Black and yellow anatase titania formed by (H,N)-doping: strong visible-light absorption and enhanced visible-light photocatalysis.

Black and yellow anatase TiO2 doped with hydrogen and nitrogen elements annealed under a N2/Ar/air atmosphere are produced. More interestingly, one kind of black TiO2 has excellent performance for degradation of methylene blue under visible-light irradiation but photodegradation of the other is quite limited.