Fig. 2: TTA-UC device performance.

a Photographs of the PYIT1:PBQx-TCl:rubrene film alone (i), and with an additional neat rubrene film (ii) or PYIT1:PBQx-TCl film (iii) between the laser and the PYIT1:PBQx-TCl:rubrene film, under 808-nm laser illuminations. b UC emissions from the PYIT1:PBQx-TCl:rubrene and PYIT1:PBQx-TCl:rubrene:DBP films under 808-nm laser illuminations. c The ΦUC of the PYIT1:PBQx-TCl:rubrene and PYIT1:PBQx-TCl:rubrene:DBP UC devices as a function of power density. d The UC emission intensities of the PYIT1:PBQx-TCl:rubrene and PYIT1:PBQx-TCl:rubrene:DBP UC devices as a function of power density. S represents slope.