Fabrication of Ag2O/KNbO3 heterojunction with high visible-light photocatalytic activity

  • Xiaoxiao Lu
  • XiangDong Ma
  • Qiang LiEmail author
  • Kai Dai
  • Jinfeng Zhang
  • Min Zhang
  • Chaopeng Cui
  • Guangping Zhu
  • Changhao LiangEmail author
Research Paper


In the present work, a series of Ag2O/KNbO3 composite photocatalysts are prepared for the first time through an in situ growth method. The as-obtained samples are well characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, UV-vis absorption spectroscopy, and X-ray photoelectron spectroscopy. The photocatalytic properties of the samples are assessed by decomposition of rhodamine B (RhB) under visible-light excitation. The results demonstrate Ag2O/KNbO3 illustrated superior photocatalytic activity. The rate constant of RhB degradation over the optimal sample (Ag2O/KNbO3-6:1) exceeded 2.78 and 65 times higher than that of pure Ag2O and KNbO3, respectively. The improved photocatalytic activity could be due to the heterostructure of the catalyst, which enhance the visible light absorption capacity and the separation efficiency of photogenerated carriers. The quenching experiments of varied scavengers illustrated that •O2 and h+ were the primary active species in the decoloration of RhB.


Ag2KNbO3 Heterostructure Photocatalyst 


Funding information

We gratefully acknowledge the financial support of the Natural Science Foundation of Anhui Province (1908085QF293 and 1908085QA36), the Natural Science Foundation of China (51572103 and 51973078), and the Foundation of Educational Commission of Anhui Province (KJ2018A0394, KJ2018A0393, and KJ2016SD53).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  • Xiaoxiao Lu
    • 1
  • XiangDong Ma
    • 1
  • Qiang Li
    • 1
    Email author
  • Kai Dai
    • 1
  • Jinfeng Zhang
    • 1
  • Min Zhang
    • 1
  • Chaopeng Cui
    • 1
  • Guangping Zhu
    • 1
  • Changhao Liang
    • 2
    Email author
  1. 1.College of Physics and Electronic InformationHuaibei Normal UniversityHuaibeiPeople’s Republic of China
  2. 2.Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical ScienceChinese Academy of SciencesHefeiPeople’s Republic of China

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