Controllable synthesis of hollow COFs for boosting photocatalytic hydrogen generation.

COF-LZU1 with a cubic hollow structure was fabricated through a hard template approach by using water solvable NaCl as a template. The precisely prepared COF-LZU1 hollow cube displays an enhanced H 2 evolution rate (651 μmol h -1 g -1 ), which is approximately 1.8 times greater than that of pristine COF-LZU1 (361 μmol h -1 g -1 ).