Effective nonmetal incorporation in black titania with enhanced solar energy utilization

Nonmetal-doped black titania is achieved in a core–shell structure by a two-step synthesis. The nonmetal dopants in amorphous TiO2−x shells decrease e–h recombination centers, and more than 6.6 at.% N further improves solar energy absorption from 65% up to 85%. The photocatalytic H2 generation of the N-doped black titania is 15.0 mmol h−1 g−1 under 100 mW cm−2 of full-sunlight and 200 μmol h−1 g−1 under 90 mW cm−2 of visible-light irradiation, superior to TiO2−x and reported titania photocatalysis.