화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.44, No.52, 28173-28183, 2019
A wide visible light active photocatalyst Mg5Ta4O15-xNy for water oxidation and reduction
More than 1.6 eV band gap reductions have been realized on Mg5Ta4O15 by nitrogen doping with its pseudobrookite structure maintained. The nitrogen doped Mg5Ta4O15, i.e. Mg5Ta4O15-xNy, shows broad absorption in the visible light region and promising photocatalytic activity for both water reduction and oxidation reactions under visible light illumination (lambda >= 400 nm). Apparent quantum efficiency as high as similar to 0.90% has been achieved at 420 +/- 20 nm on Mg5Ta4O15-xNy which is comparable to a number of active metal oxy-nitrides photocatalysts. Apart from visible light absorption, Nitrogen doping on Mg5Ta4O15 is also accompanied by improved surface hydrophilicity and a negative shift of flat band potential. This simple strategy for band gap engineering can be extended to other metal oxides which may open new playgrounds in the design and development of efficient visible light active photocatalysts. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.