➀ The study investigates the enhanced photocatalytic hydrogen production capabilities of nanoscale covalent organic frameworks (COFs). ➁ It highlights the importance of nanoscale dimensions and charge separation in achieving high hydrogen yields. ➂ The synthesized TFP-BpyD nano-COF demonstrates high photocatalytic activity with a mass-normalized hydrogen production rate of 392.0 mmol g⁻¹ h⁻¹.