A Graphitic-C₃N₄ "seaweed" Architecture for Enhanced Hydrogen Evolution

A seaweed-like graphitic-C₃N₄ (g-C₃N₄ "seaweed") architecture has been prepared by direct calcination of the freeze-drying-assembled, hydrothermally treated dicyandiamide fiber network. The seaweed network of mesoporous g-C₃N₄ nanofibers is favorable for light harvesting, charge separation and utilization of active sites, and has highly efficient photocatalytic behavior for water splitting. It exhibits a high hydrogen-evolution rate of 9900 μmol h^-1 g^-1 (thirty times higher than that of its g-C₃N₄ bulk counterpart), and a remarkable apparent quantum efficiency of 7.8 % at 420 nm, better than most of the g-C₃N₄ nanostructures reported. This work presents a very simple method for designing and developing high-performance catalysts for hydrogen evolution.