Fig. 2. (a) Calculated excited states energy and NTO distributions for BOC-PC and BOC-PSi; (b) the plausible mechanism of harvesting triplet states for BOC-PC (top) and BOC-PSi (bottom); (c) EQE as a function of the current density (J) of BOC-PC-based device I, and BOC-PSi-based device II (inset: EL spectra of devices I–II at J of 10 mA cm⁻²); (d) current density–voltage–luminance (J–V–L) profiles of devices I–II; (e) comparison of EQE_max for the reported deep-blue OLED with CIE_y of 0.03–0.06.