Polarized dislocation covalent organic frameworks ignite hot electrons to propel photocatalytic hydrogen generation

Covalent organic frameworks are promising photocatalysts for H₂ generation; however, their efficiency is limited by energy dissipation arising from hot electron loss and carrier recombination. In this work, we introduce interlayer dislocation and polarization in covalent organic frameworks to extend hot electron lifetime to 37.1 ± 2.0 ps, activating a photocatalytic H₂ generation rate of 429.4 ± 3.7 mmol g^-1 h^-1 and apparent quantum yield of 85 ± 1% at 420 nm. Ultrafast spectroscopy and theoretical calculation elucidate the underlying mechanisms of hot electron production: interlayer dislocations induce energy-band anti-crossing at the K point in the Brillouin zone, suppressing acoustic-phonon scattering to contribute 8.4 times extension of both hot and cooled electrons; polarization effects reduce exciton dissociation and carrier recombination, further increasing carrier and optical-phonon concentration to achieve hot-phonon bottleneck and 180 times of hot electron duration. This study validates hot-electron-enhanced photocatalytic hydrogen generation and offers a general strategy for manipulating hot electrons in two-dimensional photocatalysts.