (c) Absorption spectra of TPBi and TPBi:Ag@SiO₂ NCs, and PL spectra of FIrpic and PO-01; (d) SEM image of the surface of ETL doped with Ag@SiO₂ NCs.

Fig. 3. (a) Luminance-voltage, (b) current density-voltage, (c) efficiency-luminance properties and (d) normalized electroluminescent spectra of the WOLEDs with 1%, 1.5%, 2% Ag@SiO₂ NCs and the control device. The inset of Fig. (d) is the normalized electroluminescent spectra of the WOLED with 1.5% Ag@SiO₂ NCs at different luminance.

Fig. 4. (a) PL spectra and (b) normalized PL spectra of the samples of ITO/PEDOT:PSS (45 nm)/EML (50 nm)/ETL (45 nm) doped with 1%, 1.5% and 2% Ag@SiO₂ NCs and the control sample without NCs.

Fig. 5. Current density-voltage property of the electron-only devices.

Fig. 6. (a) Current density-voltage, (b) luminance-voltage and (c) current efficiency-luminance properties of the WOLEDs with Ag@SiO₂ NCs doped in different layers and the control device without Ag@SiO₂ NCs.