title: Crystallinity-dependent substitutional nitrogen doping in ZnO and its improved visible light photocatalytic activity.
abstract: Increasing visible light absorption of wide-bandgap photocatalysts (for example, ZnO and TiO2) plays a pivotal role in improving their photocatalytic activity. In this work, we show that substitutional nitrogen doping can be realized in semi-crystalline zinc oxide (ZnO) nanoparticles but fails for highly crystalline ZnO by heating the ZnO at a temperature of 400°C in gaseous ammonia atmosphere. The results suggest that substitutional nitrogen for lattice oxygen is strongly dependent on the crystallinity of ZnO. The nitrogen doped ZnO obtained shows an improved visible light photocatalytic activity in the degradation of organic dyes due to its increased visible light absorption. The origin of the increased visible light absorption is theoretically attributed to the formed N 2p localized states in the bandgap.
authors.affiliation: Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Zongbao
authors.initials: Z
authors.lastname: Yu
authors.forename: Li-Chang
authors.initials: LC
authors.lastname: Yin
authors.forename: Yingpeng
authors.initials: Y
authors.lastname: Xie
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.forename: Xiuliang
authors.initials: X
authors.lastname: Ma
authors.forename: Hui-Ming
authors.initials: HM
authors.lastname: Cheng