Preparation of the CaAl2O4:Eu2+, Nd3+/TiO2 composite by peroxo titanium complex solution and its photodegradation of methylene blue

Qiushi Xu, Shielah Mavengere, Jung Sik Kim

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

CaAl2O4:Eu2+, Nd3+ phosphor was synthesized by a solid-state method at 1400 °C. The CaAl2O4:Eu2+, Nd3+ phosphor particles were coated by sol–gel dip coating method with a peroxo treated titanium hydroxide complex solution. The effect of peroxo treatment time and calcination temperatures was investigated in comparison with conventional TiO2-sol coated nanocomposites. Characterization of the CaAl2O4:Eu2+, Nd3+/TiO2 nanocomposites was conducted by X-ray diffraction, scanning electron microscopy, UV–Vis absorption spectra, and energy dispersive spectroscopy. The photocatalytic reactivity was evaluated by degradation of methylene blue aqueous solution under ultra-violet and visible light irradiations. CaAl2O4:Eu2+, Nd3+/TiO2 composite coated with peroxo titanium complex solution for 80 s showed the fastest photocatalytic reactivity under ultra violet and visible light illumination. Peroxo treatment for a long soaking time of 300 s effected etching of the phosphor surface and formation of CaTiO3 phases. With prolongation of the time of soaking the phosphor in the peroxo titanium complex solution to 300 s, the photocatalytic reactivity of the CaAl2O4:Eu2+, Nd3+/TiO2 composite decreased. In addition, composites displayed excellent photocatalytic under visible light irradiation, compared with pure TiO2. The acidity of the peroxo treatment, soaking time, and heat treatment conditions are important parameters for synthesizing photoactive nanocomposites for pollution control application. Graphic abstract: CaAl2O4:Eu2+, Nd3+ was coated with peroxo treated TiO2-sol under different coating times. The peroxo treatment imparted acidic pH while longer soaking times resulted in etching of the phosphor surface. A wavy micro-ridge microstructure with dispersed clusters of TiO2 was dominant in the 300 s coated samples. The samples without peroxo treated (CTB) and 80 s coated samples were densely coated with TiO2 nanoparticles. The CaAl2O4:Eu2+, Nd3+/TiO2 samples coated in peroxo titania sol exhibited the most superior photocatalytic degradation of methylene blue aqueous solution under ultra-violet and visible light irradiations. [Figure not available: see fulltext.].

Original languageEnglish
Pages (from-to)473-484
Number of pages12
JournalReaction Kinetics, Mechanisms and Catalysis
Volume134
Issue number1
DOIs
StatePublished - Oct 2021

Keywords

  • CaTiO
  • Peroxo titanium complex
  • Phosphor
  • Photocatalyst
  • Titanium dioxide

Fingerprint

Dive into the research topics of 'Preparation of the CaAl2O4:Eu2+, Nd3+/TiO2 composite by peroxo titanium complex solution and its photodegradation of methylene blue'. Together they form a unique fingerprint.

Cite this