This work synthesized three new compounds, conducted systematic structural characterization, photophysical, electrochemical, and charge mobility tests, and preliminarily demonstrated their performance in OLED devices. I recommend acceptance after revision.

1. The author claims the performance is "one of the best blue OLEDs in pillar-shaped materials," but lacks sufficient data support.
2. The author used SCLC method to measure electron mobility (~10-5 cm2/Vs), but failed to extract hole mobility, making it impossible to evaluate charge balance in EL devices.
3. Methyl replaces C4, C8, and C12 long chains in DFT calculations. For columnar stacking, van der Waals interactions and space filling of alkyl chains are crucial. The HOMO/LUMO distribution calculated using methyl groups (showing asymmetry) may not reflect the electronic structure of real molecules (especially 5b/5c), as the conformational entropy and stacking of long chains can alter the twist angle of the conjugated core.