Formation of surface defects by thermal shock method for the improved photocatalytic activity of ZnO nanoparticles

Tien Khoa Le, The Luan Nguyen, Chau Ngoc Hoang, Dieu Khanh An Nguyen, Torben Lund, Huu Khanh Hung Nguyen, Thi Kieu Xuan Huynh*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Surface-modified ZnO photocatalysts with enhanced UVA-light-driven and visible-light-driven activities were synthesized by the thermal shock method with Cu(NO3)2 at different thermal shock temperatures (300–600°C). The influences of thermal shock temperatures on the crystal structure, morphology, surface functional groups and surface composition of modified catalysts were investigated by XRD, TEM, Raman and XPS spectra, respectively. Their photocatalytic activity was evaluated via the degradation of methylene blue under both UVA and visible light irradiation. According to the results, by combining the thermal shock method and an agent with low thermal stability such as Cu(NO3)2, we did not modify the crystal structure, phase composition nor the morphology of ZnO nanoparticles, but successfully modified the surface of ZnO nanoparticles with the migration of zinc ions, leading to the creation of new environments of Zn2+ and O2 – ions as well as the formation of surface zinc vacancies. These evolutions were found to be able to enhance the photocatalytic performance in the UVA light region and also in the visible light region.

Original languageEnglish
JournalJournal of Asian Ceramic Societies
Volume8
Issue number1
Pages (from-to)193-202
Number of pages10
ISSN2187-0764
DOIs
Publication statusPublished - 2 Jan 2020

Bibliographical note

Funding Information:
This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number [104.03-2016.43].

Keywords

  • photocatalysis
  • surface modification
  • surface zinc vacancies
  • thermal shock
  • ZnO

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